Have you ever heard of the exoplanet, Tau Boötis b? Well, it was discovered back in 1996 and is one of the closest exoplanets to us. Tau Boötis b is about 51-light-years away and is considered to be a “hot Jupiter” because it is a gas giant orbiting close to its parent star. Now, with the advances in techniques used to scan planetary atmospheres, something else has been discovered about Tau Boötis b: the fact that it has water vapor.
It’s a happy Valentines Day on the surface of Mars. Thanks to the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) team we can check out a collection of heart-shaped surface features.
The European Space Agency’s Herschel Space Observatory has recently discovered that the dwarf planet Ceres has direct evidence of water. Ceres, the largest object in the Asteroid Belt, was detected spouting out plumes of water vapor from two different regions. It’s suggested that this water is possibly coming from volcano-like ice geysers.
With the crazy winter weather warnings today in south Louisiana and even school cancellations for tomorrow, I thought it was an interesting time to find out that the dwarf planet Ceres has an icy surface also. With the help of the Herschel space observatory, scientists have detected an icy surface on the only dwarf planet that resides in the asteroid belt. It was previously suspected that ice existed on Ceres but it had not been conclusively detected until now. Plumes of water vapor are thought to shoot up from Ceres when portions of its icy surface warm slightly. This happens in the portion of the dwarf planet’s orbit that takes it closest to the sun. This is a surprise because, while comets are known to have water jets and plumes, objects in the asteroid belt are not. They also believe that if the ice in the interior of Ceres melted, there would be more fresh water than exists on all of Earth!
Ceres is smaller than a planet but, considering it’s the largest object in the asteroid belt, is obviously larger than an asteroid. When first discovered, Ceres was thought to be a comet, then a planet and of course at some point an asteroid. In 2006, The International Astronomical Union reclassified Ceres as a dwarf planet.
There is no such place as a Mary Lee or Dunkin Donuts over on Mars. At least, not yet. But several days ago the Mars Rover Opportunity caught a mysterious object in its lenses that looked awfully like a jelly doughnut. The strange thing is that it just happened to plop down in front of the camera. If you look at the picture above you’ll see that it’s obviously a before-and-after shot. The picture on the left was taken on December 26 of 2013 and the image on the right was taken 13 days later. The object wasn’t there before. So how did it get there?
Artist’s impression of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. After an extensive mapping phase by the orbiter in August–September 2014, a landing site will be selected for Philae to conduct in situ measurements in November 2014. The image is not to scale; the Rosetta spacecraft measures 32 m across including the solar arrays, while the comet nucleus is thought to be about 4 km wide. (Photo: ESA)
Scientists at the European Space Agency (ESA) sounded Rosetta’s internal alarm clock to reboot the mission after two-and-a-half years of deep space slumber. Once its systems warm up, Rosetta is due to beam a signal back to Earth before it begins to home in on a frozen rock known as 67P/Churyumov-Gerasimenko. It is due to shoot harpoons into the 2.5-mile dirtball before its Philae lander docks on the surface – a move that has never been attempted before.
ESA project scientist Matt Taylor likened the mission to that of the action film Armageddon, in which Bruce Willis lands on an asteroid to save the world from destruction. “We’re not just landing on the Moon, we’re dealing with something dynamic, which is kicking off tons of dust and gas every minute,” he told the Sunday Telegraph. Because Rosetta, which has been sleeping to save power, is so far from Earth, it will take 45 minutes for its signal to reach scientists at mission control. They expect to see a blip on computer monitors between 1730 and 1830 GMT, indicating the spacecraft is up and running again.
Dr. Dan Andrews, a planetary scientist at the Open University in Milton Keynes, said: “We’re waiting to hear Rosetta is alive and healthy. “This wake-up call kicks off a chain of events, during which the spacecraft heats itself up, points itself towards the Sun and gets itself ready. “Remember, this mission is 10 years old – it’s a bit of a stroppy teenager and it’s going to take a while to wake up.” If all goes to plan, Rosetta will arrive at Churyumov-Gerasimenko in August before descending to the comet several months later.
Poor Comet ISON was torn apart as it traveled around the Sun around Thanksgiving this year. And as we mourn the loss of Comet ISON we can still rejoice in the fact that there is another comet to be seen in our night sky with a pair of binoculars. Comet Lovejoy, also known as C/2011 R1, was first discovered by amateur astronomer, Terry Lovejoy, and is known as a long-period comet. This northern-hemisphere object was discovered on September 7 2013 and can currently be seen as it travels from Bootes across the constellations of Corona Borealis and Hercules.
