text:
Virgin Galactic SpaceShip
2 pilots
SpaceshipOne
High-speed rocket-powered aircraft
Maiden Flight
Retired from Service
Loaded Weight
Approximately 1,100ft³
Altitude at Release from WhiteKnight Aircraft
Maximum Altitude at Apogee
Mach 3 (nearly 2,500mph)
Single hybrid rocket using solid fuel and liquid oxidiser
Lightweight composite material construction with feathering wings
Service Ceiling
112,000m
Rate of Climb
416.6m/s
SpaceshipTwo
Unveiled to Public
Owner and Operator
Designer and Manufacturer
Scaled Composites
SpaceShipOne gliding into Mohave Airport after becoming the first privately-funded manned spacecraft to leave the earth's atmosphere.
In October 2004, SpaceShipOne became the first privately-funded manned spacecraft to exceed an altitude of 328,000ft twice in 14 days, thereby winning the $10m Ansari X-Prize.
SpaceShipOne is the first of a family of commercial suborbital and orbital spacecraft that will be owned and operated by the Virgin Galactic spaceline company.
Sunrise over the Mohave desert as SpaceShipOne glides in to land.
The WhiteKnight carrier aircraft carries the SpaceShip vehicles to an altitude of 50,000ft for air launch.
SpaceShipTwo will provide six passengers per flight with the experience of leaving earth's atmosphere.
Possible design of the future Spaceport.
From take-off to an altitude of 50,000ft, the spacecraft is attached to the mothership, the WhiteKnight carrier aircraft.
The SpaceShip passengers will experience zero gravity weightlessness for about five minutes.
The Spaceship Company will develop the SpaceShipTwo suborbital space vehicle, the future orbital space vehicles and the WhiteKnight Two carrier aircraft.
Passengers will be able to carry out physical manoeuvres and exercises in zero gravity and also view the earth and space during the flight.
SpaceShipTwo attached to its mothership, White Knight Two, inside a hangar in Mojave, Caalifornia, US. Image courtesy of Virgin Galactic.
The Virgin Galactic SpaceShip is a family of commercial suborbital and orbital spacecraft that will be owned and operated by the Virgin Galactic spaceline company. The spaceships will allow the first suborbital space travel for private astronauts. On 7 December 2009, Virgin Galatic unveiled the first of its SpaceshipTwo craft at the Mojave Air and Space Port in California.
The remaining spaceships are under construction and are a larger and enhanced derivative of the SpaceShipOne space vehicles that were designed and built by the company Scaled Composites. The family of spaceships will be designed and built by The Spaceship Company, which was formed in 2005 by Scaled Composites and the Virgin Group.
The Spaceship Company will licence the spacecraft technologies under an agreement with Scaled Composites and will carry out the development of the operational systems, including the SpaceShipTwo suborbital space vehicle, the future orbital space vehicles and the carrier aircraft, the WhiteKnight Two aircraft (WK2). The Spaceship Company will also carry out the marketing of the space vehicles and the carrier aircraft to spaceflight operators.
"The Virgin Galactic spaceships will allow the first suborbital space travel for private astronauts."
The spaceline company Virgin Galactic has ordered the first five SpaceShipTwo spacecraft and the first two WhiteKnight Two carrier aircraft.
The first three space ships have been named VSS Enterprise, VSS Voyager, VSS Columbia.
The VSS Enterprise, designed and developed by Burt Rutan and attached to the Mojave Air and Spaceport aircraft carrier, performed a two-hour-54-minute flight in March 2010. It accommodates six passengers and two pilots. The test flight programme will continue through 2010 and 2011.
On 21 June 2004, SpaceShipOne made history by becoming the first privately-funded manned spacecraft to leave the earth's atmosphere, reaching an altitude of 328,491ft (62 miles or 100km). On 4 October 2004, SpaceShipOne became the first privately funded manned spacecraft to exceed an altitude of 328,000ft twice within 14 days, thereby winning the $10m Ansari X-Prize. The spacecraft reached an altitude of 367,442ft (69.6 miles or 112km). Around 600 people are currently employed on the project, a figure that will increase to 1,100 during the peak time of construction.
The spacecraft
SpaceShipOne is the first space vehicle of this series and was designed and built by Space Composite. Three SpaceShipOne vehicles were built at the Scaled Composites aerospace facilities at Mojave Air and Spaceport near Mojave, Southern California and near the USAF Edwards Air Force Base.
"The Spaceship Company will licence the spacecraft technologies under an agreement with Scaled Composites."
SpaceShipTwo is the family of space vehicles, derived from SpaceShipOne technologies, built by the SpaceShip Company and the first five SpaceShipTwo vehicles will be owned and operated by Virgin Galactic for suborbital flight. The first of the SpaceShipTwo aircraft for commercial flight, i.e. the maiden Virgin Galactic craft, is named 'VSS Enterprise' or 'Virgin SpaceShip Enterprise'.
SpaceShipThree is a proposed family of air vehicles for orbital flight.
The WhiteKnight carrier aircraft carry the SpaceShip vehicles to an altitude of 50,000ft and air-launches the SpaceShip vehicles.
WhiteKnight
The WhiteKnight Two carrier aircraft is flown by two pilots and is approximately of similar size to a Boeing 737 with an estimated rough order-of-magnitude take-off weight of 65,000kg.
White Knight Two (WK2) was rolled out in July 2008 and performed a successful maiden flight on 21 December 2008. The aircraft flew at an altitude of 16,000ft (4,879m) after an hour from take-off. It is powered by four Pratt & Whitney PW308A turbofan jet engines. The WK2 can support four daily space flights with 24-hour operation and is equipped with state-of-art avionics.
The SS2 will be carried by White Knight Two to 50,000ft (16km) before the spaceship is dropped and the rocket motor is fired to launch the craft into space from that altitude.
SpaceShipTwo
SpaceShipTwo has been designed avoiding complexity, with a minimum number of moving parts but with multiple levels of redundancy in all the key systems in order to provide an extremely safe and robust system at all stages of flight. Commercial operations are scheduled to begin upon completion of a full test programme.
The construction of SS2 began in 2007. The first phase of rocket motor test flight was completed in May 2009 and SpaceShipTwo was first unvelied to public on 7 December 2009. Commercial flights are expected to begin in 2012, with the Virgin SpaceShip Enterprise, the maiden Virgin Galactic SpaceShipTwo aircraft for commercial flight.
"The WhiteKnight carrier aircraft carry the SpaceShip vehicles to an altitude of 50,000ft."
The cabin is about the size of a Gulfstream G550 cabin, approximately 1,100ft³, and accommodates two pilots and six passengers.
The spacecraft is equipped with distinctive feathering wings. The wings are folded up in space, providing a feather or shuttlecock effect with extremely high drag for re-entry. This mechanism allows deceleration to occur at a significantly higher altitude than in previous space flight re-entries.
In the past, one of the greatest risks was the re-entry phase into the earth's atmosphere and the feathering design greatly reduces that risk.
When the spacecraft is in contact with the earth's atmosphere the feathered wings stabilise the spaceship in the correct attitude without pilot input, so the feathering wing design aligns the spaceship automatically, giving the pilot a less-critical flight-control task at re-entry.
SpaceShipTwo is of a lightweight composite material construction rather than of metal construction as in the space shuttle design and also does not feature a thermal protection system. The feathering wings provide high altitude rather than lower altitude deceleration in the atmosphere, so the thermal protection system installed on conventional designs is unnecessary.
SpaceShipTwo is air-launched from a carrier aircraft rather than the ground, which brings advantages in greater safety and reduced environmental impact.
The vehicle is powered by a single hybrid rocket using solid fuel and liquid oxidiser, rather than separate solid and liquid rocket boosters and engines.
Space flights are planned to initially operate from the Mojave Spaceport in Southern California. Mojave Spaceport is the first commercial spaceport to be licensed by the Federal Aviation Administration, in 2004. Scaled Composites is located at Mojave Spaceport.
"SpaceShipTwo has been designed avoiding complexity, with minimum moving parts."
Spaceport America, near Upham in New Mexico, is the world's first built-for-purpose commercial spaceport. The contract for the construction of the 110,152ft² hangar and terminal facility was awarded to New Mexico contractor by the New Mexico Spaceport Authority (NMSA) on 30 November 2009.
The construction work on a 10,000ft (3,048m) long runway which is currently under progress is scheduled for completion in mid 2010 with terminal hangar facility expected to be complete in early 2011.
The Spaceport was designed by Foster + Partners (based in London, UK), with URS Corporation (San Francisco, California), SMPC Architects (Albuquerque, New Mexico), PHA Consult (London, UK), Balis and Company (Philadelphia, PA) and Exploration-Synthesis Partners.
The hangar and terminal is a low-lying construction that uses natural earth as a berm. It utilises passive energy for heating and cooling and photovoltaic panels for electricity and water recycling. Design features include a rolling concrete shell which acts as a roof with large windows opening to a view of the runway and spacecraft.
The final design of Spaceport America, which uses a combination of geo-thermal, solar and wind power to create a lower carbon footprint, were displayed in January 2008.
Virgin Galactic is establishing its headquarters and mission control centre at Spaceport America. Future Virgin Galactic flights will be flown from Spaceport America.
The company is also looking at other potential spaceport locations around the world for future operations. Virgin Galactic signed an agreement with Spaceport Sweden in January 2006 to carry out studies leading to an operational agreement that this would be the first spaceport outside USA for Virgin Galactic flight campaigns. The studies include the feasibility of flights from Sweden into the Aurora Borealis (Northern Lights). The initial feasibility studies were completed by January 2008.
Spaceport America broke ground in New Mexico on 19 June 2009. The facility will allow private astronauts to take tourist suborbital spaceflights and bring down the cost of commercial space travel.
The spaceport features a cost-effective and energy-efficient green design. The terminal hangar was built according to the US Green Building Council's LEED rating system.
While, the Mexican Government invested about $200m on its development, Virgin Galactic, a spaceline company poured $300m into a new space launch system to be operated from the spaceport.
The spaceship vehicles and the passenger procedures are being designed to allow almost anyone to experience genuine space flight without the need for special expertise or to carry out exhaustive and time-consuming training.
Before space flight, the passengers complete three days of pre-flight preparation and training. This includes training inside a duplicated SpaceCraftTwo cabin installed in the WhiteKnight carrier aircraft.
"Space flights are planned to operate from the Mojave Spaceport in Southern California."
The passengers learn how to be comfortable in zero gravity and macrogravity. The spacecraft pilots and crew experience up to 4g in ascent and up to 7g in descent, but at a very much slower rate of change than in the +6g to –3g experienced by pilots in fighter aircraft manoeuvres.
The spacecraft seats are inclined so the g-forces act in the direction from the chest towards the back of the body rather than downwards from the head directly down the body as experienced by fighter aircraft pilots.
In zero gravity it is expected that some passengers may wish to remain in their seats throughout the duration of the spaceflight. Many passengers will plan to carry out physical manoeuvres and exercises in zero gravity and also spend time viewing the earth and space during the flight. The training sessions will help the passengers plan and prepare to make the best use of their time in spaceflight.
Pre-flight medical checks ensure that passengers can fly safely. Very few would be prevented from flying, for example through heart conditions or brittle bone conditions.
The space flight
The spaceflights will initially take place once a week and will then progress to one and potentially two flights a day. Six pilots are deployed on each flight, two spacecraft pilots in the SpaceShipTwo with the six passengers; two pilots in the WhiteKnight 2 carrier aircraft; and two pilots in the ground-based mission control at the spaceport.
From take-off at the spaceport to an altitude of 50,000ft, the spacecraft is attached to the mothership, the WhiteKnight carrier aircraft. At 50,000ft the countdown to release is started and the spacecraft is unlocked from the WhiteKnight aircraft. The hybrid rocket motor on the spacecraft is ignited.
"The SpaceShipTwo test flights are expected to complete in 2009 with commercial flights beginning in 2010."
The passengers then experience macrogravity to 4G and hear the roar of the rocket motor as the spacecraft accelerates to Mach 3, nearly 2,500mph, in a few seconds. The spacecraft climbs from 50,000ft to 360,000ft in a near vertical climb in about 90 seconds.
The passengers experience the silence of space as rocket motor switches off. As the spacecraft passes through the edge of the atmosphere the passengers see the colour change of the sky from cobalt blue, to mauve, to indigo and then to black.
A 'Welcome to Space' announcement is made in the cabin and the passengers can unbuckle their seatbelts to fully experience zero gravity.
The passengers experience weightlessness for about five minutes. The view of the blue Earth curving into black space and the narrow band of Earth's blue atmosphere is seen through the spacecraft window.
Shortly before the spaceship reaches its maximum altitude (apogee) at about 360,000ft, the wings are feathered or folded in preparation for re-entry into the Earth's atmosphere.
The pilots ask the passengers to return to the seats and the sensation of weightlessness diminishes as gravity starts to return and the spaceship is drawn by gravitational pull. The spacecraft decelerates producing strong g-forces. The passengers experience the high g-force, up to 7g, in a lying position.
The feathered wings of the spacecraft produce a powerful drag against the increasing thickness of the atmosphere. At 60,000ft, the pilot announces that the spacecraft is being re-feathered and the wings are reconfigured to their original position. The g-forces diminish quickly as the spacecraft commences its homeward unpowered glide back to the spaceport. The total flight time from take-off to landing is about two and a half hours.


