̽��ֱ�� of Cambridge - European Southern Observatory

New instrument to search for signs of life on other planets

Anonymous — Wed, 05 Jun 2024 14:00:00 +0000

̽��ֱ��ANDES instrument will be installed on ESO’s Extremely Large Telescope (ELT), currently under construction in Chile’s Atacama Desert. It will be used to search for signs of life in exoplanets and look for the very first stars. It will also test variations of the fundamental constants of physics and measure the acceleration of the Universe’s expansion.

̽��ֱ�� ̽��ֱ�� of Cambridge is a member institution on the project, which involves scientists from 13 countries. Professor Roberto Maiolino, from Cambridge’s Cavendish Laboratory and Kavli Institute for Cosmology, is ANDES Project Scientist.

Formerly known as HIRES, ANDES is a powerful spectrograph, an instrument which splits light into its component wavelengths so astronomers can determine properties about astronomical objects, such as their chemical compositions. ̽��ֱ��instrument will have a record-high wavelength precision in the visible and near-infrared regions of light and, when working in combination with the powerful mirror system of the ELT, it will pave the way for research spanning multiple areas of astronomy.

“ANDES is an instrument with an enormous potential for groundbreaking scientific discoveries, which can deeply affect our perception of the Universe far beyond the small community of scientists,” said Alessandro Marconi, ANDES Principal Investigator.

ANDES will conduct detailed surveys of the atmospheres of Earth-like exoplanets, allowing astronomers to search extensively for signs of life. It will also be able to analyse chemical elements in faraway objects in the early Universe, making it likely to be the first instrument capable of detecting signatures of Population III stars, the earliest stars born in the Universe.

In addition, astronomers will be able to use ANDES’ data to test if the fundamental constants of physics vary with time and space. Its comprehensive data will also be used to directly measure the acceleration of the Universe’s expansion, one of the most pressing mysteries about the cosmos.

When operations start later this decade, the ELT will be the world’s biggest eye on the sky, marking a new age in ground-based astronomy.

Adapted from an ESO press release.

̽��ֱ��European Southern Observatory (ESO) has signed an agreement for the design and construction of ANDES, the ArmazoNes high Dispersion Echelle Spectrograph.

ESO

Artist's impression of the ANDES instrument

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Inferno world with titanium skies

sc604 — Wed, 13 Sep 2017 17:00:00 +0000

̽��ֱ��planet, WASP-19b, has about the same mass as Jupiter, but is so close to its parent star that it completes an orbit in just 19 hours and its atmosphere is estimated to have a temperature of about 2000 degrees Celsius. Such planets are known as ‘hot Jupiters’.

As WASP-19b passes in front of its parent star, some of the starlight passes through the planet’s atmosphere and leaves subtle molecular fingerprints in the light that eventually reaches Earth. “Detecting these molecules is no simple feat,” said lead author Elyar Sedaghati, an ESO fellow and recent graduate of TU Berlin. “We used an algorithm that explores many millions of spectra spanning a wide range of chemical compositions, temperatures, and cloud or haze properties in order to draw our conclusions.”

Using the FORS2 instrument on the European Southern Observatory’s Very Large Telescope in Chile, the team was able to carefully analyse this light and deduce that the atmosphere contained small amounts of titanium oxide, water and traces of sodium, alongside a strongly scattering global haze.

“Titanium oxide can substantially affect the behaviour of WASP-19b's atmosphere,” said co-author Ryan MacDonald, a PhD student at Cambridge’s Institute of Astronomy. “From altering its temperature structure, to driving strong winds, we are now one step closer to uncovering the nature of this extreme world.”

Titanium oxide (TiO) is rarely seen on Earth, but it in the atmospheres of hot planets like WASP-19b, it can absorb the incoming starlight in the same way that ozone absorbs the incoming sunlight in the Earth’s stratosphere. This causes a temperature inversion in the stratosphere whereby temperature increases with altitude. ̽��ֱ��energy from the absorbed starlight higher up in the atmosphere is released locally and causes the temperature to be higher in the upper atmosphere and lower further down, the opposite of the normal situation.

“TiO has been predicted to exist in hot Jupiters for over a decade but its conclusive detection has proved elusive in the past,” said co-author Dr Nikku Madhusudhan of Cambridge’s Institute of Astronomy, who oversaw the atmospheric analyses. “ ̽��ֱ��clear detection of the molecule is a major observational advancement – it is an exciting time in exoplanetary science.”

̽��ֱ��astronomers collected observations of WASP-19b over a period of more than one year. By measuring the relative variations in the planet’s radius at different wavelengths of light that passed through the exoplanet’s atmosphere and comparing the observations to atmospheric models, they could extrapolate different properties, such as the chemical content, of the exoplanet’s atmosphere.

This new information about the presence of titanium oxide and other metal oxides will allow a deeper understanding of the chemical and physical processes in exoplanetary atmospheres. Looking to the future, once astronomers are able to observe atmospheres of possibly habitable planets, the improved models will give them a much better idea of how to interpret those observations.

“This important discovery is the outcome of a refurbishment of the FORS2 instrument that was done exactly for this purpose,” said co-author Henri Boffin from ESO, who led the refurbishment project. “Since then, FORS2 has become the best instrument to perform this kind of study from the ground.”

Reference:
Elyar Sedaghati et al. “Detection of titanium oxide in the atmosphere of a hot Jupiter.” Nature (2017). DOI: 10.1038/nature23651

Adapted from an ESO press release.

An international team of astronomers has detected titanium oxide in the atmosphere of an exoplanet for the first time. ̽��ֱ��results, reported in the journal Nature, provide unique information about the chemical composition and the temperature and pressure structure of the atmosphere of this unusual and very hot world.

̽��ֱ��clear detection of the molecule is a major observational advancement – it is an exciting time in exoplanetary science.

Nikku Madhusudhan

ESO/M. Kornmesser

An artist's impression showing the exoplanet WASP-19b

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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Newly discovered planets could have water on their surfaces

ps748 — Wed, 22 Feb 2017 13:09:42 +0000

̽��ֱ��team has been using the TRAPPIST–South telescope at the European Southern Observatory’s (ESO) La Silla Observatory, the Very Large Telescope (VLT) at Paranal, the NASA Spitzer Space Telescope as well as two other telescopes supported by the UK’s STFC, the William Herschel Telescope and the Liverpool Telescope. All the planets, labelled TRAPPIST-1b, c, d, e, f, g and h in order of increasing distance from their parent star, have sizes comparable to Earth.

̽��ֱ��astronomers identified the planets thanks to periodic drops in the brightness of the central star. As the planets passed in front of the star, they cast a shadow, events known as transits, from which the team could measure the planet’s orbital periods and calculate their sizes and masses. They found that the inner six planets were comparable in size, mass and temperature to the Earth raising the possibility that they host liquid water on their surface.

With just 8% the mass of the Sun, TRAPPIST-1 is very small in stellar terms, only marginally bigger than the planet Jupiter — and though nearby in the constellation Aquarius, it is invisible visually with anything less than powerful telescopes. Astronomers expected that such dwarf stars might host many Earth-sized planets in tight orbits, making them promising targets in the hunt for extraterrestrial life. TRAPPIST-1 is the first such system to be discovered.

Co-author Dr Amaury Triaud, of the ̽��ֱ�� of Cambridge’s Institute of Astronomy, explains: “Stars like TRAPPIST-1 belong to the most common type of stars that exist within our Galaxy. ̽��ֱ��planets that we found are likely representative of the most common sort of planets in the Universe.

“That the planets are so similar to Earth bodes well for the search for life elsewhere. Planets orbiting ultra-cool dwarfs, like TRAPPIST-1, likely represent the largest habitable real estate in the Milky Way!”

̽��ֱ��seven planets of the TRAPPIST-1 system. Credit: ESO

̽��ֱ��team determined that all the planets in the system were similar in size to Earth and Venus in our Solar System, or slightly smaller. ̽��ֱ��density measurements suggest that at least the innermost six are probably rocky in composition.

̽��ֱ��planetary orbits are not much longer than that of Jupiter’s Galilean moon system, and much smaller than the orbit of Mercury in the Solar System. However, TRAPPIST-1’s small size and low temperature means that the energy input to its planets is similar to that received by the inner planets in our Solar System; TRAPPIST-1c, d and f receive similar energy inputs to Venus, Earth and Mars, respectively.

All seven planets discovered in the system could potentially have liquid water on their surfaces, though their orbital distances make some of them more likely candidates than others. Climate models suggest the innermost planets, TRAPPIST-1b, c and d, are probably too hot to support liquid water, except maybe on a small fraction of their surfaces. ̽��ֱ��orbital distance of the system’s outermost planet, TRAPPIST-1h, is unconfirmed, though it is likely to be too distant and cold to harbour liquid water — assuming no alternative heating processes are occurring. TRAPPIST-1e, f, and g, however, are of more interest for planet-hunting astronomers, as they orbit in the star’s habitable zone and could host oceans of surface water.

These new discoveries make the TRAPPIST-1 system an even more important target in the search for extra-terrestrial life. Team member Didier Queloz, from the ̽��ֱ�� of Cambridge’s Cavendish Laboratory, is excited about the future possibilities: “Thanks to future facilities like ESO’s Extremely Large Telescope, or NASA/ESA’s soon-to-be-launched James Webb Space telescope, we will be capable to measure the structure of the planets’ atmospheres, as well as their chemical composition. We are about to start the remote exploration of terrestrial climates beyond our Solar system.”

̽��ֱ��discovery is described in Nature, which also includes a science fiction short story, written by Laurence Suhner. Amaury Triaud comments: “We were thrilled at the idea of having artists be inspired by our discoveries right away. We hope this helps convey the sense of awe and excitement that we all have within the team about the TRAPPIST-1 system.”

̽��ֱ��star draws its name from the TRAPPIST-South telescope, which made the initial discovery. TRAPPIST is the forerunner of a more ambitious facility called “SPECULOOS” that includes Cambridge as core partner, conducted by researchers of the “Cambridge Centre for Exoplanet Research” in the broad research context related to “Universal Life”. SPECULOOS is currently under construction at ESO’ Observatory of Cerro Paranal. SPECULOOS will survey 10 times more stars for planets, than TRAPPIST could do. We expect to detect dozens of additional terrestrial planets.

Michaël Gillon et al: “Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1” Nature 23rd Feb. 2017

http://www.nature.com/nature/journal/v542/n7642/full/nature21360.html

Link to a science-fiction short story: http://www.nature.com/nature/journal/v542/n7642/full/542512a.html

Cambridge Exoplanet Research Centre: http://exoplanets.phy.cam.ac.uk

For additional information, images, videos, a graphic novel and short stories, visit www.trappist.one

Adapted from a press release by the European Southern Observatory (ESO)

An international team of astronomers has found a system of seven potentially habitable planets orbiting a star 39 light years away three of which could have water on their surfaces raising the possibility they could host life. Using ground and space telescopes, the team identified the planets as they passed in front of the ultracool dwarf star known as TRAPPIST-1. ̽��ֱ��star is around eight per cent of the mass of the Sun and is no bigger than Jupiter.

That the planets are so similar to Earth bodes well for the search for life elsewhere

Amaury Triaud

Seven Earths FinalYT1

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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Astronomers observe most distant oxygen ever

sc604 — Thu, 16 Jun 2016 18:10:00 +0000

Astronomers from Japan, Sweden, the United Kingdom and the European Southern Observatory (ESO) have used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe one of the most distant galaxies known. SXDF-NB1006-2 lies at a redshift of 7.2, meaning that we see it only 700 million years after the Big Bang.

̽��ֱ��team was hoping to find out about the chemical elements present in the galaxy, as they can tell us about the level of star formation, and provide clues about the period in the history of the Universe known as cosmic reionisation. Their results are reported today in the journal Science.

“Seeking heavy elements in the early Universe is an essential approach to explore the star formation activity in that period,” said Akio Inoue of Osaka Sangyo ̽��ֱ��, Japan, the paper’s lead author. “Studying heavy elements also gives us a hint to understand how the galaxies were formed and what caused the cosmic reionisation.”

Click image to enlarge.

In the time before objects formed, the Universe was filled with electrically neutral gas. But when the first objects began to shine, a few hundred million years after the Big Bang, they emitted powerful radiation that started to break up those neutral atoms, ionising the gas. During this phase — known as cosmic reionisation — the whole Universe changed dramatically. But there is much debate about exactly what kind of objects caused the reionisation. Studying the conditions in very distant galaxies can help to answer this question.

Before observing the distant galaxy, the researchers performed computer simulations to predict how easily they could expect to see evidence of ionised oxygen with ALMA. They also considered observations of similar galaxies that are much closer to Earth, and concluded that the oxygen emission should be detectable, even at vast distances.

They then carried out high-sensitivity observations with ALMA and found light from ionised oxygen in SXDF-NB1006-2, making this the most distant unambiguous detection of oxygen ever obtained. It is firm evidence for the presence of oxygen in the early Universe, only 700 million years after the Big Bang.

“Many astronomers have believed that ionised carbon emits the strongest light from very distant galaxies in the far infrared range and tried to detect them in the carbon emission using ALMA,” said co-author Dr Kazuaki Ota from the Kavli Institute for Cosmology at the ̽��ֱ�� of Cambridge. “Most of such attempts have failed. However, this study has solely predicted that ionized oxygen emits the strongest light and even detected it from one of the most distant galaxies known. We believe that oxygen could be used as a powerful probe for very distant galaxies.”

Oxygen in SXDF-NB1006-2 was found to be ten times less abundant than it is in the Sun. “ ̽��ֱ��small abundance is expected because the Universe was still young and had a short history of star formation at that time,” said co-author Naoki Yoshida at the ̽��ֱ�� of Tokyo. “Our simulation actually predicted an abundance ten times smaller than the Sun. But we have another, unexpected, result: a very small amount of dust.”

̽��ֱ��team was unable to detect any emission from carbon in the galaxy, suggesting that this young galaxy contains very little un-ionised hydrogen gas, and also found that it contains only a small amount of dust, which is made up of heavy elements. “Something unusual may be happening in this galaxy,” said Inoue. “I suspect that almost all the gas is highly ionised.”

̽��ֱ��detection of ionised oxygen indicates that many very brilliant stars, several dozen times more massive than the Sun, have formed in the galaxy and are emitting the intense ultraviolet light needed to ionise the oxygen atoms.

̽��ֱ��lack of dust in the galaxy allows the intense ultraviolet light to escape and ionise vast amounts of gas outside the galaxy. “SXDF-NB1006-2 would be a prototype of the light sources responsible for the cosmic reionisation,” said Inoue.

“This is an important step towards understanding what kind of objects caused cosmic reionisation,” explained Yoichi Tamura of the ̽��ֱ�� of Tokyo. “Our next observations with ALMA have already started. Higher resolution observations will allow us to see the distribution and motion of ionised oxygen in the galaxy and provide vital information to help us understand the properties of the galaxy.”

Reference:
Inoue et al. “Detection of an oxygen emission line from a high redshift galaxy in the reionization epoch.” Science (2016). DOI: 10.1126/science.aaf0714

Adapted from a press release by NAOJ/ESO

An international team of astronomers have detected glowing oxygen in a distant galaxy seen just 700 million years after the Big Bang. This is the most distant galaxy in which oxygen has ever been unambiguously detected, and it is most likely being ionised by powerful radiation from young giant stars. This galaxy could be an example of one type of source responsible for cosmic reionisation in the early history of the Universe.

Oxygen could be used as a powerful probe for very distant galaxies.

Kazuaki Ota

NAOJ

Artist’s impression of the distant galaxy SXDF-NB1006-2

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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Three potentially habitable worlds found around nearby ultracool dwarf star

sc604 — Mon, 02 May 2016 19:02:00 +0000

An international team of astronomers has discovered three planets orbiting an ultracool dwarf star just 40 light years from Earth. These worlds have sizes and temperatures similar to those of Venus and Earth and may be the best targets found so far for the search for life outside the Solar System. They are the first planets ever discovered around such a tiny and dim star. ̽��ֱ��results are reported in the journal Nature.

Using the TRAPPIST telescope at the European Southern Observatory’s (ESO) La Silla Observatory in Chile, the astronomers observed the star 2MASS J23062928-0502285, now also known as TRAPPIST-1, and located in the Aquarius constellation. They found that this dim and cool star faded slightly at regular intervals, indicating that several objects were transiting, or passing between the star and the Earth. Detailed analysis showed that three planets with similar sizes to the Earth were present.

TRAPPIST-1 is an ultracool dwarf star — much cooler and redder than the Sun and barely larger than Jupiter. Such stars are very common in the Milky Way and very long-lived, but this is the first time that planets have been found around one of them. Despite being so close to the Earth, this star is too dim and too red to be seen with the naked eye or even with a large amateur telescope.

“ ̽��ֱ��discovery of a planetary system around such a small star opens up a brand new avenue for research,” said Professor Didier Queloz from the ̽��ֱ�� of Cambridge’s Cavendish Laboratory, the paper’s senior author. “Before this discovery it was not at all clear whether such a small star could host an Earth-sized planet. Nobody had seriously studied it, but now that’s likely to change.”

“Systems around these tiny stars are the only places where we can detect life on an Earth-sized exoplanet with our current technology,” said the paper’s lead author Michaël Gillon, from the ̽��ֱ�� of Liège in Belgium. “So if we want to find life elsewhere in the Universe, this is where we should start to look.”

Astronomers will search for signs of life by studying the effect that the atmosphere of a transiting planet has on the light reaching Earth. For Earth-sized planets orbiting stars similar to our Sun this tiny effect is swamped because of the large size ratio between the planet and the star. Only for the case of faint red ultra-cool dwarf stars — like TRAPPIST-1 — is this effect big enough to be detected.

Follow-up observations with larger telescopes have shown that the planets orbiting TRAPPIST-1 have sizes very similar to Earth. Two of the planets complete an orbit of the star in 1.5 days and 2.4 days respectively, and the third planet has a less well determined orbital period in the range of 4.5 to 73 days.

“With such short orbital periods, the planets are between 20 and 100 times closer to their star than the Earth to the Sun,” said Gillon. “ ̽��ֱ��structure of this planetary system is much more similar in scale to the system of Jupiter’s moons than to that of the Solar System.”

Although they orbit very close to their host dwarf star, the inner two planets only receive four and two times, respectively, the amount of radiation received by the Earth, because their star is much fainter than the Sun. That puts them closer to the star than the habitable zone for this system. ̽��ֱ��third, outer, planet’s orbit is not yet well known – it probably receives less radiation than the Earth does, but perhaps still enough to lie within the habitable zone.

̽��ֱ��next generation of giant telescopes, such as NASA’s James Webb Telescope due to launch in 2018, will allow researchers to study the atmospheric composition of these planets and to explore them first for water, and then for traces of biological activity.

“While this is not the first time that planets have been found in the habitable zone of a star, the TRAPPIST-1 system provides humanity with our first opportunity to remotely explore Earth-like environments and empirically determine their suitability for life,” said study co-author Dr Amaury Triaud from Cambridge’s Institute of Astronomy. “Because the system contains many planets, we will even be able to compare the climates of each to one another and to the Earth’s.”

This work opens up a new direction for exoplanet hunting, as around 15% of the stars near to the Sun are ultra-cool dwarf stars, and it also serves to highlight that the search for exoplanets has now entered the realm of potentially habitable cousins of the Earth. ̽��ֱ��TRAPPIST survey is a prototype for a more ambitious project called SPECULOOS that will be installed at ESO’s Paranal Observatory in Chile.

Reference:
Michaël Gillon et al. ‘Temperate Earth-sized planets transiting a nearby ultracool dwarf star.’ Nature (2016). DOI: 10.1038/nature17448

Adapted from an ESO press release.

Three Earth-sized planets have been discovered orbiting a dim and cool star, and may be the best place to search for life beyond the Solar System.

̽��ֱ��discovery of a planetary system around such a small star opens up a brand new avenue for research.

Didier Queloz

ESO/M. Kornmesser

Artist’s impression of the ultracool dwarf star TRAPPIST-1 from the surface of one of its planets.

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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Galactic gas caused by colliding comets suggests mystery ‘shepherd’ exoplanet

fpjl2 — Thu, 06 Mar 2014 19:05:00 +0000

Astronomers exploring the disc of debris around the young star Beta Pictoris have discovered a compact cloud of carbon monoxide located about 8 billion miles (13 billion kilometers) from the star. This concentration of poisonous gas – usually destroyed by starlight – is being constantly replenished by ongoing rapid-fire collisions among a swarm of icy, comet-like bodies.

In fact, to offset the destruction of carbon monoxide (CO) molecules around the star, a large comet must be getting completely destroyed every five minutes, say researchers.

They suggest the comet swarm is most likely frozen debris trapped and concentrated by the gravity of an as-yet-unseen exoplanet.

This mystery ‘shepherd’ exoplanet – so-called for its capacity to corral the swarms of comets through its gravitational pull, like Jupiter in our own solar system – is likely to be about the size of Saturn.

"Detailed dynamical studies are now under way, but at the moment we think this shepherding planet would be around Saturn's mass and positioned near the inner edge of the CO belt," said Mark Wyatt, from Cambridge’s Institute of Astronomy, who proposed the shepherd model – currently the favoured hypothesis because it explains so many puzzling features of the Beta Pictoris disc.

"We think the Beta Pictoris comet swarms formed when the hypothetical planet migrated outward, sweeping icy bodies into resonant orbits."

Paradoxically, the presence of carbon monoxide – so harmful to humans on Earth – could indicate that the Beta Pictoris planetary system may eventually be a good habitat for life. If there is CO in the comets, then there is likely also water ice – meaning that the cometary bombardment this system’s planets are probably undergoing could also be providing them with life-giving water.

̽��ֱ��findings are published today in the journal Science Express.

̽��ֱ��clump was discovered when an international team of astronomers, led by ALMA-based ESO astronomer Bill Dent, along with Wyatt, used the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to map the millimeter-wavelength light from dust and carbon monoxide molecules in the disc surrounding Beta Pictoris, a star located about 63 light-years away and only 20 million years old.

Beta Pictoris is considered one of the best examples of a typical young solar system, and hosts one of the closest and brightest debris discs known – making it an ideal laboratory for studying the early development of planetary systems. ̽��ֱ��latest findings could help us understand what conditions were like during the formation of our own solar system.

Much of the carbon monoxide is concentrated in a single clump located about 8 billion miles (13 billion kilometers) from the star, or nearly three times the distance between the planet Neptune and the sun. ̽��ֱ��total amount of the gas observed exceeds 200 million billion tons – equivalent to about one-sixth the mass of Earth’s oceans, say researchers.

̽��ֱ��presence of all this gas is a clue that something interesting is going on because ultraviolet starlight breaks up CO molecules in about 100 years, much faster than the main cloud can complete a single orbit around the star. “So unless we are observing Beta Pictoris at a very unusual time, then the carbon monoxide we observed must be continuously replenished,” said Bill Dent, ESO astronomer based at ALMA and lead author on the paper.

̽��ֱ��researchers calculate that a large comet must be completely destroyed every five minutes, and only an unusually massive and compact swarm of comets could support such an astonishingly high collision rate.

"Although toxic to us, carbon monoxide is one of many gases found in comets and other icy bodies," said team member Aki Roberge, an astrophysicist at NASA’s Goddard Space Flight Center. "In the rough-and-tumble environment around a young star, these objects frequently collide and generate fragments that release dust, icy grains and stored gases."

Because we view the disc nearly edge-on, the ALMA data cannot determine whether the carbon monoxide belt has a single concentration of gas or two on opposite sides of the star. Further studies of the gas cloud's orbital motion will clarify the situation, but current evidence favors a two-clump scenario, which in turn points to a shepherding planet.

In our own solar system, Jupiter's gravity has trapped thousands of asteroids in two groups, one leading and one following it as it travels around the sun. A giant planet located in the outer reaches of the Beta Pictoris system likewise could corral comets into a pair of tight, massive swarms.

Astronomers have already directly imaged one giant exoplanet, Beta Pictoris b, with a mass several times greater than Jupiter, orbiting much closer to the star. While it would be unusual for a giant planet to form up to 10 times farther away, as required to shepherd the massive comet clouds, the hypothetical planet could have formed near the star and migrated outward as the young disc underwent changes. Indeed, this outward motion is needed to corral the comets.

A brief animation expanding on this can be viewed here.

If, however, the gas actually turns out to form a single clump, Wyatt’s recently graduated Cambridge PhD student Alan Jackson, also a co-author on the paper, suggested an even more violent alternative scenario. A crash between two Mars-sized icy planets about half a million years ago would account for the comet swarm, with frequent ongoing collisions among the fragments gradually releasing carbon monoxide gas.

Either way, Beta Pictoris clearly has a fascinating story to tell, say the scientists, one that could provide insight into the early development of our own solar system.

Latest research has uncovered a massive clump of carbon monoxide in a young solar system. ̽��ֱ��gas is the result of near constant collisions of icy comets – suggesting vast swarms of tightly packed comets in thrall to the gravitational pull of an as-yet-unseen exoplanet.

We think the Beta Pictoris comet swarms formed when the hypothetical planet migrated outward

Mark Wyatt

NASA's Goddard Space Flight Center/F.Reddy

At the outer fringes of the system, the gravitational influence of a hypothetical giant planet (bottom left) captures comets into a dense, massive swarm (right) where frequent collisions occur.

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