It is most likely that there was an impact on the Moon during yesterday's lunar eclipse. I am trying to get some more understanding of this so that I could maybe do a more detailed video on this incident.

Assuming that there actually was an impact of an asteroid or some other sort of object, it is clear that the flash was generated by the event itself and any influence of sunlight or earthshine can be ruled out. Also, the virtually non-existent Lunar atmosphere does not allow for notable entry heating.

Of course, there is a huge amount of energy involved in such a collision. There are many ways this energy could be converted into radiation, e.g. by some sort of luminescence. Could it also be possible that there is combustion involved? Which of the possible effects is dominating?

I would also be thankful for hints on scientific work that has been done on this topic.

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    $\begingroup$ I suspect it's basically - high kinetic energy converting rock to plasma very rapidly. No research to back my hunch though, so it's best answered by someone else. $\endgroup$
    – Saiboogu
    Jan 22 '19 at 16:47
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    $\begingroup$ Yes, that's it - kinetic energy dissipated as massive amount of heat, causing the impact material to glow brightly. $\endgroup$
    – SF.
    Jan 22 '19 at 16:51
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    $\begingroup$ This effect is called thermal radiation. $\endgroup$
    – void_ptr
    Jan 22 '19 at 17:36
  • $\begingroup$ @void_ptr I wrongly assumed thermal radiation was included in the multitude of different kinds of luminescence (thermoluminescence), but that's not the case. What I find odd about this possibility is the time scale at which the event took place. I thought cooling by black body radiation takes some time. Like Saiboogu's plasma thought. $\endgroup$ Jan 22 '19 at 18:57
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    $\begingroup$ @EverydayAstronaut cooling by black body radiation takes some time for larger objectsm but not for small dust paticles. It is the relation between surface to volume that influences the cooling rate. $\endgroup$
    – Uwe
    Jan 22 '19 at 20:17

Here is an example of a similar test done on Earth. There is a similarly bright flash. Basically the impact. Stanford clarifies that a portion of the impact energy goes in to creating a plasma, with a charged state. That energy will show a brief flash of light, as seen in the impact tests and this video.

  • $\begingroup$ Side note: It was really fun looking for a video to demonstrate this. $\endgroup$
    – PearsonArtPhoto
    Jan 22 '19 at 19:02
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    $\begingroup$ Sorry, lost the source on my other computer, will check it in the morning... Sigh. $\endgroup$
    – PearsonArtPhoto
    Jan 23 '19 at 3:56
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    $\begingroup$ There, found the link and added it. Hopefully that helps. $\endgroup$
    – PearsonArtPhoto
    Jan 23 '19 at 13:17
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    $\begingroup$ thanks! It's interesting that the plasma will also generate a substantial radio pulse along with the optical one. i.stack.imgur.com/Ha9nS.png $\endgroup$
    – uhoh
    Jan 23 '19 at 13:25

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