Lost in space: Rogue planet spotted?

Orphaned world may help to explain how planets and stars form

2012-11-14

(Press-News.org) Astronomers using ESO's Very Large Telescope and the Canada-France-Hawaii Telescope have identified a body that is very probably a planet wandering through space without a parent star. This is the most exciting free-floating planet candidate so far and the closest such object to the Solar System at a distance of about 100 light-years. Its comparative proximity, and the absence of a bright star very close to it, has allowed the team to study its atmosphere in great detail. This object also gives astronomers a preview of the exoplanets that future instruments aim to image around stars other than the Sun.

Free-floating planets are planetary-mass objects that roam through space without any ties to a star. Possible examples of such objects have been found before [1], but without knowing their ages, it was not possible for astronomers to know whether they were really planets or brown dwarfs -- "failed" stars that lack the bulk to trigger the reactions that make stars shine.

But astronomers have now discovered an object, labelled CFBDSIR2149 [2], that seems to be part of a nearby stream of young stars known as the [AB Doradus Moving Group][1]. The researchers found the object in observations from the Canada-France-Hawaii Telescope and harnessed the power of ESO's Very Large Telescope to examine its properties [3].

The AB Doradus Moving Group is the closest such group to the Solar System. Its stars drift through space together and are thought to have formed at the same time. If the object is associated with this moving group -- and hence it is a young object -- it is possible to deduce much more about it, including its temperature, mass, and what its atmosphere is made of [4]. There remains a small probability that the association with the moving group is by chance.

The link between the new object and the moving group is the vital clue that allows astronomers to find the age of the newly discovered object [5]. This is the first isolated planetary mass object ever identified in a moving group, and the association with this group makes it the most interesting free-floating planet candidate identified so far.

"Looking for planets around their stars is akin to studying a firefly sitting one centimetre away from a distant, powerful car headlight," says Philippe Delorme (Institut de planetologie et d'astrophysique de Grenoble, CNRS/Universite Joseph Fourier, France), lead author of the new study. "This nearby free-floating object offered the opportunity to study the firefly in detail without the dazzling lights of the car messing everything up."

Free-floating objects like CFBDSIR2149 are thought to form either as normal planets that have been booted out of their home systems, or as lone objects like the smallest stars or brown dwarfs. In either case these objects are intriguing -- either as planets without stars, or as the tiniest possible objects in a range spanning from the most massive stars to the smallest brown dwarfs.

"These objects are important, as they can either help us understand more about how planets may be ejected from planetary systems, or how very light objects can arise from the star formation process," says Philippe Delorme. "If this little object is a planet that has been ejected from its native system, it conjures up the striking image of orphaned worlds, drifting in the emptiness of space."

These worlds could be common -- perhaps as numerous as normal stars [6]. If CFBDSIR2149 is not associated with the AB Doradus Moving Group it is trickier to be sure of its nature and properties, and it may instead be characterised as a small brown dwarf. Both scenarios represent important questions about how planets and stars form and behave.

"Further work should confirm CFBDSIR2149 as a free-floating planet," concludes Philippe Delorme. "This object could be used as a benchmark for understanding the physics of any similar exoplanets that are discovered by future special high-contrast imaging systems, including the SPHERE instrument that will be installed on the VLT."

INFORMATION:

[1]: http://en.wikipedia.org/wiki/AB_Doradus_moving_group

Notes

[1] Numerous candidates for these kinds of planets have been found before (with corresponding press releases and papers, e.g. from [Science Magazine][1], [Nature][2], [Royal Astronomical Society][3]). These objects started to become known in the 1990s, when astronomers found that the point at which a brown dwarf crosses over into the planetary mass range is difficult to determine. More [recent studies][2] have suggested that there may be huge numbers of these little bodies in our galaxy, a population numbering almost twice as many as the main sequence stars present.

[2] The object was identified as part of an infrared extension of the Canada-France Brown Dwarfs Survey (CFBDS), a project hunting for cool brown dwarf stars. It is also referred to as CFBDSIR J214947.2-040308.9.

[3] The team observed CFBDSIR2149 with both the WIRCam camera on the Canada France Hawaii Telescope on Hawaii, and the SOFI camera on the ESO New Technology Telescope in Chile. The images taken at different times allowed the object's proper motion across the sky to be measured and compared to members of the AB Doradus Moving Group. The detailed study of the object's atmosphere was made using the X-shooter spectrograph on ESO's Very Large Telescope at the Paranal Observatory.

[4] The association with the AB Doradus Moving Group would pin down the mass of the planet to approximately 4-7 times the mass of Jupiter, with an effective temperature of approximately 430 degrees Celsius. The planet's age would be the same as the moving group itself -- 50 to 120 million years.