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While discussing a very luxurious item some time ago, a friend said I would need "surplus money" in order to buy it. At the time, it occurred to me that this was not only a very unusual phrase, but that there were also a few people around who would never acquire this bounteous state.
I was reminded of this recently while riding the little train up the side of a hill on the west side of Los Angeles to visit the Getty Center. With just an $8 parking fee, the rest of the visit is free once you set foot on the train. The center above is perhaps the greatest example of surplus money you can find, with a collection of such variety and opulence as to make assessment of its total wealth overwhelming.
J. Paul Getty was, at one time, one of the richest men in the world. He died in 1976, some 20 years after beginning his foundation by opening his Santa Monica home to visitors.
Not known for his personal generosity – he installed a pay phone at his English country house to accommodate visitors needing to keep in touch with those afar – he nonetheless allowed the public to share his early interest in three main areas: ancient antiquities from Rome and Greece, 18th century French furniture and European paintings.
He later built a Roman-style villa near Pacific Palisades and streams of visitors poured in on weekends. The number of visitors was regulated only by the available parking places; you had to call ahead to reserve a spot.
With this limitation in mind, the Getty Center was designed to allow plenty of parking at the bottom and access via a train to the exhibition pavilions at the top.
Throughout the 1990s, motorists working their way up and down the infamous 405 Freeway would see the construction of this pale yellow structure above the hills and wonder at its eventual use.
Once the center opened, the rush to see it was so great that, once again, visitors had to call ahead and book a parking place. Eventually, the flow of visitors settled and now it's possible to go along casually and get in.
I took my 12 year-old grandson with me. He had been once before with his school, but I hoped this time it would be a less constricted visit. I suggested that he not try to look at everything there, but to find things that really appealed to him. Also to select one item that he really liked; and jokingly I said I would buy it for him.
We toured three areas – the early carvings from Europe of mainly religious objects; even earlier antiquities from the Cleveland Museum's traveling show, and then some European paintings.
I thought my grandson might be attracted to some gold ornaments from the Middle Ages, but it was not to be. We looked at some Rembrandt paintings and he found them to be somewhat dark.
Finally, we came to the French Impressionists exhibition, and we took some time to look at Monet, Manet, Van Gogh and Pissarro.
Of all the exhibits, my grandson said he really liked one painting by Monet called "Sunrise." He also wanted to know how much it would cost.
Looking around the room at some dozen or so priceless works of art, and then calculating four pavilions with two floors each, plus the stuff in storage and the newly reopened original villa, I came to truly realize the meaning of the term surplus money: But perhaps more importantly, how it has, in this case, been used to benefit us all.


