\n\t\t\t\t\t\t\t\tWebb Cracks Case of Inflated Exoplanet\t\t\t\t\t\t\t<\/h1>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n![\"Illustration](\"https:\/\/science.nasa.gov\/wp-content\/uploads\/2024\/05\/webb-stsci-01hxw214ra06exqh94wbntpa60-2k.jpg?w=1536\")
<\/figure>\n<\/div>\n<\/div>\n<\/div>\n\n\n\nThis artist\u2019s concept shows what the warm Neptune exoplanet WASP-107 b could look like.<\/figcaption><\/div>\n<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nWhy is the warm gas-giant exoplanet WASP-107 b so puffy? Two independent teams of researchers have an answer.<\/p>\n
Data collected using NASA\u2019s James Webb Space Telescope, combined with prior observations from NASA\u2019s Hubble Space Telescope, show surprisingly little methane (CH4<\/sub>) in the planet\u2019s atmosphere, indicating that the interior of WASP-107 b must be significantly hotter and the core much more massive than previously estimated.<\/p>\nThe unexpectedly high temperature is thought to be a result of tidal heating <\/a>caused by the planet\u2019s slightly non-circular orbit, and can explain how WASP-107 b can be so inflated without resorting to extreme theories of how it formed.<\/p>\nThe results, which were made possible by Webb\u2019s extraordinary sensitivity and accompanying ability to measure light passing through exoplanet atmospheres, may explain the puffiness of dozens of low-density exoplanets, helping solve a long-standing mystery in exoplanet science.<\/p>\n
Image: Warm Gas-Giant Exoplanet WASP-107 b (Artist\u2019s Concept)<\/h2>\n\n\n\n![\"Illustration](\"https:\/\/science.nasa.gov\/wp-content\/uploads\/2024\/05\/webb-stsci-01hxw214ra06exqh94wbntpa60-2k.jpg?w=2000\")
<\/a><\/figure>\nThis artist\u2019s concept shows what the warm Neptune exoplanet WASP-107 b could look like based on recent data gathered by NASA\u2019s James Webb Space Telescope along with previous observations from NASA\u2019s Hubble Space Telescope and other observatories. Observations captured by Hubble\u2019s WFC3 (Wide Field Camera 3), Webb\u2019s NIRCam (Near-Infrared Camera), Webb\u2019s NIRSpec (Near-Infrared Spectrograph), and Webb\u2019s MIRI (Mid-Infrared Instrument) suggest that the planet has a relatively large core surrounded by a relatively small mass of hydrogen and helium gas, which has been inflated due to tidal heating of the interior. <\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nThe Problem with WASP-107 b<\/strong><\/h2>\nAt more than three-quarters the volume of Jupiter but less than one-tenth the mass, the \u201cwarm Neptune\u201d exoplanet WASP-107 b is one of the least dense planets known. While puffy planets are not uncommon, most are hotter and more massive, and therefore easier to explain.<\/p>\n
\u201cBased on its radius, mass, age, and assumed internal temperature, we thought WASP-107 b had a very small, rocky core surrounded by a huge mass of hydrogen and helium,\u201d explained Luis Welbanks from Arizona State University (ASU), lead author on a paper published today in Nature<\/em><\/a>. \u201cBut it was hard to understand how such a small core could sweep up so much gas, and then stop short of growing fully into a Jupiter-mass planet.\u201d<\/p>\nIf WASP-107 b instead has more of its mass in the core, the atmosphere should have contracted as the planet cooled over time since it formed. Without a source of heat to re-expand the gas, the planet should be much smaller. Although WASP-107 b has an orbital distance of just 5 million miles (one-seventh the distance between Mercury and the Sun), it doesn\u2019t receive enough energy from its star to be so inflated.<\/p>\n
\u201cWASP-107 b is such an interesting target for Webb because it\u2019s significantly cooler and more Neptune-like in mass than many of the other low-density planets, the hot Jupiters<\/a>, we\u2019ve been studying,\u201d said David Sing from the Johns Hopkins University (JHU), lead author on a parallel study<\/a> also published today in Nature<\/em>. \u201cAs a result, we should be able to detect methane and other molecules that can give us information about its chemistry and internal dynamics that we can\u2019t get from a hotter planet.\u201d<\/p>\nA Wealth of Previously Undetectable Molecules<\/strong><\/h2>\nWASP-107 b\u2019s giant radius, extended atmosphere, and edge-on orbit make it ideal for transmission spectroscopy<\/a>, a method used to identify the various gases in an exoplanet atmosphere based on how they affect starlight.<\/p>\nCombining observations from Webb\u2019s NIRCam (Near-Infrared Camera), Webb\u2019s MIRI (Mid-Infrared Instrument), and Hubble\u2019s WFC3 (Wide Field Camera 3), Welbanks\u2019 team was able to build a broad spectrum of 0.8- to 12.2-micron light<\/a> absorbed by WASP-107 b\u2019s atmosphere. Using Webb\u2019s NIRSpec (Near-Infrared Spectrograph), Sing\u2019s team built an independent spectrum covering 2.7 to 5.2 microns<\/a>.<\/p>\nThe precision of the data makes it possible to not just detect, but actually measure the abundances of a wealth of molecules, including water vapor (H2<\/sub>O), methane (CH4<\/sub>), carbon dioxide (CO2<\/sub>), carbon monoxide (CO), sulfur dioxide (SO2<\/sub>), and ammonia (NH3<\/sub>).\u00a0<\/p>\nImage:Warm Gas-Giant Exoplanet WASP-107 b Transmission Spectrum (Hubble WFC3, Webb NIRCam, and Webb MIRI<\/h2>\n\n\n\n![\"Graphic](\"https:\/\/science.nasa.gov\/wp-content\/uploads\/2024\/05\/webb-stsci-01hy3fax928vhv0pz8xc48rpyt-4k.png?w=2048\")
