Small Asteroid Impacts Moon | Hacker News Reader

Small Asteroid Impacts Moon

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Now Samsung has to patch their Moon template.

shit came here to make this joke

What do you mean with moon template?

They were caught faking zoomed in photos of the moon on their phones with AI filling in details.

https://old.reddit.com/r/Android/comments/11nzrb0/samsung_sp...

Did you see the HN comment? He basically said he was over redditors and loved the Convo on HN.

https://news.ycombinator.com/item?id=35107601 <Insert it is known GIF>

Lol me too

Me x4!

Got down voted for my comment, save yourself.

I am still figuring out participating in HN conversations but this downvote seems excessive no?

It's not reddit you see. So read up on it. I'm actually a terrible HN commenter myself but I do like the attempt to keep striving for the almighty laugh as a low priority here on HN.

If you should comment, then contribute and don't just go for the easy joke or vapid comment.

Probably was shot with a Samsung phone

This is clearly a joke btw

AI translation:

- "I was able to catch the biggest lunar impact flash in my observation history! This is a picture of the lunar impact flash that appeared at 20:14:30.8 on February 23, 2023, taken from my home in Hiratsuka (replayed at actual speed). It was a huge flash that continued to shine for more than 1 second. Since the moon has no atmosphere, meteors and fireballs cannot be seen, and the moment a crater is formed, it glows."

- "This is a picture of the lunar impact flash at 20:14:30.8 on February 23, 2023, captured by another telescope (playback at actual speed). At that time, the altitude of the moon was only 7 degrees, and I was glad that I could stick to the limit. At the time of observation, there was no satellite passing over the lunar surface, and from the way it shines, it is highly likely that it is a lunar impact flash."

- "This is a still image of the lunar impact flash at 20:14:30.8 on February 23, 2023. It seems to have fallen near Ideler L crater, slightly northwest of Pitiscus crater. Because it is so bright, the generated crater is large, and the striations are clearly visible. It seems that the telephoto camera of NASA's lunar probe LRO can detect the fall trace."

The late Patrick Moore did a lot of work on what he termed transient lunar phenomena, essentially lights, or "clouds" on the moon, due to some unknown geological process.

https://en.wikipedia.org/wiki/Transient_lunar_phenomenon

Bottom right corner (took me a while to notice it so near the text).

thank you!

I was able to click on the video to view it full screen, then there is no text. (Also took me a while to figure this out.)

https://twitter.com/oldspica/status/1630425706290360321

""" I magnified the location of lunar surface impact flash observed by Fujii Daichi-san on February 23 with 25cm reflection (telescope). It's near Ideler L crater according to Fujii-san. Unfortunately I was not able to discern anything like a new crater.

I thought I would be able to tell if the diameter was larger than 2km?! ...

I compared with with America's Lunar Reconnaissance Orbiter, but can't really tell.

Even with such a flash, was that impact crater too small to be easily seen by telescope? """

How rare are these impacts? Are they like once in a lifetime observations, about once a year, or what?

Nasa has a Program called "Lunar Impact Monitoring".

See:

https://link.springer.com/article/10.1007/s11038-007-9184-0

https://ntrs.nasa.gov/api/citations/20150021386/downloads/20...

http://lunarnetworks.blogspot.com/2013/05/brightest-impact-r...

The data collected by the "Lunar Reconnaissance Orbiter" can be used to estimate the frequency of impacts.

https://www.lroc.asu.edu/posts/943

This paper found 222 impacts when comparing repeat LRO images (2009-present): https://www.nature.com/articles/nature19829

I'm leading new a citizen science project called MoonDiff, comparing against older images to look further back in time -- contact me if interested.

https://moondiff.org

https://trek.nasa.gov/moondiff/static/moondiff_intro.webm

https://github.com/nasa-jpl/moondiff

How Are Places on the Moon Named? https://www.smithsonianmag.com/air-space-magazine/how-are-pl...

Planetary Names: How Names Are Approved https://planetarynames.wr.usgs.gov/Page/Approved

I wonder how big it was. Seems like it would have to be pretty big to be that bright, but maybe it's one of those things that defy our regular intuition.

I don't know, but compared to the scale of the gigantic crater that's visible in the image, whatever it was was pretty much nothing in the grand scheme.

The impact that made that huge crater must have been an amazing light show...

I bet it did. The dinosaurs were probably impressed.

I've never thought of this before, but I imagine the ground could have glowed for minutes or hours, and been visible from Earth. That would have been quite something to see from a safe distance.

Doesn't have to be that big really.

The brightness is a function of momentum, meaning, it could be large or it could just be unfathomably fast.

What would create the brightness/light on such impact?

Energy dissipation. It's enough energy to temporarily heat the rock and the impactor to the point that they start glowing very brightly.

Why momentum rather than kinetic energy?

Rather than size, I wonder how much energy the impact released. Waiting for the videos that will do a simulation of what would have happened if this have hit earth.

what does the light come from?

The Sun I think.

The 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.

Layman 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?

You 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.

There's no shockwave since there's no air on the Moon.

There can be a shockwave along the surface, I suppose, for example.

Could there be a shockwave through the Moon itself?

Possibly, since the regolith is a good conductor.

I 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.

Yes.

There would be no shockwave, just some light and incredible amounts of very localized heat.

Are we sure it didn't just kick up dust into the sunlight?

Looks like the sun might have been just below the horizon.

I thought about this too, but if it were dust, I'm guessing it wouldn't dissipate in 1 second.

Seems like atmospheric intuition.

I'd expect high velocity dust to diffuse rather quickly in near vacuum.

Here's a 2.8km/sec dust cloud from DART for comparison:

https://www.virtualtelescope.eu/wordpress/wp-content/uploads...

If 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.

The 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.

Thank you for this! Totally made it click in my head.

In my layman opinion a dust cloud would at very least stick around for much longer than the duration that we see this glowing last. There has to be something else responsible for the flash imo.

It discusses this in the article. The regolith 'Glows' from the kenetic energy transfer, and heat disipation.

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