Image Archive: Exoplanets

WASP 121-b (artist’s impression)

Thu, 04 Jan 2024 16:00:00 +0100

This is an artist’s impression of the exoplanet WASP 121-b, also known as Tylos. The exoplanet’s appearance is based on Hubble data of the object. Using Hubble observations, another team of scientists had previously reported the detection of heavy metals such as magnesium and iron escaping from the upper atmosphere of the ultra-hot Jupiter exoplanet, marking it as the first of such detection. The exoplanet is orbiting dangerously close to its host star, roughly 2.6% of the distance between Earth and the Sun, placing it on the verge of being ripped apart by its host star's tidal forces. The powerful gravitational forces have altered the planet's shape.

An international team of astronomers assembled and reprocessed Hubble observations of the exoplanet made in the years 2016, 2018 and 2019. This provided them with a unique dataset that allowed them not only to analyse the atmosphere of WASP 121-b, but also to compare the state of the exoplanet’s atmosphere across several years. They found clear evidence that the observations of WASP-121 b were varying in time. The team then used sophisticated modelling techniques to demonstrate that these temporal variations could be explained by weather patterns in the exoplanet's atmosphere.

[Image description: An artist impression depicting the exoplanet WASP 121-b. The planet dominates the foreground in the right side of the image, and appears banded with colours of red, yellow and orange. Behind the planet is a large star that appears similar in size to the exoplanet.]

Hubble Finds a Planet Forming in an Unconventional Way

Mon, 04 Apr 2022 17:00:00 +0200

The NASA/ESA Hubble Space Telescope has directly photographed evidence of a Jupiter-like protoplanet forming through what researchers describe as an "intense and violent process." This discovery supports a long-debated theory for how planets like Jupiter form, called "disk instability."

The new world under construction is embedded in a protoplanetary disk of dust and gas with distinct spiral structure swirling around surrounding a young star that’s estimated to be around 2 million years old. That's about the age of our solar system when planet formation was underway. (The solar system's age is currently 4.6 billion years.)

Researchers were able to directly image newly forming exoplanet AB Aurigae b over a 13-year span using the Hubble Space Telescope Imaging Spectrograph (STIS) and its Near Infrared Camera and Multi-Object Spectrograph (NICMOS).

In the top right, Hubble’s NICMOS image captured in 2007 shows AB Aurigae b in a due south position compared to its host star, which is covered by the instrument’s coronagraph. The image captured in 2021 by STIS shows the protoplanet has moved in a counterclockwise motion over time.

Word Bank: Exoplanet

Mon, 02 Aug 2021 14:34:27 +0200

Wide-Field View of GJ 1132 b’s Host Star

Thu, 11 Mar 2021 15:00:00 +0100

Pictured here is the region around the host star of the exoplanet GJ 1132 b.

Artist’s Impression of GJ 1132 b

Thu, 11 Mar 2021 15:00:00 +0100

This image is an artist’s impression of the exoplanet GJ 1132 b.

For the first time, scientists using the NASA/ESA Hubble Space Telescope have found evidence of volcanic activity reforming the atmosphere on this rocky planet, which has a similar density, size, and age to that of Earth.

To the surprise of astronomers, new observations from Hubble have uncovered a second atmosphere that has replaced the planet’s first atmosphere. It is rich in hydrogen, hydrogen cyanide, methane and ammonia, and also has a hydrocarbon haze. Astronomers theorise that hydrogen from the original atmosphere was absorbed into the planet’s molten magma mantle and is now being slowly released by volcanism to form a new atmosphere. This second atmosphere, which continues to leak away into space, is continually being replenished from the reservoir of hydrogen in the mantle’s magma.

GJ 1132 b’s Spectrum

Thu, 11 Mar 2021 15:00:00 +0100

This plot shows the spectrum of the atmosphere of an Earth sized rocky exoplanet, GJ 1132 b, which is overlaid on an artist's impression of the planet.

The orange line represents the model spectrum. In comparison, the observed spectrum is shown as blue dots representing averaged data points, along with their error bars.

This analysis is consistent with GJ 1132 b being predominantly a hydrogen atmosphere with a mix of methane and hydrogen cyanide. The planet also has aerosols which cause scattering of light.

This is the first time a so-called “secondary atmosphere,” which was replenished after the planet lost its primordial atmosphere, has been detected on a world outside of our solar system.

Artist’s Impression of the Hypothesized “Planet Nine”

Thu, 10 Dec 2020 17:00:00 +0100

An 11-Jupiter-mass exoplanet called HD106906 b occupies an unlikely orbit around a double star 336 light-years away and may be offering clues to something that might be much closer to home: a hypothesized distant member of our Solar System dubbed “Planet Nine.” This is the first time that astronomers have been able to measure the motion of a massive Jupiter-like planet that is orbiting very far away from its host stars and visible debris disc.

Region of the Sky Around HD 106906b

Thu, 10 Dec 2020 17:00:00 +0100

Pictured here is the region surrounding the exoplanet HD106906b. Located nearly 336 light-years from Earth, this 11-Jupiter-mass planet occupies an unlikely orbit around a double star 336 light-years away and may be offering clues to something that might be much closer to home: a hypothesized distant member of our Solar System dubbed “Planet Nine.”

This view was created from images forming part of the Digitized Sky Survey 2.

Hubble Probes Exoplanet WASP-79b (Artist’s Impression)

Tue, 05 May 2020 09:50:05 +0200

The NASA/ESA Hubble Space Telescope’s data was used to analyze the atmosphere of the super-hot exoplanet WASP-79b, located 780 light-years away in the constellation Eridanus. Among exoplanets, WASP-79b is among the largest ever observed. The planet is larger than Jupiter, and its very deep, hazy atmosphere sizzles at 1,650 degrees Celsius – the temperature of molten glass. The Hubble Space Telescope and other observatories measured how starlight is filtered through the planet's atmosphere, allowing for its chemical composition to be analyzed. Hubble has detected the presence of water vapor.

The surprise in recently published results, is that the planet's sky doesn't have any evidence for an atmospheric phenomenon called Rayleigh scattering, where certain colors of light are dispersed by very fine dust particles in the upper atmosphere. Rayleigh scattering is what makes Earth's skies blue by scattering the shorter (bluer) wavelengths of sunlight.

Because WASP-79b doesn't seem to have this phenomenon, the daytime sky would likely be yellowish, researchers say.

Link:

NASA Press Release

Visualisation of Fomalhaut and Fomalhaut b (Artist’s Impression)

Mon, 20 Apr 2020 21:00:00 +0200

Data from the NASA/ESA Hubble Space Telescope have revealed an expanding cloud of dust produced in a collision between two large bodies orbiting the bright nearby star Fomalhaut. This is the first time such a catastrophic event around another star has been imaged.

Illustration of Hubble’s Observation of Fomalhaut b’s Expanding Dust Cloud

Mon, 20 Apr 2020 21:00:00 +0200

Illustration from the Hubble Space Telescope’s observations of Fomalhaut b’s expanding dust cloud from 2004 to 2013. The cloud was produced in a collision between two large bodies orbiting the bright nearby star Fomalhaut. This is the first time such a catastrophic event around another star has been imaged.

Hubble Probes Cotton Candy Planets

Mon, 23 Dec 2019 11:43:51 +0100

New observations from the NASA/ESA Hubble Space Telescope have provided the first spectroscopic observations of two of these super-puffy planets, which are located in the Kepler-51 system.

The recent Hubble observations allowed a team of astronomers to refine the mass and size estimates for these worlds – independently confirming their “puffy” nature. Though no more than several times the mass of Earth, their hydrogen/helium atmospheres are so bloated they are nearly the size of Jupiter. In other words, these planets might look as big and bulky as Jupiter, but are roughly 1/100th the mass of Jupiter.

How and why their atmospheres balloon outwards remains unknown, but this feature makes super-puffs prime targets for atmospheric investigation. Using Hubble, the team went looking for evidence of components, notably water, in the atmospheres of Kepler-51b and 51d. Hubble observed the planets when they passed in front of their star, aiming to observe the infrared color of their sunsets. Astronomers deduced the amount of light absorbed by the atmosphere across a range of infrared light wavelengths, thus creating a spectrum for each planet in hopes of seeing the telltale signs of constituents like water in the features of the spectra.

The team concluded that the low densities of these planets are in part a consequence of the young age of the system, a mere 500 million years old. Models suggest these planets formed outside of the star’s “snow line” where icy materials can survive. The planets then migrated inward, like a string of railroad cars.

Link:

NASA Press Release

Exoplanet K2-18b (Artist’s Impression)

Wed, 11 Sep 2019 19:00:00 +0200

This artist’s impression shows the planet K2-18b, it’s host star and an accompanying planet in this system. K2-18b is now the only super-Earth exoplanet known to host both water and temperatures that could support life.

UCL researchers used archive data from 2016 and 2017 captured by the NASA/ESA Hubble Space Telescope and developed open-source algorithms to analyse the starlight filtered through K2-18b’s atmosphere. The results revealed the molecular signature of water vapour, also indicating the presence of hydrogen and helium in the planet’s atmosphere.

Artist’s Impression of WASP-121b

Fri, 02 Aug 2019 10:03:10 +0200

This artist's illustration shows an alien world that is losing magnesium and iron gas from its atmosphere. The observations represent the first time that so-called "heavy metals" — elements more massive than hydrogen and helium — have been detected escaping from a hot Jupiter, a large gaseous exoplanet orbiting very close to its star.

