Comments by "Digital Nomad" (@digitalnomad9985) on "Puffball Planets" video.

  1. Don't forget inevitable sampling bias. By Doppler wobble of the star, by transit, or by direct observation, it is much easier to detect planets that are larger and/or closer to their primary. If puffballs are rare, we will not have found many distant cool ones by now. To be clearer we will not have found as high a proportion of those that exist as we have of the hot ones. Hot puffballs become so by vaporizing volatile rock. Cold puffballs can retain volatiles better.
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  2. That is true of objects that glow from heat because of the black body radiation curve. As the black body gets hotter it first enters the red end of the visible spectrum and the rest of it is lower frequency that we can't see. The curve slopes up from the lower frequencies and drops off rapidly higher than the peak. Getting hotter, it proceeds through orange to yellow, and when the peak gets to green or blue, because the lower frequency part of the curve slopes gradually, it's glowing pretty evenly through the visible spectrum and looks white. As it gets hotter than that it keeps looking white and just gets brighter, even as the peak of radiation is emitted in higher frequencies, UV, then X-ray, then gamma that we can't see.
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