时间:2025-05-01 16:27:05 来源:网络整理编辑:綜合
The search for a rocky world swaddled in a protective atmosphere somewhere else in space has eluded
The search for a rocky world swaddled in a protective atmosphere somewhere else in space has eluded scientists, but the James Webb Space Telescope has found a strong case.
Webb, the leading infrared observatory run by NASA and the European and Canadian space agencies, has taken a closer look at super-Earth 55 Cancri e, an exoplanet blanketed in either carbon dioxide or carbon monoxide just 41 light-years away.
But to call it an "Earth-like world" would be misleading. Discovered 13 years ago in the constellation Cancer, the planet seems to orbit so close to its star, its surface is probably lava. And because it's hugging the star so tightly, chances are it isn't rotating either, with one side in constant darkness.
Still, the discovery could be the best evidence scientists have found of a rocky planet's atmosphere outside Earth's own solar system. Such a finding, published in the journal Nature, bolsters experts' confidence that they'll eventually discover rocky worlds with hospitable atmospheres.
"Webb is pushing the frontiers of exoplanet characterization to rocky planets," said Renyu Hu, a researcher at NASA's Jet Propulsion Laboratory, in a statement. "It is truly enabling a new type of science."
SEE ALSO:Webb may have just found an Earth-like world with an atmosphereTweet may have been deleted
When exoplanets cross in front of their host star, the star’s light is filtered through that atmosphere. Molecules within the atmosphere absorb certain light wavelengths, or colors, so by splitting the star’s light into its basic parts — a rainbow — astronomers can use Webb to detect what light segments are missing and discern the molecular makeup of an atmosphere.
Scientists have found signs of atmospheres surrounding many exoplanets over the past 20 years, but all of them have been gas giant planets, like Jupiter, with thick atmospheres mostly composed of hydrogen.
Knowing what's in another planet's atmosphere is important. NASA has playfully called Earth's own atmosphere its "security blanket": Without it, the type of life flourishing on the planet wouldn't exist. This cocoon holds oxygen in the air and filters out harmful ultraviolet radiation from the sun, all while keeping our world warm and habitable. Furthermore, it creates pressure that allows liquid water to exist on Earth's surface.
The first sign that 55 Cancri e could have a substantial atmosphere came from temperature readings based on the infrared light it radiates. If the planet is covered in dark molten rock with no atmosphere — or a very thin one of vaporized rock — the side in constant light should be about 4,000 degrees Fahrenheit.
Instead, the researchers found a much lower temperature of about 2,800 degrees Fahrenheit.
"This is a very strong indication that energy is being distributed from the dayside to the nightside, most likely by a volatile-rich atmosphere," Hu said.
While 55 Cancri e would seem far too hot to support life as we know it, scientists think studying it could enhance their understanding of the primitive conditions of Earth, Venus, and Mars, which some believe were also once covered in magma oceans.
"Ultimately, we want to understand what conditions make it possible for a rocky planet to sustain a gas-rich atmosphere: a key ingredient for a habitable planet,” Hu said.
TopicsNASA
Researchers create temporary tattoos you can use to control your devices2025-05-01 16:24
水慶霞 :比賽銜接上還有問題 唐佳麗出現可喜改變2025-05-01 15:53
曝河南隊拒與伊沃續約 周定洋合約到期未收歸隊通知2025-05-01 15:50
巧合?本賽季西甲武磊9場枯坐板凳 球隊勝率僅22%2025-05-01 15:44
5 people Tim Cook calls for advice on running the biggest company in the world2025-05-01 15:29
水慶霞 :比賽銜接上還有問題 唐佳麗出現可喜改變2025-05-01 15:22
越南主帥關注球員文身 囑咐年輕隊員要集中精力備戰2025-05-01 15:06
澳大利亞12強賽25人名單 :穆伊領銜 塞恩斯伯裏在列2025-05-01 14:54
Nate Parker is finally thinking about the woman who accused him of rape2025-05-01 14:40
越媒 :為擊敗越南隊 中國足協開出“恐怖的”贏球獎2025-05-01 14:13
You can now play 'Solitaire' and 'Tic2025-05-01 15:40
國足未來之星18歲生日感言:成年了 也要肩負起更多的責任2025-05-01 15:32
名宿:曼聯球員要更加謙遜 他們應該閉嘴聽C羅的話2025-05-01 15:23
一夜三記神仙球!兩次蠍子擺尾 插花腳助攻太騷氣2025-05-01 15:14
Singapore gets world's first driverless taxis2025-05-01 15:09
巴薩新王或賽季報銷!近73戰隻出場10次 極度沮喪2025-05-01 14:42
FIFA22最佳陣容:萊萬梅西攜手 巴黎=曼城+切爾西2025-05-01 14:10
感人!38歲阿爾維斯踢滿120分鍾 倒勾助攻精妙絕倫2025-05-01 14:09
Slack goes down again, prompting anxiety everywhere2025-05-01 14:01
武磊困守西班牙人難有機會 除非戰術改變或人員短缺2025-05-01 13:55