<\/a><\/figure>\nThis transmission spectrum, captured using NASA\u2019s Hubble and James Webb space telescopes, shows the amounts of different wavelengths (colors) of starlight blocked by the atmosphere of the gas-giant exoplanet WASP-107 b. The spectrum includes light collected over four separate observations using a total of three different instruments: Hubble\u2019s WFC3 (Wide Field Camera 3) Grism Spectrometer in green, Webb\u2019s NIRCam (Near-Infrared Camera) Grism Spectrometer in orange, and Webb\u2019s MIRI (Mid-Infrared Instrument) Low-Resolution Spectrometer in pink. This spectrum shows clear evidence for water (H2O), carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), sulfur dioxide (SO2), and ammonia (NH4) in the planet\u2019s atmosphere, allowing researchers to estimate the interior temperature and mass of the core. <\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nImage:Warm Gas-Giant Exoplanet WASP-107 b (Transmission Spectrum: Webb NIRSpec)<\/h2>\n\n\n\n![\"Graphic](\"https:\/\/science.nasa.gov\/wp-content\/uploads\/2024\/05\/webb-stsci-01hy1grbnvj096rtae0bqkj6vh-4k.png?w=2048\")
<\/a><\/figure>\nThis transmission spectrum, captured using Webb\u2019s NIRSpec (Near-Infrared Spectrograph) Bright Object Spectrometer, shows the amounts of different wavelengths (colors) of near-infrared starlight blocked by the atmosphere of the gas-giant exoplanet WASP-107 b. The spectrum shows clear evidence for water (H2O), carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), and sulfur dioxide (SO2) in the planet\u2019s atmosphere, allowing researchers to estimate the interior temperature and core mass.<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nRoiling Gas, Hot Interior, and Massive Core<\/strong><\/h2>\nBoth spectra show a surprising lack of methane in WASP-107 b\u2019s atmosphere: one-thousandth the amount expected based on its assumed temperature.<\/p>\n
\u201cThis is evidence that hot gas from deep in the planet must be mixing vigorously with the cooler layers higher up,\u201d explained Sing. \u201cMethane is unstable at high temperatures. The fact that we detected so little, even though we did detect other carbon-bearing molecules, tells us that the interior of the planet must be significantly hotter than we thought.\u201d<\/p>\n
A likely source of WASP-107 b\u2019s extra internal energy is tidal heating caused by its slightly elliptical orbit. With the distance between the star and planet changing continuously over the 5.7-day orbit, the gravitational pull is also changing, stretching the planet and heating it up.<\/p>\n
Researchers had previously proposed that tidal heating could be the cause of WASP-107 b\u2019s puffiness, but until the Webb results were in, there was no evidence.<\/p>\n
Once they established that the planet has enough internal heat to thoroughly churn up the atmosphere, the teams realized that the spectra could also provide a new way to estimate the size of the core.<\/p>\n
\u201cIf we know how much energy is in the planet, and we know what proportion of the planet is heavier elements like carbon, nitrogen, oxygen, and sulfur, versus how much is hydrogen and helium, we can calculate how much mass must be in the core,\u201d explained Daniel Thorngren from JHU.<\/p>\n
It turns out that the core is at least twice as massive as originally estimated, which makes more sense in terms of how planets form.<\/p>\n
All together, WASP-107 b is not as mysterious as it once appeared.<\/p>\n
\u201cThe Webb data tells us that planets like WASP-107 b didn\u2019t have to form in some odd way with a super small core and a huge gassy envelope,\u201d explained Mike Line from ASU. \u201cInstead, we can take something more like Neptune, with a lot of rock and not as much gas, just dial up the temperature, and poof it up to look the way it does.\u201d<\/p>\n
The James Webb Space Telescope is the world\u2019s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).<\/em><\/p>\nDownloads<\/h2>\n
Right click the images in this article to open a larger version<\/strong> in a new tab\/window.
