en en en en en en tr en en en da en de en de en de en de en de en en en tr en it en es en es en fr en fr en fr en it en it en hu en nl en nl en is en pl en pt en pt en sq en hbs_lat en fi en sv en tr en is en cs en ru en fy en en is pt is is is en es nl sk it nl sv nl pl is is is es en hbs_lat en ceb is en en en en en is en en en is is is is is is is is is is en is nb nb en is is is de is cs is es ru es nb is en es es en en is de is en cs la es is is es is is id de is eo et ceb is is nn is is is nb is is is en en en en fr fr fr fr en fr en fr fr is en en is nb nb is de is pt cs la tr is is es is is is is id de eo et ceb is nn is is is is en en en is is en en en en en fr fr fr fr en en fr en fr fr fr fr fr en en fr de de fr en it fr fr en it en en en en en en en en en is en en en en fr fr fr fr en fr en es is hbs_lat is is is hbs_lat et en de hbs_lat is en hbs_lat gl is is is is da en en sv is en de is is en en is es hbs_lat en is et is is hbs_lat fi fi is is fi is is is en en da en ca it it hbs_lat en en en en en es fr fr en en pt de en it it en hbs_lat es en en en ceb hu cs et en jv is nb it es en en sv is tt da la sv en vi en en hu ro en ca it sv is en en hbs_lat nl de sv en en ja nl kn en en en en ca es eo nl it it en en en fr en en hbs_lat en ca en en en en en fr hbs_lat hbs_lat en en nl en hbs_lat en en en hbs_lat en en is fr is hbs_lat en hbs_lat cs en en hbs_lat en en en fr hbs_lat is de it pt en en la fr eo en war nb pl en fr en bn fr it sl cy cs ceb cs nb en es is en en it en en eo es en nb en en en is is is en nb en en is hu is en en ja de is en is en en en en pt en en en en is en en en en en en en en en en en fr is is is sv es tr en is is is en is is is is en en is is is is en is en en en en en en de de en is is war en es et is en lt fr fr en en en fr en en nb is cs is is en en en en en is ceb en en en en en en en en en en en en is is en en fr en en en gl is is ca en is is en is en fi is cs is sv is is is en en en en is ceb hbs_lat is en en es en en cs uz en en sv en en is en en fi is en en fr en en gl is is is is en de is is et en es is en en en en is en en en en en is en en hu en en hbs_lat is is en en en is en is is is es is is is is is en en fr en hbs_lat en en en is en en en en en en cs en en en en en en en en da en en en it cs fr ca la en en en en en en en en en en eo en nl en es en en en en en en en en en it en en en en is en en es en en es en es es en en en en en en da en en en en en en en en en en en en en en en en en eo es en fr en en en en en pt en de mk en es en en en en en en en en en en en en en en en it en en oc en la es en it en en en en en en en en en en en pl en en en en en uk en en fi en fr en en es en it tt en en en en en en en en en en en en en en en en en en en en en en en en en it en en en en en en pt en da en da en fr en en en en en en en en en is en en is
ESOblog - A SINFONI of Exoplanets | ESO Ísland
By continuing to use this website, you are giving consent to our use of cookies.
For more information on how ESO uses data and how you can disable cookies, please view our privacy policy.
ESO, Stjörnustöð Evrópulanda á suðurhveli
Prof. H. van der Laan
Public Visits to the ALMA OSF
Large JPG Zip File (1.9 GB)
Original TIF Zip File (32.9 GB)
Notkun á myndum og myndskeiðum ESO
Subtitles and translations for ESO videos
Usage of ESO Videos and Images
Fríar pantanir fyrir kennara og fjölmiðla
Swiss 1.2-metre Leonhard Euler Telescope
TRAnsiting Planets and PlanetesImals Small Telescope–South
Télescope à Action Rapide pour les Objets Transitoires
ESO 1 metra Schmidt-sjónaukinn
ESO 1,52 metra sjónaukinn
Boller and Chivens Spectrograph
ESO 1 metra sjónaukinn
ESO 0,5 metra sjónaukinn
MarLy 1 metra sjónaukinn
Hollenski 0,9 metra sjónaukinn
Bochum 0,61 metra sjónaukinn
Danski 0,5 metra sjónaukinn
Grand Prisme Objectif sjónaukinn
Svissneski 0,4 metra sjónaukinn
Merseille 0,36 metra sjónaukinn
HIRES (Phase A completed)
MOSAIC (Phase A completed)
Companies working on the ELT
Tíu helstu uppgötvanir ESO
Black Hole at the Centre of our Galaxy
Open House Day 2018
Open House Day 2017
Open House Day 2016
Long Night of Science 2015
Open House Day 2014
Café & Kosmos í München
Open House Day 2013
Registration, Fees and Payment
ESO í 50 ár
Hápunktar í 50 ár
Europe to the Stars
50 years of ESO in Chile
Alþjóðlegt ár stjörnufræðinnar 2009
IMAX® Þrívíddarmyndin Hidden Universe
Open House Day 2011
Open House Day 2009 (German)
Long Night of Science 2007
Open House Day 2006
List of Prize Winners
ESO í 40 ár (1962 - 2002)
EuroScience Open Forum (ESOF)
Total Solar Eclipse 2019
The Comet McNaught 2007
Deep Impact - 04.07.2005
The Venus Transit - 08.11.2004
The Leonids - 17.11.1999
Solar Eclipse at ESO HQ - 11.08.1999
The Leonids - 11.1998
Mars Pathfinder - 1997
Comet Hyakutake - 1997
SL-9 and Jupiter - 1994
Comet Hale Bopp - 1994
Málstofur um miðlun stjarnvísinda
ESO Astronomy Camp 2017
ESO Astronomy Camp 2016
ESO Astronomy Camp 2015
ESO Astronomy Camp 2014
Catch a Star 2013
Catch a Star 2011
Catch a Star 2008
Catch a Star 2007
Catch a Star 2005
Catch a Star 2004
Catch a Star 2003
Catch a Star 2002
Life in the Universe
ESO Science Outreach Network
ESO Outreach Partner Organization
Skráningaform fyrir Outreach Newsletter
Taking the First Picture of a Black Hole
Upplýsingar um miðlun stjarnvísinda
European Astronomy Journalism Prize
Technology Developed by Industries
Novel technologies by ESO
Working with the ELT
Umferð og bílastæði hjá ESO
Local Staff Members (Spanish / English)
How to use this site
×Close Afsakaðu! Þessi síða er ekki til á þínu tungumáli, svo við sýnum upprunalegu útgáfuna í staðinn.
