From European Southern Observatory: “SPHERE Reveals Fascinating Zoo of Discs Around Young Stars”

ESO 50 Large

European Southern Observatory

11 April 2018
Henning Avenhaus
Max Planck Institute for Astronomy
Heidelberg, Germany
Email: havenhaus@gmail.com

Elena Sissa
INAF – Astronomical Observatory of Padova
Padova, Italy
Email: elena.sissa@inaf.it

Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email: rhook@eso.org

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This spectacular image from the SPHERE instrument on ESO’s Very Large Telescope shows the dusty disc around the young star IM Lupi in finer detail than ever before. Credit: ESO/H. Avenhaus et al./DARTT-S collaboration.

New images from the SPHERE instrument on ESO’s Very Large Telescope are revealing the dusty discs surrounding nearby young stars in greater detail than previously achieved. They show a bizarre variety of shapes, sizes and structures, including the likely effects of planets still in the process of forming.

ESO/SPHERE extreme adaptive optics system and coronagraphic facility on the VLT, Cerro Paranal, Chile

ESO SPHERE extreme adaptive optics system and coronagraphic facility on the extreme adaptive optics system and coronagraphic facility on the VLT, Cerro Paranal, Chile, with an elevation of 2,635 metres (8,645 ft) above sea level
ESO SPHERE extreme adaptive optics system and coronagraphic facility on the extreme adaptive optics system and coronagraphic facility on the VLT, Cerro Paranal, Chile, with an elevation of 2,635 metres (8,645 ft) above sea level

The SPHERE instrument on ESO’s Very Large Telescope (VLT) in Chile allows astronomers to suppress the brilliant light of nearby stars in order to obtain a better view of the regions surrounding them. This collection of new SPHERE images is just a sample of the wide variety of dusty discs being found around young stars.

These discs are wildly different in size and shape — some contain bright rings, some dark rings, and some even resemble hamburgers. They also differ dramatically in appearance depending on their orientation in the sky — from circular face-on discs to narrow discs seen almost edge-on.

SPHERE’s primary task is to discover and study giant exoplanets orbiting nearby stars using direct imaging. But the instrument is also one of the best tools in existence to obtain images of the discs around young stars — regions where planets may be forming. Studying such discs is critical to investigating the link between disc properties and the formation and presence of planets.

Many of the young stars shown here come from a new study of T Tauri stars, a class of stars that are very young (less than 10 million years old) and vary in brightness. The discs around these stars contain gas, dust, and planetesimals — the building blocks of planets and the progenitors of planetary systems.

These images also show what our own Solar System may have looked like in the early stages of its formation, more than four billion years ago.

Most of the images presented were obtained as part of the DARTTS-S (Discs ARound T Tauri Stars with SPHERE) survey. The distances of the targets ranged from 230 to 550 light-years away from Earth. For comparison, the Milky Way is roughly 100 000 light-years across, so these stars are, relatively speaking, very close to Earth. But even at this distance, it is very challenging to obtain good images of the faint reflected light from discs, since they are outshone by the dazzling light of their parent stars.

Another new SPHERE observation is the discovery of an edge-on disc around the star GSC 07396-00759, found by the SHINE (SpHere INfrared survey for Exoplanets) survey. This red star is a member of a multiple star system also included in the DARTTS-S sample but, oddly, this new disc appears to be more evolved than the gas-rich disc around the T Tauri star in the same system, although they are the same age. This puzzling difference in the evolutionary timescales of discs around two stars of the same age is another reason why astronomers are keen to find out more about discs and their characteristics.

Astronomers have used SPHERE to obtain many other impressive images, as well as for other studies including the interaction of a planet with a disc, the orbital motions within a system, and the time evolution of a disc.

The new results from SPHERE, along with data from other telescopes such as ALMA, are revolutionising astronomers’ understanding of the environments around young stars and the complex mechanisms of planetary formation.
More information

The images of T Tauri star discs were presented in a paper entitled Disks Around T Tauri Stars With SPHERE (DARTTS-S) I: SPHERE / IRDIS Polarimetric Imaging of 8 Prominent T Tauri Disks, by H. Avenhaus et al., to appear in in the Astrophysical Journal. The discovery of the edge-on disc is reported in a paper entitled A new disk discovered with VLT/SPHERE around the M star GSC 07396-00759</em”, by E. Sissa et al., to appear in the journal Astronomy & Astrophysics.

