Thermal emission from the Earth-sized exoplanet TRAPPIST-1 b using JWST
Thermal emission from the Earth-sized exoplanet TRAPPIST-1 b using JWST
复制标题
使用 JWST 观测地球大小的系外行星 TRAPPIST-1 b 的热辐射
作者：
T. Greene;T. Bell;E. Ducrot;A. Dyrek;P. Lagage;J. Fortney
TRAPPIST-1系统因其七颗行星而引人注目，这些行星在大小、质量、密度和恒星加热方面与太阳系中的岩石行星金星、地球和火星相似^ 1。所有TRAPPIST-1行星都是用哈勃或斯皮策太空望远镜用透射光谱观测到的，但没有探测到大气特征或强烈约束^ 2 - 5。trappist - 1b是该系统中距离m矮星最近的行星，它接收到的辐射是地球从太阳接收到的辐射的四倍。这种相对较大的恒星加热表明它的热辐射是可以测量的。本文利用詹姆斯·韦伯太空望远镜（JWST）中红外仪器的F1500W滤光片，对地球大小的系外行星TRAPPIST-1 b进行了光度观测。我们在5次观测中发现了次食，当所有数据合并时，置信度为8.7 σ。这些测量结果与TRAPPIST-1恒星入射通量的再辐射最一致，这些再辐射仅来自行星的白天半球。最直接的解释是，很少或根本没有行星大气重新分配来自主星的辐射，也没有可探测到的大气吸收二氧化碳（CO_2）或其他物质。詹姆斯韦伯太空望远镜的观测表明，系外行星trappist - 1b几乎没有行星大气层，也没有可探测到的大气吸收二氧化碳。
The TRAPPIST-1 system is remarkable for its seven planets that are similar in size, mass, density and stellar heating to the rocky planets Venus, Earth and Mars in the Solar System^ 1 . All the TRAPPIST-1 planets have been observed with transmission spectroscopy using the Hubble or Spitzer space telescopes, but no atmospheric features have been detected or strongly constrained^ 2 – 5 . TRAPPIST-1 b is the closest planet to the M-dwarf star of the system, and it receives four times as much radiation as Earth receives from the Sun. This relatively large amount of stellar heating suggests that its thermal emission may be measurable. Here we present photometric secondary eclipse observations of the Earth-sized exoplanet TRAPPIST-1 b using the F1500W filter of the mid-infrared instrument on the James Webb Space Telescope (JWST). We detect the secondary eclipses in five separate observations with 8.7 σ confidence when all data are combined. These measurements are most consistent with re-radiation of the incident flux of the TRAPPIST-1 star from only the dayside hemisphere of the planet. The most straightforward interpretation is that there is little or no planetary atmosphere redistributing radiation from the host star and also no detectable atmospheric absorption of carbon dioxide (CO_2) or other species. Observations from the James Webb Space Telescope suggest that the exoplanet TRAPPIST-1 b has little or no planetary atmosphere and no detectable atmospheric absorption of carbon dioxide.
通过推断的高反照率识别岩石系外行星上的大气
DOI：
10.3847/1538-4357/ab4c90
发表时间：
2019
期刊：
The Astrophysical Journal
影响因子：
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作者：
Mansfield, Megan;Kite, Edwin S.;Hu, Renyu;Koll, Daniel D.;Malik, Matej;Bean, Jacob L.;Kempton, Eliza M.-R.
通讯作者：
Kempton, Eliza M.-R.