Starship Asterisk*

A Perseid Below

Explanation: Denizens of planet Earth typically watch meteor showers by looking up. But this remarkable view, captured on August 13, 2011 by astronaut Ron Garan, caught a Perseid meteor by looking down. From Garan's perspective on board the International Space Station orbiting at an altitude of about 380 kilometers, the Perseid meteors streak below, swept up dust from comet Swift-Tuttle. The vaporizing comet dust grains are traveling at about 60 kilometers per second through the denser atmosphere around 100 kilometers above Earth's surface. In this case, the foreshortened meteor flash is near frame center, below the curving limb of the Earth and a layer of greenish airglow, just below bright star Arcturus. Want to look up at a meteor shower? You're in luck, as the 2024 Perseid meteor shower is active now and predicted to peak near August 12. With interfering bright moonlight absent, this year you'll likely see many Perseid meteors under clear, dark skies after midnight.

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What would have happened if such a meteor as in the photo had hit the ISS?

To the left of Arcturus, towards the upper left edge of the image, we clearly recognize Corona Borealis, its star alpha (Alphecca) and epsilon Corona Borealis must be the site of a nova event between now and September. I watch it every night and so far, nothing.


Alex

Like Lasse, this made me think of "Gravity", and not in a good way.
Good luck to the crew of the ISS, as the Perseids peak.
John

Lasse H wrote: ↑Fri Aug 09, 2024 9:04 am What would have happened if such a meteor as in the photo had hit the ISS?

It would depend where it hit. Critical parts of the ISS are protected by shields that will block particles smaller than about a centimeter. The meteor in the image was probably produced by a particle only a few millimeters in diameter, so it would have been blocked. Other areas might have sustained minor damage or pitting. The ISS is covered with such pits.

Lasse H wrote: ↑Fri Aug 09, 2024 9:04 am What would have happened if such a meteor as in the photo had hit the ISS?

I have a little experience with bullets, such as the 5.56 mm bullets fired on j13. They weigh 4.02 gm, travel at 914.4 m/sec. They will dimple 6 mm mild steel, bounce off 6 mm plow steel. According to the post, the meteors are traveling 65 times as fast. So kinetic energy is 4225 times as great. A dust grain will vaporize itself and some of the iss on impact. Anything larger than a few milligrams will be damaging.

Roy wrote: ↑Fri Aug 09, 2024 2:34 pm

Lasse H wrote: ↑Fri Aug 09, 2024 9:04 am What would have happened if such a meteor as in the photo had hit the ISS?

I have a little experience with bullets, such as the 5.56 mm bullets fired on j13. They weigh 4.02 gm, travel at 914.4 m/sec. They will dimple 6 mm mild steel, bounce off 6 mm plow steel. According to the post, the meteors are traveling 65 times as fast. So kinetic energy is 4225 times as great. A dust grain will vaporize itself and some of the iss on impact. Anything larger than a few milligrams will be damaging.

But the ISS does have shielding to prevent or limit damage.

Roy wrote: ↑Fri Aug 09, 2024 2:34 pm

Lasse H wrote: ↑Fri Aug 09, 2024 9:04 am What would have happened if such a meteor as in the photo had hit the ISS?

I have a little experience with bullets, such as the 5.56 mm bullets fired on j13. They weigh 4.02 gm, travel at 914.4 m/sec. They will dimple 6 mm mild steel, bounce off 6 mm plow steel. According to the post, the meteors are traveling 65 times as fast. So kinetic energy is 4225 times as great. A dust grain will vaporize itself and some of the iss on impact. Anything larger than a few milligrams will be damaging.

What's "j13"?

What are the several splotches of orange seen on the Earth's surface (or in it's atmosphere)? Fires? Volcanos? Lightning?

johnnydeep wrote: ↑Fri Aug 09, 2024 5:59 pm What are the several splotches of orange seen on the Earth's surface (or in it's atmosphere)? Fires? Volcanos? Lightning?

Cities, I'd think.

Chris Peterson wrote: ↑Fri Aug 09, 2024 6:02 pm

johnnydeep wrote: ↑Fri Aug 09, 2024 5:59 pm What are the several splotches of orange seen on the Earth's surface (or in it's atmosphere)? Fires? Volcanos? Lightning?

Cities, I'd think.

Really? Hmm...

johnnydeep wrote: ↑Fri Aug 09, 2024 5:58 pm

Roy wrote: ↑Fri Aug 09, 2024 2:34 pm

Lasse H wrote: ↑Fri Aug 09, 2024 9:04 am What would have happened if such a meteor as in the photo had hit the ISS?

I have a little experience with bullets, such as the 5.56 mm bullets fired on j13. They weigh 4.02 gm, travel at 914.4 m/sec. They will dimple 6 mm mild steel, bounce off 6 mm plow steel. According to the post, the meteors are traveling 65 times as fast. So kinetic energy is 4225 times as great. A dust grain will vaporize itself and some of the iss on impact. Anything larger than a few milligrams will be damaging.

What's "j13"?

Answering my own dumb question: "j13" must be a reference to the assassination attempt on Trump on July 13, where the shooter used an AR-15 style rifle.

johnnydeep wrote: ↑Fri Aug 09, 2024 6:48 pm

Chris Peterson wrote: ↑Fri Aug 09, 2024 6:02 pm

johnnydeep wrote: ↑Fri Aug 09, 2024 5:59 pm What are the several splotches of orange seen on the Earth's surface (or in it's atmosphere)? Fires? Volcanos? Lightning?

Cities, I'd think.

Really? Hmm...

Sure, why not? It's exactly the right color for the typical sodium lamp city lighting we often see on ISS shots of the night side, and it's not transient (like lightning) because it's motion streaked by the motion of the ISS.

Chris Peterson wrote: ↑Fri Aug 09, 2024 7:27 pm

johnnydeep wrote: ↑Fri Aug 09, 2024 6:48 pm

Chris Peterson wrote: ↑Fri Aug 09, 2024 6:02 pm

Cities, I'd think.

Really? Hmm...

Sure, why not? It's exactly the right color for the typical sodium lamp city lighting we often see on ISS shots of the night side, and it's not transient (like lightning) because it's motion streaked by the motion of the ISS.

Ok. They seem too concentrated and isolated, but perhaps they are islands? Not sure what area of the globe this is.

I guess the green layer that follows the curvature of the Earth is airglow?

I don't remember seeing airglow in similar images from previous decades. Has airglow become more common?


Finally, you've got to check out this image that was taken on February 1, 2012, from the ISS:


Note the incredibly bright green aurora and a much fainter red aurora on top of the green one. Note the dull bronze hue of the atmosphere to the left of the aurora - is that light pollution or what? - and the faint green airglow on top of the bronze-colored layer. Note the Pleiades almost lost in the glare of the Moon. And yes, Johnny, those reddish lights on the Earth are cities.

What is that blue star at left that has been labeled "Starlight"? Is it Bellatrix? I believe that the red star between the labeled blue star and the Pleiades is Aldebaran, and Aldebaran is located about square in the middle between the Pleiades and Bellatrix.

Ann