Astrophotographer Spots Spacewalking Astronauts From the Ground (space.com) 35
InfiniteZero shares a report from Space.com: Last Wednesday (March 23), NASA astronaut Raja Chari and the European Space Agency's Matthias Maurer spent nearly seven hours outside the International Space Station, performing a variety of maintenance work. Amazingly, astrophotographer Sebastian Voltmer managed to capture a snapshot of the spacewalk action from the ground -- and from Maurer's hometown of Sankt Wendel, Germany, no less. "I feel like I just made a once-in-a-lifetime image," Voltmer wrote at SpaceWeather.com, which featured the photo in its online gallery.
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what ground - earth? moon? Jupiter?
or did you mean "earth" is the ground this happened?
They meant the bare copper wire in the electrical box ... it was a *really* odd camera angle.
Re: from the ground? (Score:2)
These are fascinating times.
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It's called the earth in English -- but the ground in American
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Alas, many Americans would call it "the floor."
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While trying to be symantically and technically correct for a joke can be fun sometimes, you've completely missed the mark here. Assuming this is suppose to be a joke and that you aren't being serious...
I'm really having a tough time trying to work out why "the ground" could possible refer to anything else but the ground we stand on. I've never ever heard of "the ground" being used to reference anything else, not even when we had astronauts on the moon.
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The ground associated with Sankt Wendel, Germany, which was mentioned in the same frigging sentence.
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Kinda cool (Score:2)
But has NASA issued a DMCA takedown notice yet?
Takedown notice (Score:2)
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Oh, it's going to happen, and probably sooner than we think.
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why would they, when they can just issue an NFT?
Original post (Score:5, Informative)
I'm a fan of linking to the original source so that kudos can be given to the right person.
So here's the original Twitter post with this image: https://twitter.com/SeVoSpace/... [twitter.com]
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thank you, much better image there too
Those space suits are designed to be as reflective as possible, to minimize heating of the astronaut from direct sun exposure, so that makes them much easier to spot by telescope. But still, that's a pretty small feature, and that thing's streaking across the sky at that zoom level. He must have some pretty good tracking software and hardware on that telescope.
I have a hard enough time getting good close-up pictures of the MOON during an eclipse without motion-trackin
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Voltmer used a Celestron 11-inch EdgeHD telescope on a GM2000 HPS mount [10micron.com] and an ASI290 planetary camera to get the shot
Yes, I am sure he had tracking software with the elements of the ISS orbit to drive the mount.
This is a very high precision ($16,000) mount that can track accurately without periodic error and does not require the use of a guide scope (often used by amateur astrophotographers to maintain tracking accuracy to compensate for drift). I suspect he was using "lucky imaging" where you take many frames and then select (and possibly combine) those that happen to low atmospheric distortion by random chance. Lucky im
Distance ? Camera resolution ? McFly ? (Score:1)
A nerd - or anyone with a hint of curiouslty - would want to know these things.
Slashdot purports to be for nerds.
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Camera resolution is 2.1 MP @ 1936 x 1096. Distance is nominally 400 km, but the ISS wanders around a lot.
Astrophotography cameras are more about light sensitivity than resolution. The resolution ultimately has much more to do with the optics in front of the camera. This was shot with a Celestron 11 inch Schmidt- Cassegrain telescope, which is native f/10.
As an aside, the best astrophotographers are all large men. Larger telescopes get heavy really quickly. Anyone can buy one of these (an equivalent sc
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And a good EQ mount for one of these is going to be pretty substantial too, unless he had it mounted on a pier. My 10" Dob is already a bit of a beast to handle (let the inappropriate telescope jokes fly now) by itself, although it's only an f/4.5.
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although it's only an f/4.5
Only f/4.5? I would think an f/4.5 lens is better than an f/10 lens for astrophotography. At that distance I wouldn't think that depth of field would be too much concern and for this kind of astrophotography you would probably benefit from the faster shutter speed you could get with an f/4.5 lens (less chance of movement induced blur).
Admittedly, I don't do astrophotography and am basing the above on "normal" photographic principles so maybe with astrophotography things are different.
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It's not about depth of field. It's about brightness, magnification, field of view, and off-axis distortion. Shorter focal lengths are brighter and ideal for dim, diffuse [slate.com] deep space objects. Larger apertures are always preferable, but for different reasons. For short focal length light buckets, the image from a fatter telescope will be brighter. For high magnification images, the resolution of a fatter telescope is finer.
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It's not about depth of field. It's about brightness
Basically what I wrote. 8^)
At the distances in question depth of field shouldn't be an issue and a larger aperture (smaller f-stop) gives you more light for a faster shutter speed (more light).
Focal length is a whole other kettle of fish. 8^)
Here's the photo, so you don't have to click thru (Score:5, Funny)
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Another tidbit (Score:2)
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Anyone who can make a living by spouting obviously false nonsense is probably a bit smarter than the average person. In exchange for having a reputation as a dummy, they essentially don't have to work for a living.
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Meanwhile ... (Score:2)