Just a quick note: the Falcon 9 carrying Firefly’s Blue Ghost lunar lander (and a second attempt Japanese mission to land called Resilience) launched successfully last night, and the spacecraft(s) are on their way to the Moon! Read all about it on Nature.com in an article by Alexandra Witze. 

This is pretty amazing: A small meteoroid turned into a meteorite in Canada’s Prince Edward Island after it smacked into a tile walkway outside someone’s home last July. If I’m reading the news article about it correctly, it was just confirmed to be an actual meteorite, a common ordinary chondrite.

What’s super cool about this is that there is video with sound of the impact!

WHOA. In one frame of the video you can actually see the rock just before it hit.

Now, you may be confused. Where’s the flash of light, the kaBLAM of impact, the giant smoking hole and flames?

Yeah, despite every movie ever made about impacts, that almost never happens. You need a pretty big rock to actually do that, thanks to our atmosphere. Incoming space rocks are moving pretty rapidly, usually around 20 or more kilometers per second. When smaller ones (say, less than 20 meters across) hit the air up there, though, around 90 – 100 km up they experience huge drag forces that slow them down very rapidly. That’s why you get the meteor; the air in front of the rock compresses violently and heats up, vaporizing the leading edge of the rock and creating the brilliant glow of the meteor.

That happens in just a few seconds, slowing from 70,000+ kph to terminal velocity, usually around 200 kph or so, depending on its size (this part of the journey is call the dark flight). In this case, the meteoroid (the solid rock part) was only around 100 grams, so it impacted not much faster than a fastball. Enough to leave a mark and make that fun shattering noise, but nowhere near enough energy to star in a Hollywood movie.

In fact, most meteorites like this are cold to the touch after impact; they spent several minutes falling slowly though the upper atmosphere, which is cold. Plenty of time to chill. 

I think that may be my favorite thing about this story: it shows directly that small meteorites don’t set fires, which is an incredibly common misconception. Now when someone finds a firework in their yard and claims it’s a meteorite, I can show them video proof it isn’t.

Bittersweet news: the Gaia spacecraft has closed its eye on the galaxy.

If you’ve read my stuff for any length of time then you’ve read about this ridiculously cool mission. The European Space Agency observatory doesn’t take gorgeous images or anything like that, but instead does something that is equally as important: it measures the positions, colors, motions, and distances of nearly two billion stars in the galaxy.

Or “measured”, I should say. After 11 years in orbit around the Sun, it’s run out of fuel needed to keep it pointed correctly, so yesterday, Wednesday, January 15, 2025, mission operators shut down its science operations.

Become a paying subscriber of Premium to get access to this post and other subscriber-only content.

Already a paying subscriber? Sign In.

A subscription gets you:

• • Three (3!) issues per week, not just one
• • Full access to the BAN archives
• • Leave comment on articles (ask questions, talk to other subscribers, etc.)