Direct observation using Spitzer/IRAC. Basically, we can see change of infrared emissions between day and night that suggest there is no gas insulating the darkside from heat loss at night. It's covered in https://iopscience.iop.org/article/10.1088/0004-637X/703/2/1884/meta … (Paywalled unless u r .edu)
Spitzer Space Telescope 
#NASAWebb
Webb researchers plan to explore rocky exoplanet LHS 3844b, building off Spitzer’s discoveries: https://go.nasa.gov/3nfrELQ pic.twitter.com/nWliV5FaFd
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this telescope will bring us good news soon
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Why does anyone care about a exoplanet without a atmosphere?
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We are not sure if it has no atmosphere.
End of conversation
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When FFS? Why isn't the Webb up now?
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So, at first, I definitely read that as “weeb researchers”
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Bring on The Webb!
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