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text:
New Document Consolidates Russia's Nuclear Policy in One Place
Olga Oliker
Rejoice nuclear strategy nerds! On June 2, the Russian Federation published a brand new document titled "Foundations of State Policy of the Russian Federation in the Field of Nuclear Deterrence." In this six-page document, Russia has laid out its official position on nuclear deterrence.
This is the first time we've seen such a thing from Moscow. Any prior versions were classified. Thus, for decades, those of us who wanted to write about Russian approaches to nuclear weapons had to piece together Moscow's positions and intentions from components of other documents (most notably a line or two in the country's military doctrine), statements from officials, exercises, force structure and the writings of Russia's own specialists and strategists (the military literature is summarized particularly well in an excellent recent two-part series from the Center for Naval Analyses). To be sure, none of us will stop reading the other documents, watching the exercises, reading the papers and listening to what officials say. But it is nice to have it all in one place.
And putting it all in one place is very much what this new document, which I'll be calling "Foundations" for the balance of this essay, does. There is little that is strikingly new here. Rather, Foundations echoes things we have heard from officials, including Russian President Vladimir Putin, and read in formal documents past. But by bringing them all together, it clarifies a few things. It also highlights some seeming inconsistencies. Importantly, as I know you are all wondering, "escalate to de-escalate" as defined by Western analysts and the U.S. Nuclear Posture Review is almost certainly still not Russia's policy, but Foundations alone isn't going to kill the debate.
I will not summarize Foundations or translate it in toto (the translations and paraphrases you'll find here are my own, unless otherwise noted). If you want to read more about what's in it, I commend to you this excellent piece by Nikolai Sokov, along with Dmitri Stefanovich's and Kristin Ven Bruusgaard's and Pavel Podvig's June 2 Twitter threads and discussions, among others. If you read Russian, Kommersant has put out a nice summary. An official translation will surely show up eventually. I expect more smart takes to follow between the time I finish drafting this text and its publication. I also expect (and may contribute to) detailed Talmudic readings in the weeks, months and years to come. In the meantime, however, I'm just going to talk about what jumps out at me, trying not to cover too much of the ground already covered by others, and what I think it means.
Foundations is broken up into four sections. These are:
Essence of deterrence (that is, what deterrence means to Russia)
Conditions under which Russia would shift to nuclear use
Roles of government institutions and agencies
According to the general principles, deterrence is a whole of government effort. Nuclear deterrence is defensive, meant to guarantee Russia's ability to secure its sovereignty and territorial integrity (and that of allies). Nuclear weapons are only for deterrence. Their purpose is to prevent aggression against Russia (and its allies). Use is a last resort.
As Sokov writes, the discussion of deterrence and its essence owes a lot to Thomas Schelling. As he also notes, Foundations underlines that Russia's approach appears centered around deterrence by punishment, in response to aggression, rather than deterrence by denial, or simply making aggression impossible.
Foundations tells us that Russia is looking to deter states and coalitions that view it as a potential threat and have the nuclear or other weapons of mass destruction, or the conventional capacity, to do it harm. It also lists the military dangers that make deterrence necessary. These are not triggers for nuclear use. I interpret the list instead as a delineation of the sorts of things that require Russia to maintain deterrent capabilities, that is, to fear aggression. They include possession and proliferation of nuclear and weapons of mass destruction and associated delivery vehicles by a range of states, deployments of missile defenses, medium and short-range cruise missiles, precision conventional and hypersonic weapons, directed energy weapons, combat UAVs and nuclear-capable systems deployed near Russia by potential adversaries. So, basically, the fact that countries have scary weapons means that Russia needs nuclear deterrence. The list also, notably, includes the deployment of nuclear weapons and delivery systems on the territory of non-nuclear states—this is surely about deployments of U.S. nuclear weapons in Europe. But it's also not new. We have long known Russia's position on NATO nuclear sharing.
Russian nuclear weapons are to be maintained at a minimally sufficient level. This of course, is in the eye of the force-builder. However, those of us who fear arms racing may take some comfort in this subpoint of paragraph 15.
OK, then, what about use? The section on use begins by repeating the formulation in the last two Russian military doctrines (translation from the Russian Embassy in the U.K.): "The Russian Federation shall reserve the right to use nuclear weapons in response to the use of nuclear and other types of weapons of mass destruction against it and/or its allies, as well as in the event of aggression against the Russian Federation with the use of conventional weapons when the very existence of the state is in jeopardy." Like the doctrines, Foundations underlines that the president of the Russian Federation makes any decision to use nuclear weapons. However, unlike the doctrines, it then, in paragraph 19, outlines four conditions that could allow for (not require) nuclear use:
credible information that Russia is under ballistic missile attack (the missiles don't have to be nuclear—this isn't specified—but in many cases, it's hard to tell before they land);
the use of nuclear or other WMD by an adversary against Russian territory or that of its allies;
adversary actions against Russian critical government or military infrastructure that could undermine Russia's capacity for nuclear retaliation (so, for example, a cyber attack on Russia's command and control—or perhaps one that targets Russian leadership could also qualify); and, finally,
conventional aggression against Russia that threatens the very existence of the state.
Some of this is old. But two things are new, or newish. First is the clear statement that Russia can launch under warning of ballistic missile attack. This is in line with Putin's statements, but still notable to see in a formal document. Second, is the equally clear statement that an attack (military or otherwise) on Russia's nuclear, command and related infrastructure, broadly defined, justifies a nuclear response. This has been a matter of speculation, and often assumed to be true. Now it's confirmed.
What about "escalate to de-escalate"? The U.S. Nuclear Posture Review, published in February 2018, asserts that Russia's nuclear strategy is to threaten to use or use nuclear weapons early in a heretofore conventional, lower-stakes conflict for battlefield gain, including by deterring the adversary from further action. The CNA reports, cited above, also note that Russian military analysts write about how threats of escalation can de-escalate conflict, including in the nuclear realm (American and other strategic thinkers, Schelling among them, have also thought about things like this, of course, and not just in the nuclear realm). Russia's naval doctrine talks of the importance of "demonstration of readiness and determination to employ nonstrategic nuclear use" to deterrence. But there's nothing of this sort in paragraph 19 of Foundations (which also makes no distinction between strategic and non-strategic nuclear weapons). Does Foundations, then, disprove the NPR?
Hard-core believers in "escalate to deescalate," will find language in Foundations that would seem to support their arguments. That language is back at the beginning, under General Principles, in paragraph four. After talking about the defensive nature of deterrence, that paragraph states that Russian nuclear deterrence is intended to "[deter] a potential adversary from aggression against the Russian Federation and (or) its allies, and in the case of a military conflict, [preclude] the escalation of military actions and [end] them under conditions acceptable to the Russian Federation and (or) its allies."
So, what's going on? One possible explanation is that from a deterrence standpoint, one threatens what one needs to threaten, but from a use standpoint, the bar is higher. Foundations does, after all, clearly delineate between deterrence and use. But while conditions for deterrence and use may, indeed be different, saying so in a strategic document, which is itself part of the overall deterrence framework, would seem to undermine credibility. The text may be also intentionally ambiguous—paragraph 15 of Foundations lists unpredictability of scale, time, and place of possible use of force as a key principle of nuclear deterrence. Alternatively, the ambiguity may be unintentional—Foundations is surely the product of several agencies in collaboration, although all in all, this six-page document is a fairly tidy text, so I doubt it.
Perhaps more plausibly, the combination of paragraphs four and 15 may be understood as follows: Russia will use nuclear weapons only under the conditions delineated in paragraph 19. That is to say, it will not use them for simple battlefield advantage or to "escalate to de-escalate." First use is allowed only in case of existential threat: to Russia or to its deterrent. But if those conditions are met, and Russia decides to use nuclear weapons, Russia will do so intending to prevent further escalation and end the conflict as favorably (or acceptably) as possible for itself. The American version, usually articulated in the conventional context, is "deter [and]…[s]hould deterrence fail … win." Russia's take seems to include an intermediate step of re-establishing deterrence, and potentially the acceptance of something short of full victory.
That Foundations, one purpose of which is surely to signal intent to other countries, is still going to be read differently by different audiences speaks to the difficulty of communicating strategy clearly. But it also speaks to the importance of trying. Each clarification alters the debate, raises more questions and, in the end, contributes to transparency, better mutual understanding and, yes, deterrence.
Olga Oliker is the program director for Europe and Central Asia at International Crisis Group.
Photo by U.S. Senior Airman Clayton Wear shared in the public domain as a U.S. government work.
The opinions expressed in this article are solely those of the author.
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redpajama_set_name: RedPajamaCommonCrawl


Last competition under the burning sun on Friday was the Trap Mixed Team Competition. 25 five teams participated to this competition which has the official title of European Championship. The team consists of two persons – female and male. Country can send max two team to the competition. After the qualification the competition continues like cup where are quarter and semi finals and finally Bronze Match and Gold Match.
Finally in to Bronze Match met Russia 2 and Slovakia 2. The Bronze match was tight and it was finally needed a shoot off while match ended 37-37. In the of Baku Russian Team won the shoot off 3-2 and won also bronze medal.
In Gold Match met Italy 1 and Slovenia. Italy was finally stronger with result 41-39. The Italian Team consisted of their Olympic Medal athletes Giovanni Pellielo and Jessica Rossi. Pellielo hit 21 and Rossi 20. Slovenia team consisted of Tomaz Blazinsek and Jasmina Macek. Macek hit 22 clays and Blazinsek 17 clays.
"This competition is fun but also hard while you have so many parts in it. Also today's temperature and wind me it difficult for me, but we managed with Jessica (Rossi) a little better than Slovenian team", sighed sweaty Giovanni Pellielo.