Behind the scenes at ESO: Showing you the road to the stars
A SINFONI of Exoplanets
Astronomer Jens Hoeijmakers on how to peer into the atmospheres of distant worlds
What you’ll discover in this blog post:
What an exoplanet is
How SINFONI has been used to measure the atmosphere of an exoplanet
The next big steps in the field
Exoplanets have fast become a huge research area and astronomers are now trying to study their atmospheres. The possibility of finding an exoplanet with an atmosphere that may be able to support life is incredibly exciting. We spoke to Jens Hoeijmakers, from the Geneva Observatory and the Center for Space Habitability in Bern, Switzerland, to find out more about these distant worlds.
Very Large Telescope Interferometer
Q: Let’s start simple: what is an exoplanet?
A: Since 1995, we have known that many stars other than the Sun have their own “solar systems,” with the majority of stars hosting one or multiple planets. Exoplanetary systems come in all shapes and colours, meaning that they are very diverse. Astronomers have discovered planets ranging from gas giants to smaller, rocky planets. Some planets orbit far away from their star like the gas and ice giants in our Solar System, and some orbit very closely, with surface temperatures greater than 1000°C.
We now know of the existence of thousands of exoplanets, and this has shown that planets may even be more common than stars in our Universe
Q: Why do you think it’s important and exciting to study exoplanets?
A: The discovery of the existence of exoplanets has evolved as a major branch of astronomy in the past two decades. We now know of the existence of thousands of exoplanets, and this has shown that planets may even be more common than stars in our Universe! This ubiquitous presence of planets all around us begs the question of whether it’s possible for extraterrestrial life to exist. This is a major driving force behind the continued search for exoplanets and the detailed study of those that we’ve already discovered. But besides the exciting prospect of discovering life, the exoplanet population also gives us a unique window into understanding our own Solar System and the possible outcomes of the same planet formation processes that have made our Solar System the way that we see it today — essentially, studying exoplanets can help us understand how we got to be here.
This composite image represents the close environment of Beta Pictoris as seen in near-infrared light. A very careful subtraction of the much bright stellar halo reveals this very faint environment. The outer part of the image shows the reflected light on the dust disc, as observed with ADONIS on ESO 3.6-metre telescope. The inner part is the innermost part of the system, as seen with NACO on the Very Large Telescope.
Credit: ESO/A.-M. Lagrange et al.
Q: Your research looked at one exoplanet in particular: Beta Pictoris b. Why did you choose to look at this system?
A: Beta Pictoris b is maybe the most famous directly-imaged exoplanet, meaning that astronomers have managed to actually take a snapshot of the planet rather than infer its existence through its indirect effect on its star, as is most commonly done. Beta Pictoris b orbits a bright star about 70 light-years away from Earth, is in a system about 20 to 25 million years old and has a fairly hot surface, about 1700°C.
Beta Pictoris b is one of the easier (but still challenging) planets to image directly because it’s young and hot enough to be observed at infrared wavelengths. When stars and planets form in a large disk of gas and dust, known as the protoplanetary disk, the material from which the planets form is very hot. This means that newborn planets start off with very high temperatures, and throughout the first tens of millions of years of their lives, they slowly cool down as they radiate this heat away, making these planets visible at infrared wavelengths. This is the class of planets that we can directly image, and Beta Pictoris b is a typical example of such a young planet, which is why we chose to observe it — and, indeed, why it is one of the most famous directly imaged exoplanets.
Q: How did you observe Beta Pictoris b and what were you aiming to find?