[5] The team's statistical analysis of the object's proper motion -- its angular change in position across the sky each year -- shows an 87% probability that the object is associated with the AB Doradus Moving Group, and more than 95% probability that it is young enough to be of planetary mass, making it much more likely to be a rogue planet rather than a small "failed" star. More distant free-floating planet candidates have been found before in very young star clusters, but could not be studied in detail.

[6] These free-floating objects can also reveal their presence when they pass in front of a star. The light travelling towards us from the background star is bent and distorted by the gravity of the object, causing the star to suddenly and briefly brighten -- a process known as gravitational microlensing. Microlensing surveys of the Milky Way, such as OGLE, may have detected free-floating planets in this way (for example, a [Microlensing Experiment][2] published in Nature in 2011).

[1]: http://www.sciencemag.org/content/290/5489/103.abstract

[2]: http://www.nature.com/nature/journal/v473/n7347/full/nature10092.html

[3]: http://www.ras.org.uk/news-and-press/71-news2001/405-pn01-12-nam5

More information

This research is presented in a paper, "CFBDSIR2149-0403: a 4-7 Jupiter-mass free-floating planet in the young moving group AB Doradus?" to appear in Astronomy & Astrophysics on 14 November 2012.

The team is composed of P. Delorme (Institut de planetologie et d'astrophysique de Grenoble, CNRS/Universite Joseph Fourier, France [IPAG]), J. Gagne (Universite de Montreal, Canada), L. Malo (Universite de Montreal, Canada), C. Reyle (Universite de Franche Comte, France), E. Artigau (Universite de Montreal, Canada), L. Albert (Universite de Montreal, Canada), T. Forveille (Institut de planetologie et d'astrophysique de Grenoble, CNRS/Universite Joseph Fourier, France [IPAG]), X. Delfosse (Institut de planetologie et d'astrophysique de Grenoble, CNRS/Universite Joseph Fourier, France [IPAG]), F. Allard (Universite Claude Bernard Lyon 1, France), D. Homeier (Universite Claude Bernard Lyon 1, France).

The year 2012 marks the 50th anniversary of the founding of the European Southern Observatory (ESO). ESO is the foremost intergovernmental astronomy organisation in Europe and the world's most productive ground-based astronomical observatory by far. It is supported by 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world's largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning the 39-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".

The Canada-France-Hawaii Telescope (CFHT) is operated by the National Research Council of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.

Links

[Research paper][1] [Photos of the VLT][2] [More information about SPHERE][3]

[1]: http://www.eso.org/public/archives/releases/sciencepapers/eso1245/eso1245a.pdf

[2]: http://www.eso.org/public/images/archive/category/paranal/

[3]: http://www.eso.org/sci/facilities/develop/instruments/sphere.html

Contacts

Philippe Delorme
IPAG-OSUG (Observatoire des Sciences de l'Univers de Grenoble)
Grenoble, France
Tel: +33 4 76 51 49 42
Email: philippe.delorme@obs.ujf-grenoble.fr

Jonathan Gagné
Université de Montréal
Montréal, Canada
Tel: +1 514 343 6111 #3219
Email: jonathan.gagne@astro.umontreal.ca

Xavier Delfosse
IPAG-OSUG (Observatoire des Sciences de l'Univers de Grenoble)
Grenoble, France
Tel: +33 4 76 63 55 10
Email: xavier.delfosse@obs.ujf-grenoble.fr

Olivier Hernandez
Université de Montréal
Montréal, Canada
Tel: +1 514 343 6111 #4681
Email: olivier@astro.umontreal.ca

Céline Reylé
Observatoire de Besançon
Besançon , France
Tel: +33 3 81 66 69 01
Email: celine.reyle@obs-besancon.fr

Richard Hook
ESO, La Silla, Paranal, E-ELT & Survey Telescopes Press Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email: rhook@eso.org

Christian Veillet
Canada-France-Hawaii Telescope
Kamuela, Hawaii, USA
Tel: +1 808 938 3905
Email: veillet@cfht.hawaii.edu

[Attachments] See images for this press release:

ELSE PRESS RELEASES FROM THIS DATE:

Astronomers find 'homeless' planet wandering through space

2012-11-14

A planet that is not orbiting a star, effectively making it homeless, has been discovered by a team of University of Montreal (UdeM) researchers working with European colleagues and data provided by the Canada-France-Hawaii Telescope (CFHT) and the European Southern Observatory's Very Large Telescope (VLT). "Although theorists had established the existence of this type of very cold and young planet, one had never been observed until today," said Étienne Artigau, an astrophysicist at UdeM. The absence of a shining star in the vicinity of this planet enabled the team to study ...