Using Fundy Theme, this error (Uncaught TypeError: Object #<HTMLDocument> has no method 'observe' ) occurs when opening each page (show console Log in Chrome).
This error generates pop-up window each time FusionForge's page is opened in IE (depending on IE settings) . So it is really annoying for me.
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text:
Sherlock Holmes A Game of Shadows Movie Review by Chris Stuckmann
Video Creator's Channel Chris Stuckmann
Homes Should One Get Stuck Mine Eyes
Elementary Watson elementary, what do you see everything that because Sherlock Holmes too directed by Guy Ritchie stars Robert Downey Jr. Jude Law Nomi rapist Jared Harris and RachelNK] now I pride myself on not spoiling plots or really anything in my reviews and I'm gonna do my best to do that here. I'm just gonna sum up the plot quickly because I don't want to really get too much into it because if you're interested in seeing the film already you're going to see it if and if you're not interested you're gonna look at the pie yourself. I don't do it for you but if you don't wanna get spoiled that's great and I'm not going to do it for you. Sherlock Holmes is going up against this guy who has an extremely evil plot that has to do with.
spoiled
With Starting A War And Hes Trying To
avert that obviously in his very special Sherlock Holmes way and that leads him on a great mystery filled with action mystery and suspense, Oh how I've missed you Holmes have you I bet he nursery strips Yeah I really enjoyed the first film. I had a lot of fun with the first movie. I liked the directorial style and that's really the thing. I think kind of hanges on whether or not you will like that film and especially the second one because Guy Ritchie style takes a little bit of getting used to and it's definitely different and it has a very visceral feel to it. Very in-your-face loud a different style than normal and for me that's very commendable because I love seeing something that's different than the average norm, What are we up against here the most formidable.
In Europe, Professor James Moriarty, I Love Sherlock
Holmes-I actually liked him more in the first film I've liked a lot of films lately and to be honest. A lot of people have given me hate saying you're getting too easy on movie or something, but I've never once given a false opinion on a film. If I feel a certain way that's how I'm going to tell you and I love this movie I was really surprised how much fun I had of this movie if you liked the first film if you liked the style the first phone. Then this is going to be just a great fun time for you more than likely it's one of the funnest times. I've had of the movies all year if we can stop him should prevent the collapse of Western civilization New pressure Robert Downey Jr.
eyes elementary watson elementary sherlock
holmes actually liked film
sherlock holmes directed guy ritchie
fun time movies winter sherlock
wanna spoiled great going sherlock
Think is one of the greatest actors we have working today and Jude Law is magnificent in this movie and both of them work so well together. The chemistry in the first film was really good, but it's even better here there's much more of a kind of bromance going on really like yes there they're a team and you can really feel their relationship. There's a great emotional way to their relationship and I really dug that aspect of the film also the action in this movie is very very well done an extremely well choreographed and filmed well you too concerned citizens Mr.
Holmes I feeling you're in danger. There's a particular set piece near the latter half of the film involving a forest chase that actually blew my mind and is probably the best action scene. I've seen in theaters all year having seen Mission Impossible 4.
Yet I Mean My Mouth Was Hanging
open a little bit. I was very impressed the villain was very strong too. He was extremely evil and you really could feel that undercurrent, especially whenever him and Sherlock Holmes would clash whether physically or through dialogue extremely riveting dialogue in this movie hilarious. This is much funnier than the first film, which was also funny, but I am seriously from seeing to seem consistent laughs really good movie extremely surprised are you sure you want to play this game.
Im Afraid Your Goose.
Oh dear great great production design beautiful costumes great set pieces lots of fun if you want a fun time with the movies this winter Sherlock Holmes to check it out. I'm going to give Sherlock Holmes to an a very surprised just make it round that's a that comes so let me know down it's stuck when squared did you like the first Sherlock Holmes film or what's your favorite Guy Ritchie film Let me know I would like to know your thoughts if you like this review you can subscribe to my channel and get stuck my eyes.
I pride myself on not spoiling plots or really anything in my reviews and I'm gonna do my best to do that here . I'm just gonna sum up the plot quickly because I don't want to really get too much into it because if you're interested in seeing the film already you're going to see it . If you're not interested you're gonna look at the pie yourself.& I had a lot of fun with the first film. I liked the directorial style and that's really the thing. I think kind of hanges on whether or not you will like that film and especially the second one because Guy Ritchie style takes a little bit of getting used to and it's definitely different and it has a very visceral feel to it . Professor James Moriarty, in Europe, I love Sherlock Holmes-I actually liked him more in the first movie.& In Europe, Professor James Holmes- I love Professor James Mollarthur, I . actually liked his more in…. Click here to read more and watch the full video
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text:
LDS Discussions Blog
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FAIR Mormon's New Approach to Problems with Church History
I've been thinking a bit lately about the FAIR Mormon "This Is The Show" videos and how they attack both the CES Letter and Mormon Stories on such a personal level. If I had more time I'd do a more robust write-up, but work is beating me down this month so this will have to do.
Since FAIR Mormon has now called Jeremy Runnells and John Dehlin "homewreckers for profit," I wanted to respond as an inactive member of record in the Church of Jesus Christ of Latter-day Saints how stupid, misguided, and dishonest of an argument this is.
The thing that FAIR Mormon and their "TITS" videos don't understand is that the information in the CES Letter and Mormon Stories are NOT about Jeremy Runnells or John Dehlin - at least they aren't to me and almost anyone I've talked to in any depth since starting this website.
When I first started down the rabbit hole, I came across the CES Letter because I was using Google to research problems I always knew were there. It blew my mind and the way it went through the different issues both efficiently and in a logical, chronological way just makes it impossible to use apologetics to make it all work.
Is the CES Letter perfect? No, and there are some areas I would absolutely change after reading the rebuttals from FAIR Mormon, Jim Bennett, etc. But that said, even those problems (the maps and plagiarism ones early on seem to be the most problematic) do not change the bigger issues with church history such as the Book of Abraham, DNA, Book of Mormon problems, and, of course, polygamy and racism.
After I read the CES Letter, I made the mistake so many do which is to just blurt everything I learned to my believing spouse, which is always the wrong approach. But she asked me to read the FAIR Mormon response, which I did and it made a lot of sense. But the problem with apologetics came when I read the CES Letter's response to FAIR Mormon and then read FAIR Mormon's response a second time, and then you could see the games apologists play with quotes, sources, and meanings of words.
Once I dug into both the CES Letter and FAIR Mormon, I started listening to podcasts and came across Mormon Stories quickly. The thing about Mormon Stories is that there are so many of them, so you can choose what really speaks to you. For me it was listening to all of the episodes about historical and doctrinal problems. Don't get me wrong - there are some incredibly powerful episodes about the experience of those who leave, but early on I just wanted to get to understanding how we know if the church is true or not.
And just like the CES Letter, the information on Mormon Stories isn't perfect. Sometimes you hear a guest (or even John) say something that isn't 100% correct, but again the overwhelming majority (and I mean overwhelming) of the claims, sources, and facts cited on Mormon Stories are accurate.
When I first started listening to Mormon Stories, my favorite podcasts were the episodes that dealt with the Gospel Topics Essays, Dr. Michael Coe talking about the archaeological problems for the Book of Mormon, Brent Metcalfe, and so many others that dealt with the historical truth claims of the church.
What I'm trying to say here is that both the CES Letter and Mormon Stories are not about Jeremy and John - they are about the church's truth claims and how they stack up to the evidence. The CES Letter did a great job of taking something we were conditioned by the church to think was too complicated for our little, childish minds to understand and made it accessible and consumable, and that's why the church and apologists are terrified of members discovering it on their own. It's never been about Jeremy Runnells, but the approach is that if you can destroy Jeremy, you can hopefully make members afraid to read what he has put forward that has helped so many discover the truth.
And the same is true for Mormon Stories. It's not about John Dehlin - he's the host and is obviously crucial to Mormon Stories, but the power comes from his ability to create a vehicle for so many scholars, former church leaders, and members to tell their story to others so that members and listeners know they aren't crazy for having doubts, and that they aren't alone for wanting to leave a church that isn't true.
But just like the CES Letter, apologists try to make Mormon Stories about John Dehlin so they can tear it down. It's the same approach - if you make members think that John Dehlin has been "taken over by the adversary," you can make members afraid to listen to his podcast out of fear they'll be taken over too. And this is not exaggeration, I've seen this happen with some I know who will not listen to anything John Dehlin puts forward just like Jeremy Runnells.
The problem is that even if you take all of John Dehlin's audio out of Mormon Stories, the episodes are still incredibly powerful and important because John has brought people from so many backgrounds to explore the church's truth claims whether it's the Book of Abraham with Dr. Robert Ritner, three geneticists who dissected the Book of Mormon DNA essay, or John Hamer and Dan Vogel to explain how the Book of Mormon came to be. I could go on all day - there are so many episodes that I wish every member of the church could watch.
Apologists know how powerful both the CES Letter and Mormon Stories are to assessing the truth claims of the church, which is why they seek to make it personal with attacks about their motives and character. It's really shameful, but it's not a surprise given that apologetics simply do not hold up when you dig below the surface. I've written on too many talks by high level church leaders where they not only demonize doubts, but they attempt to make those around you with doubts toxic to the youth of this church.
As noted above, FAIR Mormon recently called John Dehlin and Jeremy Runnells "homewreckers for profit" as their rationale for their TITS videos where they launch one ad hominem attack after another to "destroy" the CES Letter. The problem is that as we've shown in reviewing the Seer Stone video and now the Book of Abraham video is that their scholarship is, to be blunt, terrible and their approach is insulting to the viewers that they are trying to manipulate by poisoning the well to keep them from researching from non-correlated sources.
Furthermore, if the church really wants to make te argument that people who take money can't be trusted about the church, what do we say about church educators who have no other career than in the church. Ask anyone who leaves the church - once you spend your life defending the church with poor apologetics and scholarship, no outside instututions want to hire you.
What about church leaders, who are given homes, lucrative seats on church owned boards of directors, pensions, and six figure stipends to keep members in the church? Or how about apologists that write apologetic books that we can prove are dishonest, but go on book tours, given interviews to church media, or and are paid for columns or projects in church media?
The point is that we can not measure the accuracy of the claims made by the people making it or how they are compensated for it. It's an ad hominem attack, and while it's really effective to those sympathetic to your cause, it does nothing to address the underlying facts and only further shows that your own argument cannot hold up to basic scrutiny.
If the church was true, they would tell members to take their claims for a test drive and make sure they hold up for themselves. Instead we have talk after talk telling us that doubts are bad, that leaving the church is like suicide, and that those historical issues are just 'secondary' questions.
What is the church so afraid of? Why are they funneling so much money to FAIR Mormon to produce videos like this instead of having actual non-Mormon scholars on their various media outlets (Church Newsroom, Deseret News, church magazines, BYU-TV, KSL, etc) confirm their truth claims? You know the answer to that question, and so do they.
At the end of the day, you can prove that the Mormon church is not true. There is simply no way around it - just in our recent section on biblical scholarship you can see that the Book of Mormon, Abraham, and Moses are not historical books, and that's before we even get into the texts of these books on their own.
We've also done a two part overview on the Book of Abraham which used the Mormon Stories interview with Dr. Robert Ritner extensively along with the series from biblical scholar Dr. David Bokovoy both with Mormon Stories and Radio Free Mormon. That information would not have been accessible to me without John Dehlin (and RFM), which again is why the church wants members to be afraid of him personally so that they never listen to him or the many scholars he has brought on to discuss these issues.
In the coming weeks/months we are going to do another 10-15 overview pages that go through the truth claims of the Book of Mormon, Joseph Smith, and the church itself, and each one will show why the apologetics of FAIR Mormon are willfully deceptive, and why these recent "TITS" videos are not just awful in tone, but sloppy and dishonest in their scholarship.
This ended up being a bit longer than I thought it would, but I just hate this tactic that the church and its apologists use which is to attempt to demonize and destroy anyone who speaks out against the church, whether their criticisms are true or not. In this case, Jeremy Runnells and John Dehlin are providing members with information they've been taught all their lives were "anti-Mormon lies" only to find out their actually true and provable.
And the church sees that they are very slowly losing control over members, and that they can no longer control the information like they could before the internet. I only wish I had access to this information when I joined as a convert 20+ years ago, because I could've saved a whole lot of time, money, and distress with just a few hours of Google searches when I was more open to this information than when I finally jumped into the rabbit hole 20 years later.
One last note is that our website is going to have a lot of new information up that I really think will be helpful and powerful to those with questions, and I am doing this as a member of record and without taking a dime from anyone. If FAIR Mormon or the church wants to attack me, they're going to need to do it on the merits, which is why they're never going to bother trying. But I'm open anytime to a conversation about these issues, so if anyone from the church is reading please message me anytime (email is ldsdiscussion@gmail.com). I promise I'm respectful and honest in my work, and you know I'm not doing this for the money so let's talk.
Merry Christmas and can't wait to see you all in 2021!
Please check us out on Twitter and Facebook for more updates and random musings.
Back to the LDS Discussions's Blog


