什么是“生物标志”气体？
What are biosignature gases?
生物标志是大气中可由生命产生、且非生物过程难以长期维持的气体组合，例如氧气与甲烷共存、或臭氧与甲烷并存，是搜寻地外生命的关键线索。
A biosignature is a gas combination in an atmosphere that life can produce and non-biological processes cannot easily sustain—such as oxygen with methane, or ozone with methane—a key clue in the search for alien life.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Chaisson & McMillan,《Astronomy Today》Pearson 多版
E. Chaisson and S. McMillan, Astronomy Today, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 标识 /works/OL1919527W（按标识回读: Astronomy tod
#生物标志 #大气 #生命探测
詹姆斯·韦布为何关注K2-18b上的二甲基硫醚（DMS）？
Why does JWST care about dimethyl sulfide (DMS) on K2-18b?
K2-18b是一颗位于宜居带的亚海王星，韦布在其大气中发现可能的DMS信号——在地球上DMS主要由海洋浮游生物产生，但该结果仍有争议、需复测确认。
K2-18b is a habitable-zone sub-Neptune where Webb found a possible DMS signal—on Earth DMS is mainly made by ocean phytoplankton—but the result is debated and needs confirmation.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-04结论有争议 · Contested
来源 · Source
Catling, Krissansen-Totton, Kiang & Crisp,《Exoplanet Biosignatures: A Framework for Their Assessment》,Astrobiology,2018 (DOI: 10.1089/ast.2017.1737)
Catling, Krissansen-Totton, Kiang & Crisp, 'Exoplanet Biosignatures: A Framework for Their Assessment', Astrobiology, 2018, DOI: 10.1089/ast.2017.1737
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1089/ast.2017.1737
#K2-18b #二甲基硫 #争议
什么是系外卫星（exomoon），如何寻找？
What is an exomoon and how do we find one?
系外卫星绕系外行星运行，可能像木卫二一样拥有液态水海洋；寻找方法包括凌星时的次级掩食和凌星时长变化，目前尚无确证发现。
An exomoon orbits an exoplanet and could host liquid-water oceans like Europa; hunters look for secondary eclipses during transit and transit-timing variations, but none is confirmed yet.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Chaisson & McMillan,《Astronomy Today》Pearson 多版
E. Chaisson and S. McMillan, Astronomy Today, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 标识 /works/OL1919527W（按标识回读: Astronomy tod
#系外卫星 #木卫二 #探测
韦布观测TRAPPIST-1行星大气得到了什么结果？
What did JWST find in TRAPPIST-1 planet atmospheres?
韦布对TRAPPIST-1 e、f、g等高灵敏度观测未发现明显大气信号，提示这些岩石行星可能大气稀薄或已被恒星辐照剥离，使红矮星系的宜居前景更谨慎。
Webb's sensitive look at TRAPPIST-1 e, f and g found no clear atmospheric signal, suggesting these rocky planets may have thin atmospheres or have been stripped by stellar irradiation, making red-dwarf habitability more cautious.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Gardner J. P. et al., The James Webb Space Telescope, Space Science Reviews 123 (2006), DOI: 10.1007/s11214-006-8315-7
Gardner J. P. et al., The James Webb Space Telescope, Space Science Reviews 123 (2006), DOI: 10.1007/s11214-006-8315-7
独立核验依据 · Independent verification: 核验依据 1 INSPIRE 标识 10.1007/s11214-006-8315-7：The James Webb Spac
#TRAPPIST-1 #大气 #红矮星
什么是大气逃逸，它对系外行星意味着什么？
What is atmospheric escape and what does it mean for exoplanets?
大气逃逸是行星大气被恒星辐射和星风逐渐剥离的过程；被强烈辐照的近距离行星（尤其热木星）会损失氢等轻元素，决定其能否长期保有大气与液态水。
Atmospheric escape is the gradual loss of a planet's air to stellar radiation and wind; strongly irradiated close-in planets, especially hot Jupiters, lose light elements like hydrogen, deciding whether they keep an atmosphere and liquid water.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Chaisson & McMillan,《Astronomy Today》Pearson 多版
E. Chaisson and S. McMillan, Astronomy Today, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 标识 /works/OL1919527W（按标识回读: Astronomy tod
#大气逃逸 #氢 #宜居性
红矮星周围的行星为何宜居性存疑？
Why is habitability doubtful around red-dwarf planets?
红矮星频繁爆发强烈耀斑和X射线，可能剥离行星大气、破坏表面生命，使处于宜居带的行星实际并不宜居。
Red dwarfs frequently erupt with strong flares and X-rays that can strip a planet's atmosphere and damage surface life, making habitable-zone planets there practically less habitable.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Chaisson & McMillan,《Astronomy Today》Pearson 多版
E. Chaisson and S. McMillan, Astronomy Today, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 标识 /works/OL1919527W（按标识回读: Astronomy tod
#红矮星 #耀斑 #大气剥离
什么是潮汐加热，它如何影响卫星的宜居性？
What is tidal heating and how does it affect moon habitability?
受主星与邻近天体引力拉扯，卫星内部摩擦生热；木卫二和土卫二因此拥有冰下海洋，成为太阳系内潜在宜居的热点。
Tugged by its planet and neighbors, a moon's interior heats from friction; Europa and Enceladus thus host subsurface oceans, making them prime habitability candidates in the Solar System.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Chaisson & McMillan,《Astronomy Today》Pearson 多版
E. Chaisson and S. McMillan, Astronomy Today, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 标识 /works/OL1919527W（按标识回读: Astronomy tod
#潮汐加热 #木卫二 #地下海洋
行星的反照率如何影响气候？
How does a planet's albedo affect its climate?
反照率衡量行星反射阳光的比例；高反照率（如冰覆盖）使行星更冷，低反照率（如深色岩石）吸收更多热量，是判断行星温度与宜居的关键参数。
Albedo measures the fraction of sunlight a planet reflects; high albedo (ice cover) keeps it cooler, low albedo (dark rock) absorbs more heat—a key parameter for temperature and habitability.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Chaisson & McMillan,《Astronomy Today》Pearson 多版
E. Chaisson and S. McMillan, Astronomy Today, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 标识 /works/OL1919527W（按标识回读: Astronomy tod
#反照率 #气候 #行星温度