The first team is composed of Henning Avenhaus (Max Planck Institute for Astronomy, Heidelberg, Germany; ETH Zurich, Institute for Particle Physics and Astrophysics, Zurich, Switzerland; Universidad de Chile, Santiago, Chile), Sascha P. Quanz (ETH Zurich, Institute for Particle Physics and Astrophysics, Zurich, Switzerland; National Center of Competence in Research “PlanetS”), Antonio Garufi (Universidad Autonónoma de Madrid, Madrid, Spain), Sebastian Perez (Universidad de Chile, Santiago, Chile; Millennium Nucleus Protoplanetary Disks Santiago, Chile), Simon Casassus (Universidad de Chile, Santiago, Chile; Millennium Nucleus Protoplanetary Disks Santiago, Chile), Christophe Pinte (Monash University, Clayton, Australia; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France), Gesa H.-M. Bertrang (Universidad de Chile, Santiago, Chile), Claudio Caceres (Universidad Andrés Bello, Santiago, Chile), Myriam Benisty (Unidad Mixta Internacional Franco-Chilena de Astronomía, CNRS/INSU; Universidad de Chile, Santiago, Chile; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France) and Carsten Dominik (Anton Pannekoek Institute for Astronomy, University of Amsterdam, The Netherlands).

The second team is composed of: E. Sissa (INAF-Osservatorio Astronomico di Padova, Padova, Italy), J. Olofsson (Max Planck Institute for Astronomy, Heidelberg, Germany; Universidad de Valparaíso, Valparaíso, Chile), A. Vigan (Aix-Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille, Marseille, France), J.C. Augereau (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France) , V. D’Orazi (INAF-Osservatorio Astronomico di Padova, Padova, Italy), S. Desidera (INAF-Osservatorio Astronomico di Padova, Padova, Italy), R. Gratton (INAF-Osservatorio Astronomico di Padova, Padova, Italy), M. Langlois (Aix-Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille Marseille, France; CRAL, CNRS, Université de Lyon, Ecole Normale Suprieure de Lyon, France), E. Rigliaco (INAF-Osservatorio Astronomico di Padova, Padova, Italy), A. Boccaletti (LESIA, Observatoire de Paris-Meudon, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, Meudon, France), Q. Kral (LESIA, Observatoire de Paris-Meudon, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, Meudon, France; Institute of Astronomy, University of Cambridge, Cambridge, UK), C. Lazzoni (INAF-Osservatorio Astronomico di Padova, Padova, Italy; Universitá di Padova, Padova, Italy), D. Mesa (INAF-Osservatorio Astronomico di Padova, Padova, Italy; University of Atacama, Copiapo, Chile), S. Messina (INAF-Osservatorio Astrofisico di Catania, Catania, Italy), E. Sezestre (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), P. Thébault (LESIA, Observatoire de Paris-Meudon, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, Meudon, France), A. Zurlo (Universidad Diego Portales, Santiago, Chile; Unidad Mixta Internacional Franco-Chilena de Astronomia, CNRS/INSU; Universidad de Chile, Santiago, Chile; INAF-Osservatorio Astronomico di Padova, Padova, Italy), T. Bhowmik (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), M. Bonnefoy (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), G. Chauvin (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France; Universidad Diego Portales, Santiago, Chile), M. Feldt (Max Planck Institute for Astronomy, Heidelberg, Germany), J. Hagelberg (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), A.-M. Lagrange (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), M. Janson (Stockholm University, Stockholm, Sweden; Max Planck Institute for Astronomy, Heidelberg, Germany), A.-L. Maire (Max Planck Institute for Astronomy, Heidelberg, Germany), F. Ménard (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), J. Schlieder (NASA Goddard Space Flight Center, Greenbelt, Maryland, USA; Max Planck Institute for Astronomy, Heidelberg, Germany), T. Schmidt (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), J. Szulági (Institute for Particle Physics and Astrophysics, ETH Zurich, Zurich, Switzerland; Institute for Computational Science, University of Zurich, Zurich, Switzerland), E. Stadler (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), D. Maurel (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), A. Deboulbé (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), P. Feautrier (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), J. Ramos (Max Planck Institute for Astronomy, Heidelberg, Germany) and R. Rigal (Anton Pannekoek Institute for Astronomy, Amsterdam, The Netherlands).

See the full article here .

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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 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. 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 a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

ESO LaSilla
ESO/Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

ESO VLT
VLT at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level.
ESO Vista Telescope

Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

ESO/Vista Telescope at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level.

ESO NTT
ESO/NTT at Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

ESO VLT Survey telescope
VLT Survey Telescope at Cerro Paranal with an elevation of 2,635 metres (8,645 ft) above sea level.

ALMA Array
ALMA on the Chajnantor plateau at 5,000 metres.

ESO E-ELT
ESO/E-ELT to be built at Cerro Armazones at 3,060 m.

ESO APEX
APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert.