Georgia Tech releases cyber threats forecast for 2013

2012-11-14

The year ahead will feature new and increasingly sophisticated means to capture and exploit user data, escalating battles over the control of online information and continuous threats to the U.S. supply chain from global sources. Those were the findings made by the Georgia Tech Information Security Center (GTISC) and the Georgia Tech Research Institute (GTRI) in today's release of the Georgia Tech Emerging Cyber Threats Report for 2013. The report was released at the annual Georgia Tech Cyber Security Summit, a gathering of industry and academic leaders who have distinguished ...

Pancreas stem cell discovery may lead to new diabetes treatments

2012-11-14

Stem cells in the adult pancreas have been identified that can be turned into insulin producing cells, a finding that means people with type 1 diabetes might one day be able to regenerate their own insulin-producing cells. The discovery was made by scientists from the Walter and Eliza Hall Institute and provides further evidence that stem cells don't only occur in the embryo. The ability to produce the hormone insulin is crucial for controlling blood sugar (glucose) levels. In people with type 1 diabetes the body's immune system destroys the insulin-producing beta cells ...

Antibody-coated stents: Indication of disadvantages

2012-11-14

If narrowed or blocked coronary vessels have to be widened or opened, a vascular support (stent) is usually inserted. Drug-coated stents are preferred for patients at high risk of renewed narrowing of vessels (restenosis). However, the use of antibody-coated stents has been increasing in recent years. Current studies provide indications that these new antibody-coated stents more frequently lead to myocardial infarction and make re-operation necessary. This is the conclusion reached in the rapid report of the German Institute for Quality and Efficiency in Health Care (IQWiG), ...

'Missing link' discovered in the defence mechanism of the tuberculosis pathogen

2012-11-14

Brussels, 14 November 2012 – Flemish biologists lead by Joris Messens (VIB / Vrije Universiteit Brussel) have discovered that Mycobacterium tuberculosis – the bacterium that causes tuberculosis – has an ingenious defence mechanism against oxygen. This knowledge is important in the search for a treatment for tuberculosis. 9.4 million people are infected with tuberculosis annually and 1.7 million people die as a result. Joris Messens: "We have discovered how Mycobacterium survives the oxygen stress in our body, namely with the aid of the protein mycoredoxin-1. This opens ...

Triclosan in cosmetics and personal care products can increase allergy risk

2012-11-14

Triclosan - an antibacterial chemical found in toothpaste and other products - can contribute to an increased risk of allergy development in children. This comes from the Norwegian Environment and Childhood Asthma Study, in which the Norwegian Institute of Public Health is involved. Similar results are reported in the USA. Triclosan has been in use for decades, but was recently associated with allergies in children in an American study, the National Health and Nutrition Examination Survey (NHANES). The new Norwegian study found similar associations between allergies ...

New brain gene gives us edge over apes, study suggests

2012-11-14

Scientists have taken a step forward in helping to solve one of life's greatest mysteries – what makes us human? An international team of researchers have discovered a new gene that helps explain how humans evolved evolved from apes. Scientists say the gene – called miR-941 – appears to have played a crucial role in human brain development and may shed light on how we learned to use tools and language. Researchers say it is the first time that a new gene – carried only by humans and not by apes – has been shown to have a specific function within the human body. A ...

Babies born to stressed mothers more likely to be bullied at school

2012-11-14

Children whose mothers were overly stressed during pregnancy are more likely to become victims of bullying at school. New research from the University of Warwick shows stress and mental health problems in pregnant women may affect the developing baby and directly increases the risk of the child being victimised in later life. The study has been published in the Journal of Child Psychology and Psychiatry and is based on 8,829 children from the Avon Longtitudinal Study of Parents and Children (ALSPAC). Professor Dieter Wolke, Professor of Developmental Psychology at ...

Study investigates headshaking in horses

2012-11-14

Headshaking syndrome is when a horse shakes or jerks its head uncontrollably for no apparent reason. There are striking clinical similarities between facial pain syndromes in people, most notably trigeminal neuralgia, and headshaking in horses. Although some progress has been made towards both diagnosing and treating the condition in horses, the pathology of the disease remains unknown and further research is needed. A recent study led by academics from the University of Bristol's School of Veterinary Sciences and the University of Liverpool, evaluated the long-term ...

Enhancing breast cancer detection

2012-11-14

Straightforward imaging with an infrared, thermal, camera for detecting breast cancer early without the discomfort or inconvenience of mammography or biomolecular tests, according to a study to be published in the International Journal of Innovative Computing and Applications. Tiago Borchartt of the Federal Fluminense University in Brazil and colleagues explain how breast thermography has up to now achieved an average sensitivity and specificity or approximately 90 percent for the detection of malignant tissue. The advantages of the technique are that it is painless, ...

Lost in space: Rogue planet spotted?

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: