Other Satellites

[Spherical Cow]

After many tries, I finally got a video of the oldest man-made satellite still in orbit, Vanguard 1. Launched in 1958, it was only the 4th successful satellite to orbit, after Sputniks 1 and 2, and Explorer 1, all of which have decayed out of orbit. Its spherical, and only 16 cm in diameter (6.3 inches), and at this time on this pass it was about 795 km away (493 miles). A 6-inch target at almost 500 miles.

I’m assembling a system to do asteroid occultation timing, and used that with its occultation video camera (30 FPS) at max gain on a 235mm scope. The satellite passed through the field of view in about ½ sec, so it shows up on only 16 frames. Stacking too many frames seems to just average out the satellite, instead of enhancing it, so below is a combination of just 8 frames, with the satellite as a fuzzy streak coming up from the bottom of the image. The numbers at the bottom are from a GPS unit that puts exact GPS time on each frame for the occultation timing. From calculations on CalSky.com, it should have passed almost dead center through this field of view at 02:18:41.0 (UTC). The first frame in this group was at 02:18:40.7494 . It was dead-on accurate time-wise, but shifted about 5 arc-minutes to the right, and almost occulted the bright star here.

Anyway, the system seems to be working well, so I’m ready to start getting useful asteroid occultation timing data finally. And I've seen a 62 year old 6-inch sphere at almost 500 miles. Pretty neat.

Norm

[xilman]

Originally Posted by Spherical Cow

After many tries, I finally got a video of the oldest man-made satellite still in orbit, Vanguard 1. Launched in 1958, it was only the 4th successful satellite to orbit, after Sputniks 1 and 2, and Explorer 1, all of which have decayed out of orbit. Its spherical, and only 16 cm in diameter (6.3 inches), and at this time on this pass it was about 795 km away (493 miles). A 6-inch target at almost 500 miles.

I’m assembling a system to do asteroid occultation timing, and used that with its occultation video camera (30 FPS) at max gain on a 235mm scope. The satellite passed through the field of view in about ½ sec, so it shows up on only 16 frames. Stacking too many frames seems to just average out the satellite, instead of enhancing it, so below is a combination of just 8 frames, with the satellite as a fuzzy streak coming up from the bottom of the image. The numbers at the bottom are from a GPS unit that puts exact GPS time on each frame for the occultation timing. From calculations on CalSky.com, it should have passed almost dead center through this field of view at 02:18:41.0 (UTC). The first frame in this group was at 02:18:40.7494 . It was dead-on accurate time-wise, but shifted about 5 arc-minutes to the right, and almost occulted the bright star here.

Anyway, the system seems to be working well, so I’m ready to start getting useful asteroid occultation timing data finally. And I've seen a 62 year old 6-inch sphere at almost 500 miles. Pretty neat.

Norm

Nice.

You should stack on the satellite, not the stars, if you want a clear view. I can try and dig up some references to relevant software if you wish. I have an exceedingly crude implementation which has been used to stack Jovian satellites.

[Spherical Cow]

Originally Posted by xilman

Nice.

You should stack on the satellite, not the stars, if you want a clear view. I can try and dig up some references to relevant software if you wish. I have an exceedingly crude implementation which has been used to stack Jovian satellites.

Ah- Good idea; thanks for that. I think I can do that with what I've got.

Norm