The planet, known as WASP-121b, orbits a star brighter and hotter than the Sun. The planet is so dangerously close to its star that its upper atmosphere reaches a blazing 4,600 degrees Fahrenheit, about 10 times greater than any known planetary atmosphere. A torrent of ultraviolet light from the host star is heating the planet's upper atmosphere, which is causing the magnesium and iron gas to escape into space. Observations by Hubble's Space Telescope Imaging Spectrograph have detected the spectral signatures of magnesium and iron far away from the planet.

The planet's "hugging" distance from the star means that it is on the verge of being ripped apart by the star's gravitational tidal forces. The powerful gravitational forces have altered the planet's shape so that it appears more football shaped.

The WASP-121 system is about 900 light-years from Earth.

Structure of Exoplanet GJ 3470 b

Wed, 03 Jul 2019 15:17:31 +0200

This artist's illustration shows the theoretical internal structure of the exoplanet GJ 3470 b. It is unlike any planet found in the Solar System. Weighing in at 12.6 Earth masses the planet is more massive than Earth but less massive than Neptune. Unlike Neptune, which is 3 billion miles from the Sun, GJ 3470 b may have formed very close to its red dwarf star as a dry, rocky object. It then gravitationally pulled in hydrogen and helium gas from a circumstellar disk to build up a thick atmosphere. The disk dissipated many billions of years ago, and the planet stopped growing. The bottom illustration shows the disk as the system may have looked long ago. Observations by the NASA/ESA Hubble Space telescope and the NASA Spitzer space telescopes have chemically analyzed the composition of GJ 3470 b's very clear and deep atmosphere, yielding clues to the planet's origin. Many planets of this mass exist in our galaxy.

Link:

NASA Press Release

Exoplanet radius versus distance from star

Mon, 17 Dec 2018 15:51:43 +0100

This graphic plots exoplanets based on their size and distance from their star. Each dot represents an exoplanet. Planets the size of Jupiter (located at the top of the graphic) and planets the size of Earth and so-called super-Earths (at the bottom) are found both close to and far from their star. But planets the size of Neptune (in the middle of the plot) are scarce close to their star. This so-called desert of hot Neptunes shows that such alien worlds are rare, or, they were plentiful at one time, but have since disappeared. The detection that GJ 3470b, a warm Neptune at the border of the desert, is fast losing its atmosphere suggests that hotter Neptunes may have eroded down to smaller, rocky super-Earths.

Artist's impression of gas streaming from GJ 3470b

Mon, 17 Dec 2018 15:51:27 +0100

This artist's impression shows a giant cloud of hydrogen streaming off a warm, Neptune-sized planet just 97 light-years from Earth. The exoplanet is tiny compared to its star, a red dwarf named GJ 3470. The star's intense radiation is heating the hydrogen in the planet's upper atmosphere to a point where it escapes into space. The alien world is losing hydrogen at a rate 100 times faster than a previously observed warm Neptune whose atmosphere is also evaporating away.

Exomoon orbiting its planet (artist’s impression)

Wed, 03 Oct 2018 20:00:00 +0200

This artist’s impression depicts the exomoon candidate Kepler-1625b-i, the planet it is orbiting and the star in the centre of the star system. Kepler-1625b-i is the first exomoon candidate and, if confirmed, the first moon to be found outside the Solar System.

Like many exoplanets, Kepler-1625b-i was discovered using the transit method. Exomoons are difficult to find because they are smaller than their companion planets, so their transit signal is weak, and their position in the system changes with each transit because of their orbit. This requires extensive modelling and data analysis.

Artist’s impression of WASP-107b

Wed, 02 May 2018 19:00:00 +0200

The exoplanet WASP-107b is a gas giant, orbiting a highly active K-type main sequence star. The star is about 200 light-years from Earth. Using spectroscopy, scientists were able to find helium in the escaping atmosphere of the planet — the first detection of this element in the atmosphere of an exoplanet.

Huge system of dusty material enveloping the young star HR 4796A

Fri, 09 Mar 2018 13:58:48 +0100

This is an image from the NASA/ESA Hubble Space Telescope showing a vast, complex dust structure, about 240 billion kilometres across, enveloping the young star HR 4796A. A bright, narrow inner ring of dust is already known to encircle the star and may have been corralled by the gravitational pull of an unseen giant planet. This newly discovered huge dust structure around the system may have implications for what this yet-unseen planetary system looks like around the 8-million-year-old star, which is in its formative years of planet construction. The debris field of very fine dust was likely created from collisions among developing infant planets near the star, evidenced by a bright ring of dusty debris seen 11 billion kilometres from the star. The pressure of starlight from the star, which is 23 times more luminous than the Sun, then expelled the dust far into space.

Link:

NASA press release

Wasp-39b and its parent star (artist’s impression)

Thu, 01 Mar 2018 19:00:00 +0100

A team of British and American astronomers used data from several telescopes on the ground and in space — among them the NASA/ESA Hubble Space Telescope — to study the atmosphere of the hot, bloated, Saturn-mass exoplanet WASP-39b, about 700 light-years from Earth. The analysis of the spectrum showed a large amount of water in the exoplanet’s atmosphere — three times more than in Saturn’s atmosphere.

WASP-39b is eight times closer to its parent star, WASP-39, than Mercury is to the Sun and it takes only four days to complete an orbit.

Comprehensive Spectrum of WASP-39b

Thu, 01 Mar 2018 19:00:00 +0100

Using the NASA/ESA Hubble Space Telescopes as well as data gathered by other telescopes in space and on the ground astronomers have analysed the atmosphere of the exoplanet WASP-39b. It is the most complete spectrum of an exoplanet’s atmosphere possible with present-day technology.

By dissecting starlight filtering through the planet’s atmosphere into its component colours, the team found clear evidence for water vapour. Although the researchers predicted they would see water, they were surprised by how much water they found — three times as much as Saturn has. This suggests that the planet formed farther out from the star, where it was bombarded by icy material.

The habitable zone in the TRAPPIST-1 system

Mon, 05 Feb 2018 17:00:00 +0100

The TRAPPIST-1 system contains a total of seven known Earth-sized planets. Three of them — TRAPPIST-1e, f and g — are located in the habitable zone of the star (shown in green in this artist’s impression), where temperatures are just right for liquid water to exist on the surface.

While TRAPPIST-1b, c and d are too close to their parent star and TRAPPIST-1h is too far away, the remaining three planets could have the right conditions to harbour life.

As a comparison to the TRAPPIST-1 system the inner part of the Solar System and its habitable zone is shown.

Artist's illustrations of planets in TRAPPIST-1 system and Solar System rocky planets

Mon, 05 Feb 2018 17:00:00 +0100

This infographic displays some artist's illustrations of how the seven planets orbiting TRAPPIST-1 might appear — including the possible presence of water oceans — alongside some images of the rocky planets in our Solar System. Information about the size and orbital periods of all the planets is also provided for comparison; the TRAPPIST-1 planets are all approximately Earth-sized.

Spectra of planets in TRAPPIST-1 system

Mon, 05 Feb 2018 17:00:00 +0100

These spectra show the chemical makeup of the atmospheres of four of the Earth-sized planets orbiting within or near the habitable zone of the star TRAPPIST-1.

To obtain the spectra, astronomers used the NASA/ESA Hubble Space Telescope to collect light from TRAPPIST-1 passing through the exoplanets’ atmospheres as the exoplanets crossed in front of the star.

The purple curves show the predicted signatures of gases such as water and methane that absorb certain wavelengths of light. These gases would be found in a puffy hydrogen-dominated atmosphere similar to those of gaseous planets such as Neptune. The Hubble results, indicated by the green crosses, reveal no evidence of an extended atmosphere in three of the exoplanets (TRAPPIST-1d, f, and e). Additional observations are needed to rule out a hydrogen-dominated atmosphere for the fourth planet (TRAPPIST-1g).

The evidence indicates that the atmospheres are more compact than could be measured by the Hubble observations.

Image Archive: Exoplanets

WASP 121-b (artist’s impression)

Hubble Finds a Planet Forming in an Unconventional Way

Word Bank: Exoplanet

Wide-Field View of GJ 1132 b’s Host Star

Artist’s Impression of GJ 1132 b

GJ 1132 b’s Spectrum

Artist’s Impression of the Hypothesized “Planet Nine”

Region of the Sky Around HD 106906b

Hubble Probes Exoplanet WASP-79b (Artist’s Impression)

Visualisation of Fomalhaut and Fomalhaut b (Artist’s Impression)

Illustration of Hubble’s Observation of Fomalhaut b’s Expanding Dust Cloud

Hubble Probes Cotton Candy Planets

Exoplanet K2-18b (Artist’s Impression)

Artist’s Impression of WASP-121b

Structure of Exoplanet GJ 3470 b

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Exoplanet radius versus distance from star

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Artist's impression of gas streaming from GJ 3470b

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Exomoon orbiting its planet (artist’s impression)

Artist’s impression of WASP-107b

Huge system of dusty material enveloping the young star HR 4796A

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Wasp-39b and its parent star (artist’s impression)

Comprehensive Spectrum of WASP-39b

The habitable zone in the TRAPPIST-1 system

Artist's illustrations of planets in TRAPPIST-1 system and Solar System rocky planets

Spectra of planets in TRAPPIST-1 system