Download full resolution images for this article<\/a><\/strong> from the Space Telescope Science Institute.
The research results are published in Nature<\/strong><\/a>.<\/p>\nMedia Contacts<\/h2>\n
Laura\u00a0Betz<\/strong> \u2013 laura.e.betz@nasa.gov<\/a>, Rob Gutro<\/strong> \u2013 rob.gutro@nasa.gov<\/a>
NASA\u2019s Goddard Space Flight Center<\/a>, Greenbelt, Md.<\/p>\nMargaret Carruthers<\/strong>\u00a0mcarruthers@stsci.edu<\/a>, Christine Pulliam<\/strong> \u2013 cpulliam@stsci.edu<\/a>
Space Telescope Science Institute<\/a>, Baltimore, Md.<\/p>\nRelated Information<\/h2>\n
Research Paper:<\/strong> \u201cA high internal heat flux and large core in a warm Neptune exoplanet\u201d<\/a> by L. Welbanks, et al<\/p>\nResearch Paper<\/strong>: \u201cA warm Neptune\u2019s methane reveals core mass and vigorous atmospheric mixing\u201d<\/a> by D. Sing, et al<\/p>\nResearch Paper: <\/strong> \u201cMIRI observation of WASP-107 b: SO2, silicate clouds, but no CH4 detected in a warm Neptune\u201d<\/a> by A. Dyrek, et al<\/p>\nWhat is an Exoplanet?<\/a><\/strong><\/p>\nVIDEO: How do we learn about a planets Atmosphere?<\/a><\/strong><\/p>\nWebb\u2019s Impact on Exoplanet Research<\/a><\/strong><\/p>\nMore Webb News<\/a><\/strong> \u2013 https:\/\/science.nasa.gov\/mission\/webb\/latestnews\/<\/p>\nMore Webb Images<\/a><\/strong> \u2013 https:\/\/science.nasa.gov\/mission\/webb\/multimedia\/images\/<\/p>\nWebb Mission Page<\/a><\/strong> \u2013 https:\/\/science.nasa.gov\/mission\/webb\/<\/p>\nRelated For Kids<\/h2>\n
What is a exoplanet?<\/a><\/strong><\/p>\nWhat is the Webb Telescope?<\/strong><\/a><\/p>\nSpacePlace for Kids<\/strong><\/a><\/p>\nEn Espa\u00f1ol<\/h2>\n
Para Ni\u00f1os<\/strong> : Qu\u00e9 es una exoplaneta?<\/a><\/strong><\/p>\nCiencia de la NASA<\/strong><\/a><\/p>\nNASA en espa\u00f1ol\u00a0<\/strong><\/a><\/p>\nSpace Place\u00a0para ni\u00f1os<\/strong><\/a><\/p>\n\n\n\n\nKeep Exploring<\/div>\nRelated Topics<\/h2>\n<\/div>\n<\/div>\n\n\t\t\t\t\t<\/p>\n\n
<\/figure>\n<\/div>\n<\/div>\n<\/div>\nWhy is the warm gas-giant exoplanet WASP-107 b so puffy? Two independent teams of researchers have an answer.<\/p>\n
Data collected using NASA\u2019s James Webb Space Telescope, combined with prior observations from NASA\u2019s Hubble Space Telescope, show surprisingly little methane (CH4<\/sub>) in the planet\u2019s atmosphere, indicating that the interior of WASP-107 b must be significantly hotter and the core much more massive than previously estimated.<\/p>\n The unexpectedly high temperature is thought to be a result of tidal heating <\/a>caused by the planet\u2019s slightly non-circular orbit, and can explain how WASP-107 b can be so inflated without resorting to extreme theories of how it formed.<\/p>\n The results, which were made possible by Webb\u2019s extraordinary sensitivity and accompanying ability to measure light passing through exoplanet atmospheres, may explain the puffiness of dozens of low-density exoplanets, helping solve a long-standing mystery in exoplanet science.<\/p>\n At more than three-quarters the volume of Jupiter but less than one-tenth the mass, the \u201cwarm Neptune\u201d exoplanet WASP-107 b is one of the least dense planets known. While puffy planets are not uncommon, most are hotter and more massive, and therefore easier to explain.<\/p>\n \u201cBased on its radius, mass, age, and assumed internal temperature, we thought WASP-107 b had a very small, rocky core surrounded by a huge mass of hydrogen and helium,\u201d explained Luis Welbanks from Arizona State University (ASU), lead author on a paper published today in Nature<\/em><\/a>. \u201cBut it was hard to understand how such a small core could sweep up so much gas, and then stop short of growing fully into a Jupiter-mass planet.\u201d<\/p>\n If WASP-107 b instead has more of its mass in the core, the atmosphere should have contracted as the planet cooled over time since it formed. Without a source of heat to re-expand the gas, the planet should be much smaller. Although WASP-107 b has an orbital distance of just 5 million miles (one-seventh the distance between Mercury and the Sun), it doesn\u2019t receive enough energy from its star to be so inflated.<\/p>\n \u201cWASP-107 b is such an interesting target for Webb because it\u2019s significantly cooler and more Neptune-like in mass than many of the other low-density planets, the hot Jupiters<\/a>, we\u2019ve been studying,\u201d said David Sing from the Johns Hopkins University (JHU), lead author on a parallel study<\/a> also published today in Nature<\/em>. \u201cAs a result, we should be able to detect methane and other molecules that can give us information about its chemistry and internal dynamics that we can\u2019t get from a hotter planet.\u201d<\/p>\n WASP-107 b\u2019s giant radius, extended atmosphere, and edge-on orbit make it ideal for transmission spectroscopy<\/a>, a method used to identify the various gases in an exoplanet atmosphere based on how they affect starlight.<\/p>\n Combining observations from Webb\u2019s NIRCam (Near-Infrared Camera), Webb\u2019s MIRI (Mid-Infrared Instrument), and Hubble\u2019s WFC3 (Wide Field Camera 3), Welbanks\u2019 team was able to build a broad spectrum of 0.8- to 12.2-micron light<\/a> absorbed by WASP-107 b\u2019s atmosphere. Using Webb\u2019s NIRSpec (Near-Infrared Spectrograph), Sing\u2019s team built an independent spectrum covering 2.7 to 5.2 microns<\/a>.<\/p>\n The precision of the data makes it possible to not just detect, but actually measure the abundances of a wealth of molecules, including water vapor (H2<\/sub>O), methane (CH4<\/sub>), carbon dioxide (CO2<\/sub>), carbon monoxide (CO), sulfur dioxide (SO2<\/sub>), and ammonia (NH3<\/sub>).\u00a0<\/p>\n Both spectra show a surprising lack of methane in WASP-107 b\u2019s atmosphere: one-thousandth the amount expected based on its assumed temperature.<\/p>\n \u201cThis is evidence that hot gas from deep in the planet must be mixing vigorously with the cooler layers higher up,\u201d explained Sing. \u201cMethane is unstable at high temperatures. The fact that we detected so little, even though we did detect other carbon-bearing molecules, tells us that the interior of the planet must be significantly hotter than we thought.\u201d<\/p>\n A likely source of WASP-107 b\u2019s extra internal energy is tidal heating caused by its slightly elliptical orbit. With the distance between the star and planet changing continuously over the 5.7-day orbit, the gravitational pull is also changing, stretching the planet and heating it up.<\/p>\n Researchers had previously proposed that tidal heating could be the cause of WASP-107 b\u2019s puffiness, but until the Webb results were in, there was no evidence.<\/p>\n Once they established that the planet has enough internal heat to thoroughly churn up the atmosphere, the teams realized that the spectra could also provide a new way to estimate the size of the core.<\/p>\n \u201cIf we know how much energy is in the planet, and we know what proportion of the planet is heavier elements like carbon, nitrogen, oxygen, and sulfur, versus how much is hydrogen and helium, we can calculate how much mass must be in the core,\u201d explained Daniel Thorngren from JHU.<\/p>\n It turns out that the core is at least twice as massive as originally estimated, which makes more sense in terms of how planets form.<\/p>\n All together, WASP-107 b is not as mysterious as it once appeared.<\/p>\n \u201cThe Webb data tells us that planets like WASP-107 b didn\u2019t have to form in some odd way with a super small core and a huge gassy envelope,\u201d explained Mike Line from ASU. \u201cInstead, we can take something more like Neptune, with a lot of rock and not as much gas, just dial up the temperature, and poof it up to look the way it does.\u201d<\/p>\n The James Webb Space Telescope is the world\u2019s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).<\/em><\/p>\n Right click the images in this article to open a larger version<\/strong> in a new tab\/window. Laura\u00a0Betz<\/strong> \u2013 laura.e.betz@nasa.gov<\/a>, Rob Gutro<\/strong> \u2013 rob.gutro@nasa.gov<\/a> Margaret Carruthers<\/strong>\u00a0mcarruthers@stsci.edu<\/a>, Christine Pulliam<\/strong> \u2013 cpulliam@stsci.edu<\/a> Research Paper:<\/strong> \u201cA high internal heat flux and large core in a warm Neptune exoplanet\u201d<\/a> by L. Welbanks, et al<\/p>\n Research Paper<\/strong>: \u201cA warm Neptune\u2019s methane reveals core mass and vigorous atmospheric mixing\u201d<\/a> by D. Sing, et al<\/p>\n Research Paper: <\/strong> \u201cMIRI observation of WASP-107 b: SO2, silicate clouds, but no CH4 detected in a warm Neptune\u201d<\/a> by A. Dyrek, et al<\/p>\n What is an Exoplanet?<\/a><\/strong><\/p>\n VIDEO: How do we learn about a planets Atmosphere?<\/a><\/strong><\/p>\n Webb\u2019s Impact on Exoplanet Research<\/a><\/strong><\/p>\n More Webb News<\/a><\/strong> \u2013 https:\/\/science.nasa.gov\/mission\/webb\/latestnews\/<\/p>\n More Webb Images<\/a><\/strong> \u2013 https:\/\/science.nasa.gov\/mission\/webb\/multimedia\/images\/<\/p>\n Webb Mission Page<\/a><\/strong> \u2013 https:\/\/science.nasa.gov\/mission\/webb\/<\/p>\n What is a exoplanet?<\/a><\/strong><\/p>\n What is the Webb Telescope?<\/strong><\/a><\/p>\n SpacePlace for Kids<\/strong><\/a><\/p>\n Para Ni\u00f1os<\/strong> : Qu\u00e9 es una exoplaneta?<\/a><\/strong><\/p>\n Ciencia de la NASA<\/strong><\/a><\/p>\n NASA en espa\u00f1ol\u00a0<\/strong><\/a><\/p>\n Space Place\u00a0para ni\u00f1os<\/strong><\/a><\/p>\nImage: Warm Gas-Giant Exoplanet WASP-107 b (Artist\u2019s Concept)<\/h2>\n
<\/a><\/figure>The Problem with WASP-107 b<\/strong><\/h2>\n
A Wealth of Previously Undetectable Molecules<\/strong><\/h2>\n
Image:Warm Gas-Giant Exoplanet WASP-107 b Transmission Spectrum (Hubble WFC3, Webb NIRCam, and Webb MIRI<\/h2>\n
<\/a><\/figure>Image:Warm Gas-Giant Exoplanet WASP-107 b (Transmission Spectrum: Webb NIRSpec)<\/h2>\n
<\/a><\/figure>Roiling Gas, Hot Interior, and Massive Core<\/strong><\/h2>\n
Downloads<\/h2>\n
Download full resolution images for this article<\/a><\/strong> from the Space Telescope Science Institute.
The research results are published in Nature<\/strong><\/a>.<\/p>\nMedia Contacts<\/h2>\n
NASA\u2019s Goddard Space Flight Center<\/a>, Greenbelt, Md.<\/p>\n
Space Telescope Science Institute<\/a>, Baltimore, Md.<\/p>\nRelated Information<\/h2>\n
Related For Kids<\/h2>\n
En Espa\u00f1ol<\/h2>\n
Related Topics<\/h2>\n<\/div>\n<\/div>\n