
Atmospheres of exoplanets in TRAPPIST-1 habitable zone probed
This artist’s concept shows what the TRAPPIST-1 planetary system may look like, based on available data about the planets’ diameters, masses, and distances from the host star, as of February 2018.
Astronomers using NASA’s Hubble Space Telescope have conducted the first spectroscopic survey of the Earth-sized planets (d, e, f, and g) within the habitable zone around the nearby star TRAPPIST-1. This study is a follow-up to Hubble observations made in May 2016 of the atmospheres of the inner TRAPPIST-1 planets b and c.
Hubble reveals that at least three of the exoplanets (d, e, and f) do not seem to contain puffy, hydrogen-rich atmospheres similar to gaseous planets such as Neptune.
Additional observations are needed to determine the hydrogen content of the fourth planet’s (g) atmosphere. Hydrogen is a greenhouse gas, which smothers a planet orbiting close to its star, making it hot and inhospitable to life. The results, instead, favor more compact atmospheres like those of Earth, Venus, and Mars.
By not detecting the presence of a large abundance of hydrogen in the planets‘ atmospheres, Hubble is helping to pave the way for NASA’s James Webb Space Telescope, scheduled to launch in 2019. Webb will probe deeper into the planetary atmospheres, searching for heavier gases such as carbon dioxide, methane, water, and oxygen. The presence of such elements could offer hints of whether life could be present, or if the planet were habitable.
“Hubble is doing the preliminary reconnaissance work so that astronomers using Webb know where to start,” said Nikole Lewis of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, co-leader of the Hubble study. “Eliminating one possible scenario for the makeup of these atmospheres allows the Webb telescope astronomers to plan their observation programs to look for other possible scenarios for the composition of these atmospheres.”
The planets orbit a red dwarf star that is much smaller and cooler than our Sun. The four alien worlds are members of a seven-planet system around TRAPPIST-1. All seven of the planetary orbits are closer to their host star than Mercury is to our Sun. Despite the planets’ close proximity to TRAPPIST-1, the star is so much cooler than our Sun that liquid water could exist on the planets’ surfaces.
Two of the planets were discovered in 2016 by TRAPPIST (the Transiting Planets and Planetesimals Small Telescope) in Chile. NASA’s Spitzer Space Telescope and several ground-based telescopes uncovered five additional ones, increasing the total number to seven. The TRAPPIST-1 system is located about 40 light-years from Earth.
“No one ever would have expected to find a system like this,” said team member Hannah Wakeford of STScI. “They’ve all experienced the same stellar history because they orbit the same star. It’s a goldmine for the characterization of Earth-sized worlds.”
The Hubble observations took advantage of the fact that the planets cross in front of their star every few days. Using the Wide Field Camera 3, astronomers made spectroscopic observations in infrared light, looking for the signature of hydrogen that would filter through a puffy, extended atmosphere, if it were present. “The planets are close enough to their host star, and they have very short orbital periods, which means there are lots of opportunities to make observations,” Lewis said.
Although Hubble did not find evidence of hydrogen, the researchers suspect the planetary atmospheres could have contained this lightweight gaseous element when they first formed. The planets may have formed farther away from their parent star in a colder region of the gaseous protostellar disk that once encircled the infant star.
“The system is dynamically stable now, but the planets could not have formed in this tight pack,” Lewis said. “They’re too close together now, so they must have migrated to where we see them. Their primordial atmospheres, largely composed of hydrogen, could have boiled away as they got closer to the star, and then the planets formed secondary atmospheres.”
In contrast, the rocky planets in our solar system likely formed in the hotter, dryer region closer to the Sun. “There are no analogs in our solar system for these planets,” Wakeford said. “One of the things researchers are finding is that many of the more common exoplanets don’t have analogs in our solar system. So the Hubble observations are a unique opportunity to probe an unusual system.”
The Hubble team plans to conduct follow-up observations in ultraviolet light to search for trace hydrogen escaping the planets’ atmospheres, produced from processes involving water or methane lower in their atmospheres.
Astronomers will then use the Webb telescope to help them better characterize those planetary atmospheres. The exoplanets may possess a range of atmospheres, just like the terrestrial planets in our solar system.
“One of these four could be a water world,” Wakeford said. “One could be an exo-Venus, and another could be an exo-Mars. It’s interesting because we have four planets that are at different distances from the star. So we can learn a little bit more about our own diverse solar system, because we’re learning about how the TRAPPIST star has impacted its array of planets.”
