Starship Asterisk*

Rocket Transits Rippling Moon

Explanation: Can a rocket make the Moon ripple? No, but it can make a background moon appear wavy. The rocket, in this case, was a SpaceX Falcon Heavy that blasted off from NASA's Kennedy Space Center last week. In the featured launch picture, the rocket's exhaust plume glows beyond its projection onto the distant, rising, and nearly full moon. Oddly, the Moon's lower edge shows unusual drip-like ripples. The Moon itself, far in the distance, was really unchanged. The physical cause of these apparent ripples was pockets of relatively hot or rarefied air deflecting moonlight less strongly than pockets of relatively cool or compressed air: refraction. Although the shot was planned, the timing of the launch had to be just right for the rocket to be transiting the Moon during this single exposure.

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I think the ripples are shock waves, and are not caused by "pockets of relatively hot or rarefied air deflecting moonlight less strongly than pockets of relatively cool or compressed air.."

Whether shock waves or heat, the unanswered question is whether it’s tied to the rocket launch, or some broader condition.

FLPhotoCatcher wrote: ↑Tue Jan 02, 2024 6:31 am I think the ripples are shock waves, and are not caused by "pockets of relatively hot or rarefied air deflecting moonlight less strongly than pockets of relatively cool or compressed air.."

I agree. The given explanation sounds too fancifully conceived. What pockets? Where did they come from?

The moon also happens to show turquoise-green and reddish-orange rims, a known atmospheric phenomenon.

Right, the ultimate (distal) cause of the ripples is shockwaves from the exhaust, not hot or rarified air. The link from the text had this to say:

https://apod.nasa.gov/apod/ap221014.html wrote:Ripples and fringes along the edge of the lunar disk appear as supersonic shock waves generated by the rocket's passage change the atmosphere's index of refraction.

However, the shockwaves from the exhaust are just ripples of varying density in the air, which amounts to differences in the air's "rarifiedness", which is the proximate cause of the light's refraction, so I would argue that the text isn't entirely incorrect, just lacking in clarity.

The spikiness on the left side starts at the 9:30, or 270+ position. I would hope the artificial explanations are being reviewed.