A: We used existing data of the planet from the SINFONI spectrograph on ESO’s Very Large Telescope located at the Paranal Observatory in Chile. Our aim was actually to test out the instrument — to investigate to what extent an adaptive-optics-assisted integral field spectrograph like SINFONI can be used to study an exoplanet’s atmosphere.
SINFONI is a special instrument. Not only does it perform the high-contrast imaging necessary to separately image the planet from its brighter host star, but it also simultaneously generates a spectrum of each pixel in that image at a high enough resolution. This allows us to see absorption lines in the spectrum of the planet. These absorption lines are what tell us about the chemicals in the planet's atmosphere, and also about the planet's temperature and other physical parameters. In fact, our new technique relies on the fact that the planet's spectrum has absorption lines that are not present in the star that it orbits. This helps us disentangle the planet from its much brighter star, effectively increasing the contrast on top of the already high-contrast imaging from SINFONI. The instrument was not actually designed to be used in this way, so we’re the first to apply this technique.
The only other instrument in the world that can currently perform this type of research is the OSIRIS spectrograph at the Keck Observatory in Hawaii. It is very similar to SINFONI but is located at a much more northern latitude, meaning that SINFONI and OSIRIS can access complementary parts of the sky.
Molecular maps of carbon dioxide (left) and water (right) around Beta Pictoris. Beta Pictoris b is starkly visible in the lower right side of both maps. The left-side scale is the y-position and the bottom-side scale is the x-position. The scale is in arcseconds.
Yepun, the fourth Unit Telescope of the VLT, is angled at a very low altitude, revealing the cell holding its main mirror and the SINFONI integral-field spectrograph.
Q: So what did you and your team find out?
A: First of all, our analysis of the existing dataset confidently shows the presence of water and carbon monoxide in the atmosphere of Beta Pictoris b. This in itself is not a new result because both species were known (and expected) to be present. However, it is the first time that a high-contrast imaging instrument has been used to directly detect these absorption lines in an exoplanet’s atmosphere, thereby uniquely and robustly confirming their presence.
Q: Did you face any challenges during your research?
A: Our analysis was quite challenging because these observations were experimental. SINFONI is not tuned for these kinds of observations, so when the data was initially taken in 2014, it was quickly deemed too challenging even for the detection of the planet, let alone a measurement of its spectrum. In the case of this dataset, our method is more sensitive to the planet, but we also had to overcome the fact that the instrument is simply not designed to image a very faint planet next to a very bright star. This is why we strongly advocate that future, SINFONI-like instruments (such as the planned HARMONI instrument on ESO’s Extremely Large Telescope) should be outfitted with a coronagraph, which blocks out much of the starlight, making such observations even more powerful.
This composite image shows the movement of Beta Pictoris b around its star, observed by the NACO on the VLT over six years.
I sometimes wonder what other new discoveries or applications of existing facilities are still hiding under our noses right now
Q: What do you personally find most exciting about this research?
A: This is a clear example of using an existing dataset and instrument in a completely new way and finding exciting results. I think that there is no reason why the same analysis and observations couldn’t have been carried out 10 years ago, achieving the same results — and something similar is true for the entire field of exoplanets! The first exoplanets could have been discovered with technology that was already available over a decade earlier if only astronomers had taken the possibility of the existence of hot Jupiters seriously. That’s why I sometimes wonder what other new discoveries or applications of existing facilities are still hiding under our noses right now.
Q: What might this research lead to in the future? And what are the next big steps in the field?
A: The strength of our signal spells good news for the future, when new instruments will come online that are similar to SINFONI but much more powerful in terms of contrast and spectral resolution. For instance, our result came from over two hours of observations with SINFONI, but we calculated that the same result could be obtained using the Extremely Large Telescope in only 90 seconds — for a planet like Beta Pictoris that is five times closer to its host star! In this sense, our result is a clear demonstration of this analysis technique and should encourage ongoing development of these future instruments, especially for making them suitable for the high-contrast imaging of exoplanets.
This artist’s rendering of the E-ELT is based on the detailed construction design for the telescope.
Credit: ESO/L. Calçada/ACe Consortium
Numbers in this article
Number of light years Beta Pictoris b is away from Earth
Number of seconds it would take the ELT to complete the same measurement
Temperature, in degrees Celsius, of the surface of the  planet
Age of the Beta Pictoris system
Find out more about SINFONI
Jens Hoeijmakers is a postdoctoral scientist working at the Geneva Observatory and the Center for Space Habitability in Bern, Switzerland. He did his undergraduate, Masters and PhD education in the exoplanet group led by Ignas Snellen in Leiden, The Netherlands. His main focus is the characterisation of exoplanets’ atmospheres, mostly hot Jupiters, which are still very enigmatic and poorly understood. Besides exoplanets, he likes travelling (being an astronomer has its advantages — though not all trips go to desert mountain tops), as well as cooking, the stock market and science fiction movies.
Science Snapshots showcases quirky or interesting scientific results using ESO telescopes from the larger scientific community. Find more interviews with astronomers and stories about astronomical research at ESO here on the ESOblog.
Segðu okkur þitt álit!
Subscribe to receive news from ESO in your language