Edited by Ariasun editorial board
Source:
for ariasun products online shopping ,click here.
https://www.instagram.com/ariasunintlgroup
website ariasuniweb net ariasuniportal ariasuni Health Journal Family physician Medical Health Ariasan Elcomp </ em> Elcomp Exhibition </ em> Online Elcomp Therapy Health Electronics Tourism Aryans City Net Soocom Ariasun Soopak Ariasun medipharma Advertisement Reader The requirements Employment Currency Exchange Currency Coin Gold < em> car property land building stock exchange bank Government People Leader Assembly Quran Book Student University Knowledge base Exercise Sima Sound Religion < / em> Life People Hope Work Dread Unemployment youth exercise information technology computer < / em> Hardware Software Computer Server Virtual Tablet < / em> Mobile Zanjan Tehran Iran Germany Greece Georgia Georgia Dubai World Air Space < em> Country Product Finder AriaSun International Group Online Store WikiPharma AriaSun Production Industrial Operations Equip Installation & Investment Air Space International Trading Research Industrial Business Medical Dummy Undoubtedly Health Drug Therapy Health Information Technology & Computer Airlines Tourism Logo Design Sticker Design Advertising Campaign Science & Research News </em > Political News Economic Trade International Stock Market News Medical Tourism & Cultural Heritage Aeronautics & Tourism Sport & Olympic Domain and University The Quran Arts & Culture Industry & Technology Accidents Ladies Currency and Gold Coins Flats Rip’s Web Site Kandasheh Ahwaz Web Site Foot Website Abuse Clean Sean Cinere Live Nature Whats Punababy Mussels Clinic Radarians Man AriaSun Preddies Reservations < Em> Tourists Unemployment youth exercise CityNet PakSaman SooComAriaSun SooPakAriaSun MediPharma AriaSun Kalayab AriaSunBazar AriaSunBazar Medeca MediKala Artists Group AriaSunGroup Web site designing RP Pilgrimage website Historical tours website Web Resident Resorts site Tours website The Pana The Natural Tours Website Kandesheh Ahwaz The Scientific Tour Website Oil & Refineries The Sports Tour Website Gas The Web Tours Water Exposure Tour Site Travel Tour Website Travel Tours The Last-minute Tours Site Tours of the last minute Web-site of the local tours Recreation site Internal tours site Pilgrimage Fun Places Design Web Design City Net Designing a Holiday Resort Pilgrimage Pilgrimage Website designing pilgrimage City Net Pilgrimage Travel </em > Designing Travel Planner Website Designing Travel Places Historic Places Designing Historic Places Historic Places Design Residences Residential Residential Design Residential Residential Design Cultural Places Designing a Web Site for Cultural Places Designing Cultural Places Natural Places Natural Places Designing a natural site Designing a natural website scientific Designing for scientific Designing for scientific sports sports designing sports < Em> Sports Facilities Design Sports Facilities Sport Sport Designing a Sports Center for Extreme Sports Creating places Designing for Exhibition Exhibit places Designing Exhibit Places Designing Exposure Website Web Recreation Recreation Web Design Recreational tours The design of the tourist resorts Pilgrimage Pilgrimage Pilgrimage Pilgrimage Pilgrimage Tours Historic Tours Tour Design Historic Tours Web Tour Design Historical Tours Residential Tours Resorts Tour Design Residential Tour Website Design Cultural Design Cultural Tour Site Cultural Tour Website Natural Designing Natural Tours Designing Natural Tours Web Site Science Designing Scientific Tours Designing Sci-Fi Web Site Designing a Sports Tour Designing a Sports Tour Website Designing a Tours Tour Designing a Touring Web Site Exhibit Exhibit Tour Travel Designing Tours Tour The Last Moment Toure The Last Moment Designing the Last Minute Tours Internal Tours Designing Local Tours Designing a Web Site Tour </em > Foreign Tours Designing a Tours Site Designing a Website for Tours Coastal Work < em> Designing the Coast Guided Tour Urban Designing Urban Tours Urban Touring Sights < Em> Sightseeing Design Sightseeing Web Site Mountaineering Sailing Designing Sailing Tours < Em> Website Designing Sailing Tours Aviation Designing Tours Cruising Cruising ships Creating cruise ship cruises Creating Cruise Cruises Inbound Flights Designing Inbound Flights Foreign Flights Designing a Foreign Airmail Web site Last Minute Flights Web Design Last Minute Deals cheap Website Design Cheap Flights Online Shopping Online Sales Online Selling Website Design Online Shopping Online Store Online Store Design Online Tickets Design an Online Ticket Internet Designing a Web Store Internet Tickets Designing an Internet Ticket > parscoders






  374 Visit

Search
Commercial
Public Relations
Finance & Administration
Soopak Ariasun ( IT )
Sookam Ariasun ( Medical and Veterinary )
Aerospace ( Pad Ariasun )
Manufacture and production ( Rad Ariasun )
Airline and Tourism ( Man Ariasun )
International Commerce ( Mad Ariasun )
Research Center Ariasun ( R&D&C )
Cultural,Satellite and Digital
AriaSun International Group
Submit Your Comment
?Want to join the discussion!Feel free to contribute