by alter-ego » Sat Jul 17, 2021 4:59 am
johnnydeep wrote: ↑Fri Jul 16, 2021 3:29 pm
VictorBorun wrote: ↑Fri Jul 16, 2021 5:29 am
how come that Mars is double-exposed like all the stars but one?
Love and War by Moonlight-.jpg
Well, you get an A for being observant, that's for sure! Here's something else in the same "one of these things is not like the others" category:
What's This Smear.JPG
Good catches of those images. I've done some quick visual estimates and simple calculations that support your faint streak
could be a satellite.
→ I estimate the image exposure time is close to 10 seconds, give or take
→ I estimate the streak length ~0.12°
→ I estimate the limiting magnitude at this elevation ~8.5 magnitude
For this to be a satellite, it must be in a higher orbit than LEO. The streak length is too short for an LEO satellite (LEO streak of the order 10°)
→ A very close candidate is a GPS satellite at 20,200km, traveling at 13,900km/hr.
In 10 seconds, the calculated streak length ~ 0.11°
I've not searched for any satellites that might be visible from this region or if any of these mid-orbit satellites are visible, and I don't know the expected magnitude. It may be coincidence, but a satellite is a logical candidate.
As far as the other anomalous spots go, they be artifacts from the camera, but I'm guessing they are not actual light sources in the sky.
[quote=johnnydeep post_id=315039 time=1626449375 user_id=132061]
[quote=VictorBorun post_id=315031 time=1626413397 user_id=145500]
how come that Mars is double-exposed like all the stars but one?
Love and War by Moonlight-.jpg
[/quote]
Well, you get an A for being observant, that's for sure! Here's something else in the same "one of these things is not like the others" category:
What's This Smear.JPG
[/quote]
Good catches of those images. I've done some quick visual estimates and simple calculations that support your faint streak [i]could be[/i] a satellite.
→ I estimate the image exposure time is close to 10 seconds, give or take
→ I estimate the streak length ~0.12°
→ I estimate the limiting magnitude at this elevation ~8.5 magnitude
For this to be a satellite, it must be in a higher orbit than LEO. The streak length is too short for an LEO satellite (LEO streak of the order 10°)
→ A very close candidate is a GPS satellite at 20,200km, traveling at 13,900km/hr. [b]In 10 seconds, the calculated streak length ~ 0.11°[/b]
I've not searched for any satellites that might be visible from this region or if any of these mid-orbit satellites are visible, and I don't know the expected magnitude. It may be coincidence, but a satellite is a logical candidate.
As far as the other anomalous spots go, they be artifacts from the camera, but I'm guessing they are not actual light sources in the sky.