text:
Der Monroe-Effekt bezeichnet einen starken Aufwind an Hochhausfassaden.

An heißen Tagen bilden sich am Fuße hoher Häuser oft böige Aufwinde, die am Gebäude von unten nach oben strömen. Passanten kann beim Durchqueren solcher Zonen die Bekleidung hochgeweht werden. Der Name stammt von einer bekannten Szene im Film Das verflixte 7. Jahr, in der Schauspielerin Marilyn Monroe über einem U-Bahn-Lüftungsgitter steht und ihr Rock hochgeweht wird. Im Wohnungsbau wird der Monroe-Effekt bisweilen für Überanspruchungsschäden an Fensterbänken verantwortlich gemacht.

Unterschieden werden muss der Monroe-Effekt vom ähnlich ausgesprochenen Munroe-Effekt, der die partielle Fokussierung von Explosionsenergie bezeichnet.

Literatur
 Annette Kessler: Vom Small Talk zur Konversation: Unterhaltsames aus Kunst, Literatur und Musik von A bis Z. GABAL Verlag GmbH, Offenbach 2010, ISBN 3869361190, S. 109.
 Günter Kohlbecker: Sanierung im Mietwohnungsbau: Wirtschaftliche und energetische Umsetzung. Beuth Verlag, 2011, ISBN 3410177086, S. 135.
 Sandy Gow, Bonar Alexander Gow: Roughnecks, Rock Bits And Rigs: The Evolution Of Oil Well Drilling Technology In Alberta, 1883–1970. University of Calgary Press, Calgary 2005, ISBN 155238067X, S. 134.

Wind
Marilyn Monroe

redpajama_set_name: RedPajamaWikipedia


No one's quite sure just why the poles are mood elevators. It may be because working your arms as well as your legs releases more endorphins (a group of substances in the body that relieves pain, controls your body's response to stress and determines mood) or other chemicals in the brain than walking without them. Or maybe it's just fun to have a variation to usual walking.
Adding the poles can be pretty taxing, so gradually increase the time you use them. For example, if you regularly walk 30 minutes, start by using the poles for just five of those minutes the first week. Add five more minutes each week until you're walking all 30 minutes with the poles. Use two poles at a time -- one in each hand. Doing so supports each knee.
Shop for trekking poles at sporting goods or outdoor stores. The poles come with aluminum or carbon fiber shafts and sport features such as grips, adjustable height, straps and shock absorption systems. Choose what's most comfortable for you.
NOTE: People with upper-extremity injuries such as carpal tunnel, tennis elbow or shoulder joint problems shouldn't use walking poles.


text:
Q: Javascript won't show up I was trying to include my first Javascript snippet to see how it works in a browser. But when I add these lines in my HTML code (directly in the body, even if I know there are better ways), nothing happens. I save the file as HTML and open it up in Chrome

var greeting = function(name) {
  console.log("Great to see you" + " " + name);
};
greeting("Waldo")

A: It does works, tho you need to access the JS console, which is inside the DevTools of chrome.
If you want a more in your face approach, change it for alert.

A: Replace console.log with alert, put a semicolon after
    greeting("Waldo");
And remove the white space between
    function (name)
So it will be
    function(name)

A: console.log("stuff") logs a message to the developer console. You open the console through the menu on most browsers (on Chrome for example hit menu->more tools->developer tools->console). This will show you the result of any console.logs as well as errors, and you can run Javascript code in the console.
As others have suggested, alert("stuff") is a good replacement if you don't want to deal with the console. It will show a dialog box (popup) instead of printing the text to the console.

A: First: are you wrapping these lines of code with the <script>....</script> tags?
If so, just open your browser console with F12 and you should see the result of the function.

redpajama_set_name: RedPajamaStackExchange


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text:
\section{Introduction}
Ever since the earliest detections of non-thermal emission from
jet-type astrophysical sources astrophysicists have conjectured
upon its origin. Today, it is widely believed that Fermi processes,
where particle acceleration occurs as a consequence of multiple
scattering of energetic particles off magnetic turbulence with
a small energy change in each event, are responsible for the
production of the non-thermal powerlaw particle distributions as
required by the observed synchrotron and inverse Compton emission
properties of these jets.
First-order Fermi acceleration at strong nonrelativistic shocks,
observationally well established to take place in the shells of
supernova remnants (e.g., Aharonian et al.,~2004), can, for example,
naturally account for the commonly required powerlaw particle
spectra $N(\gamma) \propto \gamma^{-s}$ with spectral indices $s
\simeq 2$ and is also a sufficiently fast and efficient mechanism.
On observational grounds such an interpretation is strongly supported
by (i) the fact that the knotty features detected in extragalactic
jets can be directly identified with sites of strong shock formation,
and (ii) by the multiple detection of characteristic variability
patterns (e.g., spectral index hysteresis) associated with efficient
first-order Fermi acceleration in AGN-type jets (Kirk et al., 1998).
Recent high-resolution studies of extragalactic jets, however,
indicate that first-order Fermi acceleration alone, localized
by its very nature, cannot satisfactorily account for the
detection of extended high-energy emission. In the case of the
quasar 3C~273, for example, the optical spectral index is found
to vary only smoothly along the (large-scale) jet with no signs
of strong synchrotron cooling at any location in the jet, e.g.,
between knots, contrary to expectations from shock acceleration
scenarios (Jester et al., 2001; Jester et al., 2005), thus
suggesting the need of a continuous stochastic re-acceleration
mechanism operating all along the jet.
Shear and/or second-order Fermi particle acceleration, although
possibly swamped by first-order Fermi processes in the vicinity
of a flow discontinuity, appear to be the most natural candidates
that may account for these observations.\\
Here we analyse some of the essential properties of Fermi particle
acceleration processes and discuss their relevance for different
astrophysical jet sources. We wish to note that we are focusing on
mechanisms operating {\it within} a jet and not at its working
surface (hot spot).

\section{Fermi acceleration processes}\label{fermi}
Fermi particle acceleration (Fermi, 1949) is essentially
based on the fact the energetic particles (velocity $v \sim c$)
can gain energy by elastically scattering off magnetic turbulence
structures or irregularities moving with some characteristic
velocity $\vec{u}$. Following a simple microscopic treatment and
assuming energy to be conserved in the comoving scattering frame,
the energy change of a particle due to collision is simply given
by
\begin{equation}\label{gain}
\Delta \epsilon:=
\epsilon_2 -\epsilon_1 = 2 \Gamma^2 (\epsilon_1 u^2/c^2
                         -\vec{p}_1 \cdot \vec{u})\,,
\end{equation} where $\Gamma=(1-u^2/c^2)^{-1/2}$ is the Lorentz factor,
$\vec{p}=E \vec{v}/c^2$ the particle momentum and the indices 1
and 2 denote particle properties before and after scattering.
A particle thus gains or loses energy depending on whether it
suffers head-on/approaching ($\vec{p_1} \cdot \vec{u} < 1$)
or following/overtaking ($\vec{p_1} \cdot \vec{u} > 1$) collisions.
Based on these considerations the following cases may be
distinguished:

\subsection{Shock or first-order Fermi acceleration}
Suppose that a strong (nonrelativistic) shock wave propagates
through the plasma. Then in the frame of the shock the conservation
relations imply that the upstream velocity (ahead of the shock) is
much higher than the downstream velocity (behind the shock), i.e.,
$u_u/u_d = (\gamma_h+1)/(\gamma_h-1)$, with $\gamma_h >1$ denoting
the ratio of specific heats, so that the two regions may be regarded
as two converging flows. Hence, in the upstream [downstream] rest
frame the plasma from the other side of the shock (downstream
[upstream]) is always approaching with velocity $u=u_u-u_d$, so
that to first order there are only head-on collisions for
particles crossing the shock front. The acceleration process,
although stochastic, thus always leads to a gain in energy, so
that for magnetic turbulence structures virtually comoving with
the plasma flow, the energy gain [eq.~(\ref{gain})] becomes first
order in $u/c$, i.e.,
\begin{equation}
 \frac{\Delta \epsilon}{\epsilon_1} \propto \frac{u}{c}\,.
\end{equation}
The acceleration timescale $t_{\rm acc}$ for diffusive shock
acceleration depends on both, the upstream and downstream residence
times (Drury, 1983). In general, for a useful order of magnitude
estimate $t_{\rm acc} \sim 3 \kappa/u_s^2$ (Kirk and Dendy, 2001),
with $u_s$ the shock speed measured in the upstream frame and
$\kappa$ the spatial diffusion coefficient. Particularly, for
quasi-parallel shocks with $\kappa = \kappa_d \simeq \kappa_u$ one
finds $t_{\rm acc} \simeq 20\,\kappa/u_s^2$ (e.g., Protheroe and
Clay, 2004), so that in the quasi-linear limit $|\delta B| \stackrel{<}{\scriptstyle \sim} B$,
where $\kappa \stackrel{<}{\scriptstyle \sim} \kappa_B \simeq r_g\,c/3$,
\begin{equation}\label{t_shock}
t_{\rm acc} \stackrel{>}{\scriptstyle \sim} 6 \frac{\gamma\,m\,c}{e\,B}
                  \left(\frac{c}{u_s}\right)^2\,.
\end{equation} In theory, much faster acceleration may be achieved for
quasi-perpendicular shocks, where -- assuming quasi-linear
approximation ($|\delta B| \ll B$) to hold -- the (perpendicular)
diffusion coefficient $\kappa$ can be significantly smaller than
the above quoted Bohm limit (Jokipii, 1987). However, for realistic
astrophysical applications such a situation seems at least
questionable given recent numerical results which show that cosmic
ray streaming at a shock front can lead to strong self-generated
turbulence beyond the quasi-linear regime (Lucek and Bell, 2000).\\
Fermi acceleration at (unmodified) nonrelativistic shocks is known
to produce powerlaw particle spectra $N(\gamma) \propto \gamma^{-s}$,
which are essentially independent of the microphysics involved and
only dependent on the shock compression ratio $\rho=u_u/u_d$ (where
$1 < \rho \leq 4$), i.e.,
\begin{equation}
  s=\frac{(\rho+2)}{(\rho-1)}\,,
\end{equation} so that for strong shocks ($\rho=4$ in the test particle limit)
the famous $s=2$ result is obtained (Drury, 1983; Blandford and Eichler,
1987). Note that incorporation of non-linear effects (e.g., strong
shock modification) usually suggests values $s < 2$ at high energies
(Berezhko and Ellison, 1999). On the other hand, incorporation of
anomalous (non-diffusive) transport properties associated with the
wandering of magnetic field lines, may efficiently reduce cross-field
propagation and thus allow values up to $s=2.5$ (Kirk et al., 1996).\\
To undergo efficient first-order Fermi acceleration at non-relativistic
shocks electrons already have to be preaccelerated up to seed Lorentz
factors $\gamma_e > m_p/m_e\,(V_A/c)$ (ion cyclotron resonance condition).
Recent simulations suggest that this "problem of injection" may possibly
be resolved by electrostatic wave (ESW) surfing  -- when ESWs, excited by
streaming ion beams, saturate by trapping electrons, thus transporting
them across the magnetic field --  and/or acceleration due to ESW collapse
(McClements et al., 2001; Dieckmann et al., 2004).

\subsection{Second-order Fermi acceleration}
Suppose that the scattering centres have a non-negligible random
velocity component. In the absence of dominant shock effects (see
above), energetic particles will thus experience both head-on and
overtaking collisions, i.e., lose and gain energy. However, as the
rate of collisions is proportional to $|\vec{v_1}-\vec{u}|/v_1
\simeq (1-\vec{v}_1 \vec{u}/v_1^2)$, there is a higher probability
for head-on compared to overtaking collisions, which gives an average
energy gain per collision that is second order in $u/c$, i.e.,
\begin{equation}
 \frac{<\Delta\epsilon>}{\epsilon_1} \propto
                         \left(\frac{u}{c}\right)^2
\end{equation} when averaged over all momentum directions. Second-order Fermi
acceleration thus represents a classical example of a stochastic
acceleration process due to many small, nonsystematic energy changes.
As such it can be described by a diffusion equation in momentum space
(Skilling, 1975; Melrose, 1980), i.e., the isotropic phase space
distribution (averaged over all momentum directions) evolves according
to
\begin{equation}\label{diffusion}
 \frac{\partial f(p)}{\partial t} = \frac{1}{p^2}\frac{\partial}{\partial p}
                 \left(p^2 D_{p}(p) \frac{\partial f(p)}{\partial p}\right)\,,
\end{equation} with $D_{p}(p) \propto <(\Delta p)^2>$ the diffusion coefficient
in momentum space. A statistical treatment taking the small anisotropy
of the particle distribution in the laboratory frame into account
allows proper calculation of the Fokker-Planck coefficients (Duffy
and Blundell, 2005) and for $v \sim c$ gives $D_p =(u/c)^2 p^2/(3 \tau)
\propto p^2/\tau$, where $\tau \simeq 1/(n\,\sigma\,c)$ is a mean
scattering time and $n$ is the number density of scatterers. For
the scattering off forward and reverse propagating Alfven waves a
similar expression can be derived (Skilling, 1975; Melrose, 1980;
Webb, 1983), i.e.,
\begin{equation}
  D_p \simeq \frac{p^2}{3 \tau} \left(\frac{V_A}{c}\right)^2\,,
\end{equation} where $V_A =B/\sqrt{4\pi\rho}$ is the Alfven velocity. This
implies a characteristic acceleration timescale
\begin{equation}\label{acc}
t_{\rm acc}=p^3 \left[\frac{\partial}{\partial p}\left(p^2 D_p\right)
            \right]^{-1}
           = \frac{3}{(4-\alpha)}\left(\frac{c}{V_A}\right)^2 \tau
\end{equation} for $\tau = \lambda/c \propto p^{\alpha}$. Comparison with
the results for diffusive shock acceleration shows that second-order
Fermi acceleration is typically a factor of order $(u_s/V_A)^2$
slower than first-order Fermi acceleration.\\
Second-order Fermi acceleration is usually expected to lead to
particle spectra $N(\gamma)\propto \gamma^{-s}$ that are typically
flatter than those produced by standard strong shock acceleration,
i.e., $s<2$ (cf. also Virtanen and Vainio, 2005). For example,
adding both a monoenergetic source term $Q\,\delta(p-p_0)$ and a
particle loss term $-f/T$ on the rhs of eq.~(\ref{diffusion}),
assuming $\alpha=0$ and steady state, one finds
\begin{equation}
  s=\frac{3}{2} \sqrt{1+16\,t_{\rm acc}/(9\,T)} -\frac{1}{2}
\end{equation} above $p_0$, so that for $T \gg t_{\rm acc}$ for example, one
has $N(\gamma)\propto \gamma^{-1}$.

\subsection{Gradual shear acceleration}
Consider now the case where the magnetic turbulence structures
are embedded in a gradual shear flow $\vec{u}=u_z(x)\vec{e}_z$,
assuming their random velocities to be small compared to the
characteristic shear velocity. Particles traveling across the
shear thus encounter scattering centres with different (although
non-random) local velocities $u_z(x)$. Similar to the case of 2nd
order Fermi acceleration, the average energy gain per collision
becomes second order in $\tilde{u}/c$, where $\tilde{u} = (\partial u_z/
\partial x) \lambda$ denotes the characteristic relative velocity of
the scattering centres, $\lambda \simeq c \tau$ is the particle
mean free path and $\tau$ is the mean scattering time, i.e., one
finds (cf. also Jokipii and Morfill, 1990)
\begin{equation}
 \frac{<\Delta \epsilon>}{\epsilon_1} \propto
               \left(\frac{\partial u_z}{\partial x}\right)^2 \tau^2\,.
\end{equation}
Again, as a stochastic process shear acceleration can be described
by a diffusion equation in momentum space, i.e., an equation of
type eq.~(\ref{diffusion}). For nonrelativistic gradual shear
flows a proper statistical treatment (Rieger and Duffy, 2006)
gives
\begin{equation}
D_p = \tilde{\Gamma} p^{2} \tau \propto p^2 \tau\,,
\end{equation} where $\tilde{\Gamma}=(\partial u_z/\partial x)^2/15$ is the shear
flow coefficient and $\tau =\tau_0\,p^{\alpha}$ is the mean
scattering time. This implies a characteristic acceleration
timescale [cf. eq.~(\ref{acc})]
\begin{equation}\label{shear}
t_{\rm acc} = 1/([4+\alpha]\,\tilde{\Gamma}\,\tau)
\end{equation} which, in contrast to first- and second-order Fermi, is
inversely proportional to the particle mean free path $\lambda
\simeq \tau/c$. Eq.~(\ref{shear}) can be generalized to the
relativistic case by replacing $\tilde{\Gamma}$ by its
relativistic counterpart (Rieger and Duffy, 2004, eq.(3)).
In particular, for a (cylindrically collimated) shear flow
decreasing linearly with radial coordinate from relativistic
to nonrelativistic speeds over a distance $\Delta r=(r_2-r_1)$,
the maximum acceleration timescale is of order
\begin{equation}\label{t_shear}
t_{\rm acc} \simeq \frac{3 (\Delta r)^2}{\gamma_b(r_1)^4
           \lambda\,c}\,\
\end{equation} where $\gamma_b(r)$ is the local bulk Lorentz factor
of the flow.\\
In the simplest case, assuming quasi steady state conditions
and monoenergetic injection, the functional form of the local
particle distribution $N(p) \propto p^2\,f(p)$ becomes
\begin{equation}
 N(p) \propto p^{-(1+\alpha)}
\end{equation} above $p_0$ for $\alpha >0$ (Berezhko and Krymskii,
1981; Rieger and Duffy, 2006). From an astrophysical point of
view, acceleration becomes essentially non-gradual when the
particle mean free path becomes larger than the width of the
transition layer. In this case results from the study of
relativistic non-gradual shear flows (e.g., Ostrowski, 1990)
can be employed to analyse issues of maximum energies and
resulting particle distributions.

\section{Application to astrophysical jet sources}
Apart from lateral particle escape and limited jet activity, radiative
synchrotron losses represent one of the most servere constraints for
the acceleration of energetic particle in astrophysical jets. We may
estimate the maximum achievable particle energy in the presence of
synchrotron losses by equating the isotropic synchrotron cooling
timescale $t_{\rm cool}=(9\,m^3\,c^5)/(4\,\gamma\,e^4\,B^2)$ with
the corresponding acceleration timescale. For non-relativistic shock
acceleration this results in a maximum comoving Lorentz factor
(provided $r_g(\gamma_{\rm max})$ is still smaller than the width
of the jet) of order
\begin{equation}\label{g_shock}
   \gamma_{\rm max}^{1st} \simeq 9\cdot 10^9 \left(\frac{1\,
                     \mathrm{G}}{B}\right)^{1/2}
                     \left(\frac{m}{m_p}\right)\,
                     \left(\frac{u_s}{0.1\,\mathrm{c}}\right)\,
\end{equation} with $m_p$ the proton mass, whereas in the case of second order
Fermi with $\lambda \simeq r_g$ one finds
\begin{equation}\label{g_2nd}
   \gamma_{\rm max}^{2nd} \simeq 2\cdot 10^8 \left(\frac{1\,
                          \mathrm{G}}{B}\right)^{1/2}
                          \left(\frac{m}{m_p}\right)\,
                          \left(\frac{V_A}{0.001\,\mathrm{c}}\right)\,\,.
\end{equation} For $\lambda \sim r_g$ the acceleration timescale in a gradual
shear flow [e.g., eq.~(\ref{t_shear})] scales with $\gamma$ in the
same way as the cooling timescale, so that radiative losses are no
longer able to stop the acceleration process once it has started to
operate efficiently. For a linearly decreasing flow profile efficient
acceleration thus becomes possible if the shear is sufficiently strong,
i.e., provided the relation
\begin{equation}\label{r_shear}
  \Delta r \stackrel{<}{\scriptstyle \sim} 0.1 \,\gamma_b(r_1)^2 \left(\frac{m}{m_p}\right)^2
           \left(\frac{1\, \mathrm{G}}{B}\right)^{3/2}\,\,\mathrm{pc}\,
\end{equation} holds. These considerations suggest the following:

\subsection{Relativistic AGN jets}
In the case of relativistic AGN jets, diffusive shock acceleration
({\it first order Fermi}) processes represent the most efficient and
plausible mechanism for the origin of the observationally required
non-thermal powerlaw distributions in their inner (sub-parsec scale)
jets. For characteristic parameters, e.g., $u_s \sim 0.1$ c, $B \sim
0.1\, b_0$ Gauss, maximum electron Lorentz factors $\gamma_{\rm max}
\stackrel{<}{\scriptstyle \sim} 10^7\,b_0^{-1/2}$ [cf. eq.~(\ref{g_shock})] may be reached
suggesting that for blazar-type sources with $\gamma_b \sim 10$ an
electron synchrotron contribution up to $\nu_{\rm obs} \sim 10^5
\gamma_b\,\gamma_{\rm max}^2\,b_0 < 2 \cdot 10^{20}\,$ Hz, i.e., well
in the hard X-ray regime, may be possible, provided IC losses do not
dominate. Furthermore, the variability in the high energy regime may
be very fast if associated either with $t_{\rm acc}$ or $t_{\rm
cool}$. One expects a similar expression for the acceleration
timescale [eq.~(\ref{t_shock})] to hold if shocks in blazar-type
jets are mildly relativistic ($u_s \stackrel{>}{\scriptstyle \sim} 0.3$ c), although the
spectral index may then be somewhat steeper, i.e, $s > 2$, and the
explicit results more dependent on the exact scattering conditions
(e.g., Lemoine and Pelletier, 2003).\\
As noted in the introduction (e.g., see the case of the famous
quasar 3C~273), the situation is somewhat different with respect
to the (collimated) relativistic large-scale jets in AGNs,
\footnote{There is now mounting observational evidence that the
jets of powerful FR~II type sources are still relativistic ($\gamma_b
\sim 5$) on large kpc scales (e.g., Sambruna et al., 2001;
Tavecchio et al., 2000).} where observational evidence suggests that
shock acceleration is not sufficient to account for the observed smooth
evolution of the spectral index. Stochastic acceleration like shear
or second-order Fermi processes may represent the most natural
candidates for distributed acceleration mechanisms operating all
along the jet (Stawarz and Ostrowski, 2000; Rieger and Duffy, 2004).
For a quasi-uniform flow profile with $\gamma_b \sim (3-5)$ and
a characteristic set of parameters, $B \sim 10^{-5} b_0$ G, $b_0
\stackrel{>}{\scriptstyle \sim} 1$ (e.g., Stawarz, 2005) and $V_A \sim 10^8\, b_0$ cm/s,
{\it second-order Fermi} acceleration [eq.~(\ref{g_2nd})] may account
for electrons with maximum Lorentz factor up to $\gamma_{\rm max}
\sim 10^8\,b_0^{1/2}$, corresponding to synchrotron emission up
to $\nu_{\rm obs} \sim 5 \cdot 10^{17}\, b_0^2 \,\mathrm{Hz}
\stackrel{<}{\scriptstyle \sim} 2\,b_0^2$ keV. Neglecting inverse Compton losses for a
moment, it seems possible that synchrotron emission from
electrons accelerated via second-order Fermi processes can, at
least in principle, account for the observed extended emission in
the optical (Jester et al., 2001), and perhaps even in the
Chandra X-ray regime (cf. Harris and Krawczynski, 2006). If this
is indeed the case, the radiating electron distribution $N(\gamma)
\propto \gamma^{-s}$ is likely to consist of at least two components:
One, localized at the observed knots and corresponding to strong
shock acceleration with spectral index $s \simeq 2$, and one,
distributed in between knots and associated with second order
Fermi processes and flatter spectral index $s<2$. It is likely,
however, that the real situation is much more complex. There is
strong evidence, for example, that in reality astrophysical
jets do not possess a simple uniform flow profile as often used
for spectral modelling. In particular, the density and velocity
gradients associated with extreme astrophysical environments
are likely to result in a non-negligible velocity shear across
the jet. In the case of AGN such shear flows are indeed
observationally well-established, e.g., see Laing \&
Bridle~(2002) and Laing et al.~(2006) for recent observational
results and modelling, and Rieger \& Duffy (2004) for a recent
review of the phenomenological evidence. For the characteristic
parameters specified above, eq.~(\ref{r_shear}) then suggests that
on kiloparsec scales efficient {\it shear acceleration} of
electrons may be possible provided the velocity decreases
significantly on radial scales $\Delta r_e \stackrel{<}{\scriptstyle \sim}$ several
percent of the total jet width $r_j \sim 1$ kpc. Essentially no
such constraint applies to protons (i.e., $\Delta r_p \sim r_j$,
cf. eq.~[\ref{r_shear}]), so that compared to the case of
electrons efficient proton acceleration should be much more
common. These considerations have interesting observational
consequences: (i) Suppose that the velocity shear in the
large-scale jet is sufficiently strong (e.g., significant
velocity decay over $\Delta r_e \sim$ several percent of
$r_j$) to allow for efficient electron acceleration,
the required high energy seed particles ($\gamma \stackrel{>}{\scriptstyle \sim} 10^6\,b_0$)
being provided by first and second-order Fermi processes. Even for
the simplistic case of $V_A$ independent of $r$, shear acceleration
will then begin to dominate over second-order Fermi processes for
electrons with $\gamma \stackrel{>}{\scriptstyle \sim} 10^8\,(\Delta r/10\, \mathrm{pc})\,
(V_A/0.01\,c) \,b_0$, resulting in a third radiating electron
component with local index $s \simeq 2$. If this is indeed the case,
the observed spectral index in the optical-UV (probably due to
second-order Fermi acceleration) may well be different from the
one measured in the X-ray regime (likely due to shear acceleration).
(ii) On the other hand, even if the large-scale shear is very weak
(e.g., say $\Delta r \sim 0.3$ kpc) efficient acceleration of
protons remains still possible suggesting that relativistic
gradual shear flows may allow acceleration of protons up to
ultra-high energies of $10^{18}-10^{19}$ eV (where $\lambda
\sim \Delta r$), i.e., well up to the ``angle'' of the cosmic
ray energy spectrum at around  $3 \times 10^{18}$ eV.
Subsequent non-gradual shear acceleration may then reach even
higher proton energies, perhaps even up to $\sim 10^{20}$ eV
(Ostrowski, 1990 and 1998). If so, then one would naturally
expect a change in spectral index around the angle when gradual
shear is replaced by non-gradual shear acceleration usually
associated with flatter particle spectra.

\subsection{Ultrarelativistic GRB outflows}
While there is strong evidence today that GRBs are associated
with collimated ultra-relativistic outflows or jets (Rhoads,
1999; Kulkarni et al., 1999; Greiner et al., 2003), it is still
a matter of ongoing debate whether these jets exhibit a rather
uniform ("top-hat") or a more universal structured ("power-law"
or "Gaussian"-type) hydrodynamical profile (e.g., Rhoads, 1999;
Rossi et al., 2002). In any case, it is commonly believed that
shock accelerated electrons are, via synchrotron radiation
processes, responsible for both, the prompt gamma-ray burst and
its afterglow emission (Piran, 2005): Efficient electron
acceleration at mildly relativistic internal shocks ($\Gamma_s$
of a few) arising from velocity variations in the relativistic
outflow, is usually thought to be behind the powerful burst of
$\gamma$-rays (Rees and M{\' e}sz{\' a}ros, 1994), while
electron acceleration at a decelerating, highly relativistic
($\Gamma_s \gg 1$) external shock is believed to be responsible
for the afterglow emission, peaking successively in the
$\gamma$-rays, X-rays, optical and the radio regime (Rees and
M{\' e}sz{\' a}ros, 1992). Whereas to order of magnitude
accuracy, the acceleration timescale at a mildly relativistic
shock front may be reasonably approximated by the Larmor time,
i.e., $t_{\rm acc} \sim r_g/c$, the acceleration timescale at
highly relativistic shocks may be as short as a fraction $1/
\Gamma_s$ of the (upstream) Larmor time (e.g., Gallant and
Achterberg, 1999; Lemoine and Pelletier, 2003).
The latter result is related to the fact that (for all but
the initial crossing) particles upstream cannot be deflected
beyond an angle $\sim 1/\Gamma_s$ before being overtaken by
the shock. Accordingly, particles can also only gain a factor
of order $\Gamma_s^2$ in energy in the first shock crossing
cycle, whereas the energy gain is reduced to a factor of order
$2$ for subsequent crossing events as particles upstream do not
have sufficient time to isotropise (Gallant and Achterberg,
1999; Achterberg et al., 2001; cf. however also Derishev et
al., 2003). In general the power-law spectral index of the
accelerated particle distribution for ultra-relativistic
shock acceleration is strongly dependent on the exact
scattering conditions. In the case of pitch-angle
diffusion the simulations give $s \sim 2.2 - 2.3$ (e.g.,
Bednarz and Ostowski, 1998; Kirk and Duffy, 1999; Achterberg
et al., 2001; Baring, 2005).\\
It has been suggested by Waxman, that the first- (Waxman, 2004)
and perhaps also second-order (Waxman, 1995) Fermi processes,
known to accelerate electrons in GRB outflows with $\gamma_b
\sim 300$ to gamma-radiating energies, may also allow an
efficient acceleration of protons to ultra-high cosmic ray
energies in excess of $10^{20}$ eV.
While this seems in principle possible, the analysis of the
natural shear acceleration potential in expanding
ultra-relativistic GRB flows (Rieger and Duffy, 2005) suggests
that under a reasonable range of conditions shear acceleration
may be more relevant for the production of UHE cosmic rays
than shock-type acceleration processes. This is illustrated in
Fig.~\ref{plot1}, where we have plotted the critical (comoving)
proton Lorentz factor $\gamma_c'$, defined by $t_{\rm acc}(\rm
shear) = t_{\rm acc}(\rm shock)$, as a function of distance $r$,
assuming an intrinsic magnetic field strength $B=1000\,b_0$ $
(10^{13}\, \mathrm{cm}/r)^{\beta}$ and $\eta\,\xi \simeq 1$
(cf. Rieger and Duffy, 2005, for more details), noting that in
order to achieve UHE greater than $10^{20}$ eV, characteristic
(comoving) proton Lorentz factors of $\stackrel{>}{\scriptstyle \sim} 4 \cdot 10^8$ are
required
\begin{figure}
\centering
  \includegraphics[width=0.49\textwidth]{f1.eps}
\caption{Plot of the critical (comoving) Lorentz factor
$\gamma_c'$ as a function of distance $r$ assuming an internal
shock speed of $\beta_s=0.95$ c. Above $\gamma_c'$ the shear
acceleration timescale becomes smaller than the shock
acceleration timescale, so that proton acceleration by shear
becomes more efficient.}
\label{plot1}
\end{figure}

\subsection{Mildly relativistic Microquasar jets}
Similar to the case of extragalactic AGN jets, Fermi-type processes
are likely to lead to efficient particle acceleration in the scale
down versions of AGNs known as galactic Microquasars (MQs) (Mirabel
and Rodr{\'{\i}}guez, 1999). MQs are (radio-loud) X-ray binary systems
where a compact object (a neutron star or stellar mass black hole)
accretes matter from a normal star in orbital motion around it and
(at least in the low-hard state) produces a (quasi-stable) collimated,
mildly relativistic jet with characteristic bulk velocities in the
range of $0.2-0.9$ c (cf. Gallo et al., 2003) and observed jet lengths
in some sources well in excess of several hundred AUs. The detection of
extended, nonthermal radio emission in MQs substantiate the presence
of relativistic electrons in their jets. Indeed, detailed modelling
reveals that synchrotron emission from relativistic electrons is
likely to be important in the radio up to the soft gamma-ray regime
for a magnetic field close to equipartition (Bosch-Ramon et al., 2006).
Assuming a magnetic field scaling $B(z) = 10^5\,b_0\,(z_0/z)$ G, with
$b_0 \sim 1$ and $z_0 \sim 50\,R_g$ (e.g., Bosch-Ramon et al., 2006),
synchrotron-limited, non-relativistic shock processes ($u_s \sim 0.1\,$c)
give electron Lorentz factors $\gamma_e \stackrel{<}{\scriptstyle \sim} 1.5 \cdot 10^4\,
b_0^{-1/2}\,(z/z_0)^{1/2}$, cf. eq~(\ref{g_shock}), thus allowing for
electron synchrotron emission up to $\nu_{\rm obs} \sim 2 \cdot
10^{19}$ Hz ($\sim 10^5$ eV), whereas the condition of lateral
confinement limits possible maximum Lorentz factors for protons
(electrons) to $\gamma_p \stackrel{<}{\scriptstyle \sim} 7 \cdot 10^4\,b_0$ ($\gamma_e \stackrel{<}{\scriptstyle \sim}
10^8\,b_0$), assuming a typical half-opening angle $\phi \simeq 0.05$
rad. Shock acceleration alone seems thus not to be able to provide the
required high-energy electrons suggested by spectral modelling results,
e.g., see the required high acceleration efficiency in the case of
LS 5039 (Parades et al.~2006). Interestingly,
however, post-acceleration of electrons, occurring on scales larger
than $z/z_0 \sim 10$ [cf. eq.~(\ref{r_shear})] within a strong
($\Delta r_e \sim$ several percent of $r_j$) velocity shear
may provide a possible solution by boosting shock-accelerated
electrons further up to maximum Lorentz factors $\gamma_e \sim 10^6$,
substantiating the notion that SSC (Klein-Nishina) or star IC (Thomson)
may yield VHE $\gamma$-rays possibly reaching several TeV energies
(Paredes et al., 2000). We note that further evidence for particle
acceleration beyond standard first-order Fermi has been suggested
recently (Gupta and B\"ottcher, 2006).

\section{Conclusions}
While the relations derived above essentially rely on a simple
test particle approach, thereby neglecting any back-reaction
effects of the accelerated particles (e.g., strong shock
modification, viscous kinetic energy dissipation or significant
wave damping), we believe that they still allow reasonable order
of magnitude estimates for many cases of interest. Hence, although
there are different physical conditions in the relativistic jets
of AGNs, Microquasars and GRBs, our analysis suggests that
Fermi acceleration processes offer a powerful and attractive
explanatory framework for the origin of the non-thermal particle
distributions required within these sources.
In particular, due to its inverse scaling, $t_{\rm acc} \propto
1/\lambda$, shear acceleration is likely to become important at
high energies and may thus naturally lead to the presence of an
at least two-component energetic particle distribution.

\begin{acknowledgements}
Support by a Cosmogrid Fellowship (FMR) is gratefully acknowledged.
\end{acknowledgements}

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