4 ms·
what does the light come from?
by dm319 4y ago
what does the light come from?
- tanbog5 4y agoThe Sun I think.
- op00to 4y agoThe flash is the energy (heat, light) generated by the forces of impact. The asteroid has incredible amounts of energy since it was likely moving very fast compared to the Moon, and it's got to go somewhere.
- Eduard 4y agoLayman here. Considering there is no atmosphere on the moon, and stone's conduction properties, does that mean the short flash of light (radiation) was most of the heat energy the impact produced?
- varjag 4y agoYou see the part of the spectrum the camera sensor was able to capture. Most of the energy went into displacing/melting the regolith and the shockwave.
- wheelerof4te 4y agoThere's no shockwave since there's no air on the Moon.
- amelius 4y agoThere can be a shockwave along the surface, I suppose, for example.
- op00to 4y agoCould there be a shockwave through the Moon itself?
- wheelerof4te 4y agoPossibly, since the regolith is a good conductor.
- deleted 4y ago[deleted]
- varjag 4y agoI meant in the regolith. Can't say if it exceeded the speed of sound in the medium there but given typical impact speeds it probably did. But we can call it a quake if you prefer.
- wheelerof4te 4y agoYes. There would be no shockwave, just some light and incredible amounts of very localized heat.
- marginalia_nu 4y agoAre we sure it didn't just kick up dust into the sunlight? Looks like the sun might have been just below the horizon.
- gibmeat 4y agoI thought about this too, but if it were dust, I'm guessing it wouldn't dissipate in 1 second.
- marginalia_nu 4y agoSeems like atmospheric intuition. I'd expect high velocity dust to diffuse rather quickly in near vacuum.
- icehawk 4y agoHere's a 2.8km/sec dust cloud from DART for comparison: https://www.virtualtelescope.eu/wordpress/wp-content/uploads/2022/09/DARTimpactDimorphos_26sept2022_panel.jpg?x31283 https://www.virtualtelescope.eu/wordpress/wp-content/uploads...
- op00to 4y agoIf it kicked up dust, would the dust keep going, or would the Moon’s gravity pull it back to the lunar surface quickly? I have no idea.
- cornstalks 4y agoThe moon’s escape velocity is 2.38 km/s (5324 miles/hour), so it just depends on whether or not the material reached escape velocity or not.
- op00to 4y agoThank you for this! Totally made it click in my head.
- 4y ago
- TrapLord_Rhodo 4y agoIt discusses this in the article. The regolith 'Glows' from the kenetic energy transfer, and heat disipation.