During the last century telescope and image capturing technology grew by leaps and bounds. Astronomers for the first time could peer into the far reaches of space to study the hundreds of billions of galaxies that lie beyond our own. Over the years, astronomers developed a systems of galactic classification that categorized galaxies based on their shape and composition. Edwin Hubble created the original system of classification in the early 1900s, which was later expanded to include various other sub-categories as galactic observations improved. A majority of galaxies fall into the following categories…
These galaxies are spherical or ellipsoid in shape, with very few visible features. They contain up to one trillion stars, and very little interstellar dust and gas. Research has indicated that stars in elliptical galaxies are often very old, which is why the galaxies themselves glow with a yellowish-white hue. Also there is less star formation occurring in this type of galaxy.
Lenticular galaxies can be imagined as a mid category between that of the featureless elliptical galaxies and the dramatic spiral galaxies. These galaxies have a defined disk of gas and dust, as well as a glowing bulge at their middle. They do not exhibit spiral arms, but do have large amounts of gas and dust within their disks. This leads to high amounts of star formation within.
Spiral galaxies have very distinct shape and structure consisting of a central bulge of bright stars, and bright arms. Spiral galaxies contain large amounts of gas and dust, and stars of varying ages. Recent theories have explained that the arms are shaped by slowly rotating matter density waves that compress the interstellar gas and dust triggering star formation.
So what type of galaxy is our own Milky Way? That has proven to be a tricky question to answer, since we live inside of it, we can’t simply take a picture of it as we do with the countless other galaxies in our universe. You can take pictures of your neighbors’ houses from out your window, but you can’t take a picture of your whole house unless you go outside and walk away to get a view. The Voyager Spacecraft launched in the 1970s are the furthest man-made probes, and they have only recently exited the Solar System; we are not anywhere close to taking a picture like this of our home galaxy any time soon.
There are some simple observations anyone can make to help them classify our Milky Way.
1. The Milky Way appears as a thin strip across our sky, which implies that it is a thin disc, rather than a sphere of stars.
2. The center of the Milky Way is visible in the southern sky each Summer. This shows that our galaxy has a definite bulge at its middle.
These facts, paired with other astronomical observations have indicated that our Milky Way is a spiral galaxy. However, the question still remains… How many arms does it have?
The interstellar dust in our galaxy blocks our view of faraway stars in the visual wavelengths. Radio telescopes allow astronomers to see through the dust to identify the locations and motions of these stars. Using this information, astronomers extrapolate the shape of our galaxy. Up until recently, data from the Spitzer Space Telescope indicated that there were two distinct spiral arms (where previous theories had suggested four arms). Spitzer was targeting middle-aged cooler stars like our Sun.
A very recent study that targeted supermassive hot young stars painted a different picture: four arms. Due to the large amount of star formation that occurs in the arms of spiral galaxies, these types of stars are found nearly exclusively in the arms. Though these stars live short lives, the high rate of star formation in the arm regions replenishes the populations of them.
Some astronomers theorize that gravitational forces within the Milky Way may have lead to an uneven distribution of the middle-aged and older cooler stars into two of the arms more than the other two, leading the Spitzer data to indicate two arms. Meanwhile the populations of supermassive hot young stars flourish in all four arms.
Truly understanding our home galaxy is a unique challenge that motivates astronomers world wide. Our picture of our galaxy and the universe beyond continues to evolve as we continue to look outward.
Since the 1970s, String Theory has been fiddled with and tooled around as a means of unifying all fundamental forces and all forms of matter. There’s always been a problem bringing together the calculations of how our world operates on a large scale and of what gravity can affect, and the small quantum world of calculations where things begin to get weird and nearly unpredictable when dealing with small particles like atoms and electrons. The two world’s seem incompatible. The main problem has always been figuring out how gravity fits in to both worlds.
Well, in 1997, theoretical physicist Juan Maldacena proposed a model where the mathematical world of String Theory operated as a hologram and the larger world of the cosmos operated on more of a flatter realm where there is no gravity.
Comet ISON is now officially gone, well, pretty much. The NASA Comet ISON Observing Campaign has issued a memoriam for Comet ISON.
Here is the latest view:
Karl Battams: It may be (almost) gone but comet ISON leaves a legacy of unprecedented data from numerous locations within the solar system! [Image credit: ESA, NASA, Annotations by Karl Battams]