Leiden MASCARA instrument, La Silla, located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)
Leiden MASCARA cabinet at ESO Cerro la Silla located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)
ESO Next Generation Transit Survey at Cerro Paranel, 2,635 metres (8,645 ft) above sea level
SPECULOOS four 1m-diameter robotic telescopes 2016 in the ESO Paranal Observatory, 2,635 metres (8,645 ft) above sea level
ESO TAROT telescope at Paranal, 2,635 metres (8,645 ft) above sea level
ESO ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres

From ESO: “ESO’s SPHERE Unveils its First Exoplanet”

ESO 50 Large

European Southern Observatory

6 July 2017
Gaël Chauvin
Institut de Planetologie et d’Astrophysique de Grenoble (IPAG)
BP 53, 38041 Grenoble Cedex 9, France
+33 6 4551 8209
gael.chauvin@univ-grenoble-alpes.fr

Jean-Luc Beuzit
Institut de Planetologie et d’Astrophysique de Grenoble (IPAG)
BP 53, 38041 Grenoble Cedex 9, France
+33 6 8739 6285
jean-luc.beuzit@univ-grenoble-alpes.fr

Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
rhook@eso.org

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One of the most challenging and exciting areas of astronomy today is the search for exoplanets — other worlds orbiting other stars. The exoplanet HIP 65426b has recently been discovered using the SPHERE (Spectro-Polarimetric High-contrast Exoplanet REsearch instrument) instrument on ESO’s Very Large Telescope (VLT). Some 385 light-years from us, HIP 65426b is the first planet that SPHERE has found [1] — and it turns out to be a particularly interesting one.

ESO/VLT at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level
ESO SPHERE extreme adaptive optics system and coronagraphic facility on the extreme adaptive optics system and coronagraphic facility on the VLT, Cerro Paranal, Chile, with an elevation of 2,635 metres (8,645 ft) above sea level

The planet is warm (between 1000 and 1400 degrees Celsius), and is between six and twelve times the mass of Jupiter. It seems to have a very dusty atmosphere filled with thick cloud, and it orbits a hot, young star that rotates surprisingly fast. Unusually, given its age, the star does not appear to be surrounded by a disc of debris, and the absence of a disc raises puzzling questions about how the planet formed in the first place. The planet may have been formed in a disc of gas and dust and when the disc rapidly dissipated, it interacted with other planets to move to a more distant orbit, where we see it now. Alternatively, the star and the planet may have formed together as a binary system in which the more massive component prevented the other would-be star from accumulating sufficient matter to actually become a star. The planet’s discovery gives astronomers the opportunity to study the composition and location of clouds in its atmosphere, and to test theories of the formation, evolution, and physics of exoplanets.

SPHERE is a powerful planet finder installed on Unit Telescope 3 of the VLT. Its science goal is to detect and study new giant exoplanets around nearby stars using the direct imaging method [2]. This method aims to directly capture images of exoplanets and debris discs around stars, rather like taking a photograph. Direct imaging is difficult because the light of a star is so powerful that the feeble light reflected by orbiting planets is overwhelmed by the starlight. But SPHERE is cleverly designed to bypass this obstacle and to look specifically for the polarised light reflected off a planet’s surface.

This image was captured as part of a survey programme called SHINE (SpHere INfrared survey for Exoplanets). SHINE aims to image 600 young nearby stars in the near-infrared using SPHERE’s high contrast and high angular resolution to discover and characterise new planetary systems and explore how they formed.

Notes

[1] A previous ESO press release reported an earlier SPHERE observation that was interpreted as a planet. However, that interpretation has been called into doubt and so HIP 65426b is currently the first reliable detection of an exoplanet by SPHERE.

[2] When scouring the Universe for exoplanets, astronomers have numerous tools at their disposal. Many planet detection methods are indirect — astronomers can detect the tell-tale dip in a star’s brightness when a planet transits across its face, or measure the tiny wobble in a star’s motion caused by the gravitational tug of any orbiting planets.

Planet transit. NASA/Ames

However, there is a more direct method of finding an exoplanet: direct imaging.

See the full article here .

Please help promote STEM in your local schools.
STEM Icon

Stem Education Coalition
Visit ESO in Social Media-

Facebook

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ESO Bloc Icon

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 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. 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 a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

ESO LaSilla
ESO/Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres

ESO VLT
VLT at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level

ESO Vista Telescope
ESO/Vista Telescope at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level

ESO NTT
ESO/NTT at Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres

ESO VLT Survey telescope
VLT Survey Telescope at Cerro Paranal with an elevation of 2,635 metres (8,645 ft) above sea level

ALMA Array
ALMA on the Chajnantor plateau at 5,000 metres

ESO E-ELT
ESO/E-ELT to be built at Cerro Armazones at 3,060 m

ESO APEX
APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert