A team of scientists discovered an exoplanet that resembles an inflated balloon, not just because it is shaped like one, but because it is filled with helium.

The international team of astronomers, including experts from the University of Geneva, said the unique exoplanet, about the size of Neptune and four times larger than Earth, has an average temperature of 1,022 degrees Fahrenheit.

The discovery of thousands of unique exoplanets orbiting the universe is not a scientific breakthrough anymore. This particular discovery, however, was exciting for the scientific community because this was the first time in 18 years that they were able to observe exactly how helium escapes from one gaseous exoplanet’s atmosphere.

Helium is the second most abundant element in the universe. In 2000, scientists theorized that helium could be the perfect signal from which they could observe and study the atmosphere of exoplanets. It was only this year that they were able to witness how helium behaves.

The study, published in the journal Science on Dec. 6, was able to calculate a numerical simulation for how helium moves and why, from humans’ point of view, this gas became like a tail trailing a star or other cosmic bodies. The numerical simulation was able to track the exact trajectory of helium atoms escaping a cosmic body.

"Helium is blown away from the day side of the planet to its night side at over 10'000 km/h because it is such a light gas, it escapes easily from the attraction of the planet and forms an extended cloud all around it,” Vincent Bourrier, co-author of the study, explained.

As for the unique balloon-like shape of the discovered exoplanet, the study said this could be explained by how the exoplanet was positioned in relation to its star. "We suspected that this proximity with the star could impact the atmosphere of this exoplanet," Romain Allart, first author of the study, said.

The exoplanet was affected by the stellar radiation coming from the star, illuminating how the helium escapes to space.

Since 2000, experts knew that helium was extremely hard to spot from space since they are located in the infrared that previous instruments could no longer detect. For this present study, however, the team of international scientists used a telescope equipped with a new feature, a spectrograph called Carmenes.

Christophe Lovis, another co-author of the study, added that the result of their observation also helped in promoting the appreciation for the Carmenes as an integral tool in scientific studies. With the study, he hoped that more telescopes with Carmenes feature will be deployed in different locations across the world.</s>A helium exoplanet inflated like a balloon, research shows. Credit: Denis Bajram

Astronomers have discovered a distant planet with an abundance of helium in its atmosphere, which has swollen to resemble an inflated balloon.

An international team of researchers, including Jessica Spake and Dr. David Sing from the University of Exeter, have detected the inert gas escaping from the atmosphere of the exoplanet HAT-P-11b—found 124 light years from Earth and in the Cygnus constellation.

The remarkable breakthrough was led by researchers from the University of Geneva, who observed the exoplanet using the spectrograph called Carmenes, installed on the 4-metre telescope at Calar Alto, Spain.

For the first time, the data revealed the speed of helium atoms in the upper atmosphere of the exoplanet, which is equivalent in size to Neptune. The helium is in an extended cloud that is escaping from the planet, just as a helium balloon might escape from a person's hand.

The research team believe that the ground-breaking study could open up new understandings of the extreme atmospheric conditions found around the hottest exoplanets.

The research is published in the leading journal, Science, on December 6 2018.

Jessica Spake, part of Exeter's Physics and Astronomy department said: "This is a really exciting discovery, particularly as helium was only detected in exoplanet atmospheres for the first time earlier this year. The observations show helium being blasted away from the planet by radiation from its host star. Hopefully we can use this new study to learn what types of planets have large envelopes of hydrogen and helium, and how long they can hold the gases in their atmospheres."

Helium was first detected as an unknown yellow spectral line signature in sunlight in 1868. Devon-based astronomer Norman Lockyer was the first to propose this line was due to a new element, and named it after the Greek Titan of the Sun, Helios. It has since been discovered to be one of the main constituents of the planets Jupiter and Saturn in our Solar System.

It is also the second most common element in the universe and was long- predicted to be one of the most readily-detectable gases on giant exoplanets. However, it was only successfully found in an exoplanet atmosphere earlier this year, in a pioneering study also led by Jessica Spake.

For this new study, the research team used the spectrograph, Carmenes, to pull apart the star's light into its component colours, like a rainbow, to reveal the presence of helium. The 'rainbow' data, called a spectrum, also tells us the position and speed of helium atoms in the upper atmosphere of HAT-P-11b, which is 20 times closer to its star than the Earth is from the Sun.

Romain Allart, Ph.D. student at the University of Geneva and first author of the study said: "We suspected that this proximity with the star could impact the atmosphere of this exoplanet. The new observations are so precise that the exoplanet atmosphere is undoubtly inflated by the stellar radiation and escapes to space."

Artist impression video of a WASP-69b with its helium tail orbiting its host star. Credit: Gabriel Perez Diaz (IAC)

These new observations are supported by a state-of-the-art computer simulation, led by Vincent Bourrier, co-author of the study and member of the European project FOUR ACES, used to track the trajectory of helium atoms.

Vincent Bourrier explained: "Helium is blown away from the day side of the planet to its night side at over 10,000 km an hour. Because it is such a light gas, it escapes easily from the attraction of the planet and forms an extended cloud all around it."

It is this phenomenon that makes HAT-P-11b so inflated, like a helium balloon.

The first detection of helium earlier this year, led by University of Exeter researchers, opened a new window to observe the extreme atmospheric conditions reigning in the hottest exoplanets. These new observations from Carmenes demonstrate that such studies, long thought feasible only from space, can be achieved with greater precision from ground-based telescopes equipped with the right kind of instruments.

Explore further Helium detected in exoplanet atmosphere for the first time

More information: R. Allart el al., "Spectrally resolved helium absorption from the extended atmosphere of a warm Neptune-mass exoplanet," Science (2018). Journal information: Science R. Allart el al., "Spectrally resolved helium absorption from the extended atmosphere of a warm Neptune-mass exoplanet,"(2018). science.sciencemag.org/lookup/ … 1126/science.aat5879</s>A newly discovered exoplanet 124 light-years away is just full of hot air, according to a new study.

HAT-P-11b, about the size of Neptune and four times larger than Earth, was found in the Cygnus constellation.

The planet is considered a “warm Neptune,” with an average temperature of 1,022 degrees Fahrenheit. For reference, Neptune is the farthest planet in our solar system from the sun, making it one of the coldest, and its average temperature is negative 353 degrees Fahrenheit.

HAT-P-11b is 20 times closer to its star than Earth is to the sun. Its atmosphere is full of helium, swollen like an inflated balloon. And much like a balloon caught in the wind, helium is escaping from the atmosphere in an extended cloud.

Helium, although rare on Earth, is the second most common element in the universe after hydrogen. It’s present in Jupiter and Saturn and is widely thought to be detectable in the atmospheres of exoplanets. But it was only found in the atmosphere of a gas giant exoplanet called WASP-107b this year. The helium itself was hard to detect because the infrared signature of the element is out of the range for instruments used.

Now, for the first time, scientists were able to have detailed observation of how helium is escaping from this gaseous exoplanet’s atmosphere. The study was published Thursday in the journal Science.

“Helium is blown away from the day side of the planet to its night side at over 10,000 kilometers an hour,” said Vincent Bourrier, study co-author and member of the European Research Council’s Future of Upper Atmospheric Characterisation of Exoplanets with Spectroscopy project. “Because it is such a light gas, it escapes easily from the attraction of the planet and forms an extended cloud all around it.”

What enabled this discovery? A new instrument called Carmenes, which is on the 4-meter ground-based telescope at the observatory of Calar Alto in Andalusia, Spain. Carmenes is a spectrograph, which separates a star’s light into the colors that make it up — not unlike a rainbow. This uncovers the spectrum, a measurement of the number of colors that compose this light.

Though humans can’t see any color beyond red when looking at this resolution with the naked eye, the Hubble Space Telescope’s infrared eye can see hundreds of colors.

Carmenes can pick up more than 100,000 colors within the infrared.

The spectrum allowed scientists to pick out not only helium’s signature but the position and speed of the element’s atoms within HAT-P-11b’s upper atmosphere.

“This is a really exciting discovery, particularly as helium was only detected in exoplanet atmospheres for the first time earlier this year,” Jessica Spake, study author and Ph.D. student in the University of Exeter’s Physics and Astronomy Department, said in a statement. “The observations show helium being blasted away from the planet by radiation from its host star. Hopefully we can use this new study to learn what types of planets have large envelopes of hydrogen and helium, and how long they can hold the gases in their atmospheres.”

Spake also led the first pioneering detection of helium on WASP-107b this year.

So why is Hat-P-11b balloon-like? The planet’s close distance to its star seems to be the main culprit.

“We suspected that this proximity with the star could impact the atmosphere of this exoplanet,” said Romain Allart, first author on the study and Ph.D. student at the University of Geneva. “The new observations are so precise that the exoplanet atmosphere is [undoubtedly] inflated by the stellar radiation and escapes to space.”

The research team believes that this detection, combined with the other one from earlier in the year, will open up a new way to observe the extreme atmospheres of some of the hottest exoplanets — and that these observations can be done using ground-based telescopes outfitted with innovative instruments.

“These are exciting times for the search of atmospheric signatures in exoplanets,” said Christophe Lovis in a statement. Lovis is the study’s co-author and a senior lecturer at the University of Geneva. “This result will enhance the interest of the scientific community for these instruments. Their number and their geographical distribution will allow us to cover the entire sky, in search for evaporating exoplanets.”</s>Although helium is a rare element on Earth, it is ubiquitous in the Universe. It is, after hydrogen, the main component of stars and gaseous giant planets. Despite its abundance, helium was only detected recently in the atmosphere of a gaseous giant by an international team including astronomers from the University of Geneva (UNIGE), Switzerland. The team, this time led by Genevan researchers, has observed in detail and for the first time how this gas escapes from the overheated atmosphere of an exoplanet, literally inflated with helium. The results are published in Science.

Helium is the second most abundant element in the Universe. Predicted since 2000 as one of the best possible tracers of the atmospheres of exoplanets, these planets orbiting around other stars than the Sun, it took astronomers 18 years to actually detect it. It was hard to spot due to the very peculiar observational signature of helium, located in the infrared, out of range for most of the instruments used previously. The discovery occurred earlier this year, thanks to Hubble Space Telescope observations, which proved difficult to interpret. Team members from UNIGE, members of the National Centre for Competence in Research PlanetS, had the idea of pointing another telescope equipped with a brand-new instrument - a spectrograph called Carmenes.

A spectrograph decomposes the light of a star into its component colours, like a rainbow. The "resolution" of a spectrograph is a measure indicating the number of colours that can be revealed. While the human eye cannot distinguish any colour beyond red without an adapted camera, the infrared eye of Hubble is capable of identifying hundreds of colours there. This proved sufficient to identify the coloured signature of helium. The instrument Carmenes, installed on the 4-metre telescope at the observatory of Calar Alto in Andalusia, Spain, is capable to identify more than 100'000 colours in the infrared!

This high spectral resolution allowed the team to observe the position and speed of helium atoms in the upper atmosphere of a gaseous Neptune-size exoplanet, 4 times larger than the Earth. Located in the Cygnus (the Swan) constellation, 124 light-years from home, HAT-P-11b is a "warm Neptune" (a decent 550°C!), twenty times closer to its star than the Earth from the Sun. "We suspected that this proximity with the star could impact the atmosphere of this exoplanet" says Romain Allart, PhD student at UNIGE and first author of the study. "The new observations are so precise that the exoplanet atmosphere is undoubtedly inflated by the stellar radiation and escapes to space", he adds.

These observations are supported by numerical simulation, led by Vincent Bourrier, co-author of the study and member of the European project FOUR ACES*. Thanks to the simulation, it is possible to track the trajectory of helium atoms: "helium is blown away from the day side of the planet to its night side at over 10'000 km/h", Vincent Bourrier explains. "Because it is such a light gas, it escapes easily from the attraction of the planet and forms an extended cloud all around it". This gives HAT-P-11b the shape of a helium-inflated balloon.

This result opens a new window to observe the extreme atmospheric conditions prevailing in the hottest exoplanets. The Carmenes observations demonstrate that such studies, long thought feasible only from space, can be achieved with greater precision by ground-based telescopes equipped with the right kind of instruments. "These are exciting times for the search of atmospheric signatures in exoplanets", says Christophe Lovis, senior lecturer at UNIGE and co-author of the study. In fact, UNIGE astronomers are also heavily involved in the design and exploitation of two new high-resolution infrared spectrographs, similar to Carmenes. One of them, called SPIRou, has just started an observational campaign from Hawaii, while the UNIGE Department of astronomy houses the first tests of the Near Infrared Planet Searcher (NIRPS), which will be installed in Chile at the end of 2019. "This result will enhance the interest of the scientific community for these instruments. Their number and their geographical distribution will allow us to cover the entire sky, in search for evaporating exoplanets", concludes Lovis.

*FOUR ACES, Future of Upper Atmospheric Characterisation of Exoplanets with Spectroscopy, is a project funded by a Consolidator grant of the European Research Council (ERC) under the European Unions's 2020 Research and Innovation Programme (grant agreement n°724427).</s>A distant planet the size of Neptune has been discovered about 124 light years away from Earth by a team of astronomers.

The international research team, led by the University of Geneva, say the planet has an atmosphere filled with helium. This has caused the planet to swell to the shape of a balloon.

The inert gas was detected leaking from the planet’s atmosphere in the same way as ‘a helium balloon might escape from a person’s hand’.

Dr Jessica Spake, from the University of Exeter’s physics and astronomy department, said: ‘This is a really exciting discovery, particularly as helium was only detected in exoplanet atmospheres for the first time earlier this year.

‘The observations show helium being blasted away from the planet by radiation from its host star. Hopefully we can use this new study to learn what types of planets have large envelopes of hydrogen and helium, and how long they can hold the gases in their atmospheres.’

The planet has been named HAT-P-11b and is in the Cygnus constellation. As part of the study, researchers used a spectrograph in Spain to measure how much light the planet blocked from its host star when it passed in front of it.

The instrument then pulled apart the star’s light into its component colours, like a rainbow. As helium absorbs light of a specific wavelength, the researchers detected a large cloud of the gas surrounding the planet blocking out much more light than the planet itself. Computer simulations were used to track the trajectory of the helium atoms.

Vincent Bourrier, who led the computer simulation, said: ‘Helium is blown away from the day side of the planet to its night side at over 10,000kph.

‘Because it is such a light gas, it escapes easily from the attraction of the planet and forms an extended cloud all around it.’

It is this phenomenon that gives it the balloon shape. The planet’s upper atmosphere is 20 times closer to its star than the Earth is from the Sun.

Romain Allart, a University of Geneva PhD student and first author of the study, said: ‘We suspected that this proximity with the star could impact the atmosphere of this exoplanet.

‘The new observations are so precise that the exoplanet atmosphere is undoubtedly inflated by the stellar radiation and escapes to space.’

The research team believe the study could lead to a greater understanding of extreme atmospheric conditions around the hottest exoplanets. Helium was only successfully found in the atmosphere of an exoplanet earlier this year in a study led by University of Exeter researchers.</s>To detect the atmosphere of the giant exoplanet WASP-69b, the scientists used the CARMENES instrument, which is installed on the 3.5-meter telescope of the Calar Alto Observatory (located in Almería, Spain). This spectrograph simultaneously covers the visible wavelength range and the near-infrared at high spectral resolution. This has made it possible to reveal the composition of the atmosphere of this exoplanet and to draw conclusions about the speed of the helium particles that leave the gravitational field of the planet and the length of the tail they produce.

The planet was observed during a transit, when it passed in front of its host star. During this event, the planet and its atmosphere eclipse part of the starlight. "We observed a stronger and longer-lasting dimming of the starlight in a region of the spectrum where helium gas absorbs light," says Lisa Nortmann, a researcher at the IAC and lead author of the article published today in the journal Science. "The longer duration of this absorption allows us to infer the presence of a tail," she adds.

But this is not the only result described in the article. The authors have also analyzed four other planets in a similar way. These are the hot exoplanets HD 189733b and HD 209458b, which have a mass similar to that of Jupiter, the extremely hot giant planet KELT-9b and the warm Neptune-sized exoplanet GJ 436b. The analysis does not show extensive helium exospheres around the last three planets, which defies previous theoretical predictions. The hot Jupiter HD 189733b, on the other hand, does reveal a clear signal of absorbing helium, although here, the helium envelope is more compact and does not form a tail.

The team also investigated the host stars of the five exoplanets using data from the European Space Agency's Multi-Mirror X-Ray Mission (ESA XMM-Newton). They detected helium in the atmospheres of those planets that receive the largest amount of X-ray and extreme ultraviolet radiation from their host stars. "This is a first big step toward finding out how exoplanet atmospheres evolve over time, and what the distribution of masses and radii of the observed population of super-Earth and mini-Neptune planets could result from," says Enric Pallé, IAC researcher and co-author of the publication.

The results of such studies could confirm that extreme radiation from the host star can strip the gaseous envelope of giant planets (similar to Jupiter or Neptune) and turn them into rocky planets with densities similar to Venus or Earth. "In the past, studies of atmospheric escape, like the one we have seen in WASP-69b, were based on space-borne observations of hydrogen in the far ultraviolet, a spectral region of very limited access and strongly affected by interstellar absorption," says Michael Salz, a researcher at the University of Hamburg and first author of a companion publication by the same team, which focuses on the details of the detection in HD 189733b to be published in the journal Astronomy & Astrophysics. "Our results show that helium is a very promising new tracer to study atmospheric escape in exoplanets."

This new line of research will enable the community of researchers specializing in characterization of exoplanet atmospheres to compare the evaporation processes in a large sample of planets and answer questions such as whether planets with ultra-short orbital periods are actually the evaporated nuclei of ancient hot Jupiters.

The CARMENES instrument was developed by a consortium of eleven Spanish and German institutions, including the IAC. It was designed to search for terrestrial type planets in the habitable zone of M-stars, the region around a star where conditions allow the existence of liquid water. The results published today demonstrate the ability of the instrument to contribute significantly to the exoplanet atmosphere research field.

Explore further: Helium detected in exoplanet atmosphere for the first time

More information: L. Nortmann el al., "Ground-based detection of an extended helium atmosphere in the Saturn-mass exoplanet WASP-69b," Science (2018). science.sciencemag.org/lookup/ … 1126/science.aat5348</s>The gas tail is made up of helium particles that escape the planet's atmosphere and streak out into space.

Astronomers studying a famous exoplanet that goes by the name of WASP-69b have stumbled upon a peculiar find. It seems that the massive exoplanet, a gas giant first sighted in 2014, is sporting a comet-like tail composed of helium particles that originated in its own atmosphere, reports Phys.org.

This puzzling discovery was made by scientists from the Instituto de Astrofísica de Canarias (IAC) in the Canary Islands, Spain, who scoped out the planet’s atmosphere with the help of the 3.5-meter telescope stationed at the Calar Alto Observatory in Almeria.

The scientists used the telescope’s CARMENES instrument to take a good look at WASP-69b and found out that the exoplanet is losing helium gas, which is agitated by the radiation coming from its parent star and breaking through the planet’s gravitational field.

In a paper published today in the journal Science, the team argued that this strange occurrence is due to a phenomenon called atmospheric escape, in which gas particles from a planet’s atmosphere leak into outer space. A similar thing is happening to Earth’s atmosphere as well, the Inquisitr recently reported, and an orbital mission is gearing up to launch later this month to study the phenomenon in depth.

According to NASA, WASP-69b weighs slightly more than Jupiter and circles its parent star once every 3.9 days. The IAC team observed the exoplanet while it was passing in front of its star. This passage is also known as transit and normally causes the starlight to dim, which typically leads to new exoplanet discoveries via what astronomers call the transit method.

As expected, WASP-69b blocked the star’s light during transit. While this is nothing out of the ordinary, the revelation came once the team noticed that the starlight was blocked at specific wavelengths of the spectrum associated with helium absorption.

“We observed a stronger and longer-lasting dimming of the starlight in a region of the spectrum where helium gas absorbs light,” said IAC astronomer Lisa Nortmann, who led the research.

Since CARMENES is capable of seeing both visible and near-infrared light simultaneously and at high resolution, the observations enabled the team to determine the composition of the exoplanet’s atmosphere. At the same time, the astronomers were able to infer the speed of the helium particles that were escaping the planet’s gravity and to estimate the length of the gas trail left behind.

The video below, released by IAC earlier today, shows a simulation of WASP-69b in transit around its star, displaying the comet-like tail of helium particles that trail behind it.

The case of WASP-69b was measured up against those of four other exoplanets: two hot Jupiters, HD 189733b and HD 209458b; a hot Neptune called GJ 436b; and the hottest planet ever discovered, the ultrahot Jupiter KELT-9b.

As the Inquisitr previously reported, KELT-9b was found in 2017 and has smoldering surface temperatures of up to 7,800 degrees Fahrenheit. Meanwhile, HD 189733b is the first exoplanet whose transit was sighted in X-rays, notes NASA, whereas HD 209458b is the first alien world whose atmosphere was detected by Earth-bound scientists.

After comparing the transits of all five exoplanets, Nortmann’s team uncovered traces of helium in the atmospheres of the planets most battered by X-rays and extreme ultraviolet radiation coming from their parent stars. However, the analysis showed that only WASP-69b and HD 189733b exhibited “a clear signal of absorbing helium” — although, in the case of HD 189733b, “the helium envelope is more compact and does not form a tail,” explains the IAC.

The findings suggest that it could be possible for highly active stars to strip gas giants, such as Jupiter and Neptune, of their gaseous envelope, turning them into rocky worlds with the same kind of density as Venus or Earth. By extrapolation, it might also be feasible for planets with ultra-short orbital periods, that are nestled very close to their parent stars, to actually be the evaporated nuclei of ancient hot Jupiters.

“In the past, studies of atmospheric escape, like the one we have seen in WASP-69b, were based on space-borne observations of hydrogen in the far ultraviolet, a spectral region of very limited access and strongly affected by interstellar absorption,” said study co-author Michael Salz, a researcher at the University of Hamburg. “Our results show that helium is a very promising new tracer to study atmospheric escape in exoplanets.”

A separate study focusing on the discovery regarding HD 189733b is due for publication in the journal Astronomy & Astrophysics.</s>Within these rainbows of light, or spectra, are the signatures of the elements. Helium's spectral signature is particularly susceptible to absorption by the environment that exists in the gulf between stars. Because of this, the element was only discovered for the first time in the atmosphere of an exoplanet last year by astronomers using the Hubble Space Telescope.
Scientists from the University of Geneva announce that a previously-known Neptune-sized exoplanet, HAT-P-11b, has a slowly-escaping helium atmosphere.