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Can You Find the Comet?

apod.nasa.gov

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Re: Can You Find the Comet?

#91

Post by adev_ »

mgfist wrote: post #56
adrian_b wrote: post #16

Earlier quoted context omitted.

Unfortunately, that seems to be the only solution. However, it has serious disadvantages. It will exclude the poorer from astronomical research, except within the limits enabled by whatever cooperation the richer will be willing to do with them. For the richer, that will make astronomical research much more expensive. When even USA, who claims to be the richest country, cuts a lot of the scientific funding, this make…

I get what you're saying, but poor people want cheap internet/phone connectivity. They can't afford telescopes anyways. And starlink (and the like) have more uses beyond good remote connectivity. They're a big reason why Ukraine didn't lose to Russia. They're also a potential avenue for people in oppressed nations to talk to the rest of the world (eg: Iran has a death penalty for starlink usage to counter this point)…

> I get what you're saying, but poor people want cheap internet/phone connectivity.

Nope. Starlink is not a tool for poor people. It's first and foremost a tool for middle class living in rural area with poor connectivity.

As a comparison, it is estimated to that there is around 198M people in Nigeria with a Mobile phone connectivity. Compared around 67K Starlink users.

Mobile being around 2-3x cheaper than Starlink there (even without considering the hardware), it remains an upper middle class privilege.

Re: Can You Find the Comet?

#92

Post by NooneAtAll3 »

advisedwang wrote: post #89
mlmonkey wrote: post #83

Why doesn't the comet "streak" also, given the Earth's rotation? 10 minutes is a long enough window to have an appreciable impact on the comet's image. Or is it the case that the telescope is stabilized to the Earth's rotation?

Low earth orbit satellites orbit about once per 90 minutes, so in 10 minutes they go about 40 degrees across the sky. The comet is not even orbiting the earth, it's essentially fixed in the sky. The earth only rotates about 2.5 degrees in 10 minutes. So the satellites streak is 16 times longer than the comets.

40 degrees around Earth (central angle)

but it increases to much more when you are much closer to the arc

Re: Can You Find the Comet?

#93

Post by saddat »

1970-01-01 wrote: post #42

I, a taxpayer, would rather have a cellphone signal in a remote location than lots of amazing pictures of a comet. And I just don't see a solution or compromise that could work. The utility of neat picture vs full cell signal in a Montana canyon cannot be won by taking more pictures and showing me the problem. I made my decision already.

I , as a citicen, would like that research will figure out the origins of space and time

Re: Can You Find the Comet?

#94

Post by max-m »

mlmonkey wrote: post #83

Why doesn't the comet "streak" also, given the Earth's rotation? 10 minutes is a long enough window to have an appreciable impact on the comet's image. Or is it the case that the telescope is stabilized to the Earth's rotation?

https://www.facebook.com/groups/Nachtfotografie/posts/264063... Here is the original photo description in German. See also my other comment in this thread. But the tl;dr is that this was a stack of 153 four-second exposures with some gaps in the timelime when the camera took its time to save between exposures.

Re: Can You Find the Comet?

#95

Post by estimator7292 »

1970-01-01 wrote: post #42

I, a taxpayer, would rather have a cellphone signal in a remote location than lots of amazing pictures of a comet. And I just don't see a solution or compromise that could work. The utility of neat picture vs full cell signal in a Montana canyon cannot be won by taking more pictures and showing me the problem. I made my decision already.

"As an American, I believe that my personal convenience outweigh the needs and desires of literally every other person on the entire planet"

Re: Can You Find the Comet?

#96

Post by pta2002 »

pta2002 wrote: post #40
albert_e wrote: post #15

Why are satellite trails not continuous lines Is the camera exposure taking a few seconds of break between takes that get stacked later with some "missing" moments in between?

Probably exactly that. If you take a single 10 minute exposure (or really, anything more than a few seconds) you'll get noticeable star trails if you don't put your camera on a rotating mount. Stacking multiple exposures also has other nice benefits such as noise canceling itself out and being able to remove satellite trails. Last time I did astrophotography was a few years ago, before Starlink made the problem consi…

Update: I was wrong, check max-m's sibling comment! The satellites just move really fast across the camera because they're in LEO, so they can traverse rather large distances before there's a new exposure and a small gap.

Re: Can You Find the Comet?

#97

Post by dangond »

advisedwang wrote: post #89
mlmonkey wrote: post #83

Why doesn't the comet "streak" also, given the Earth's rotation? 10 minutes is a long enough window to have an appreciable impact on the comet's image. Or is it the case that the telescope is stabilized to the Earth's rotation?

Low earth orbit satellites orbit about once per 90 minutes, so in 10 minutes they go about 40 degrees across the sky. The comet is not even orbiting the earth, it's essentially fixed in the sky. The earth only rotates about 2.5 degrees in 10 minutes. So the satellites streak is 16 times longer than the comets.

Given that the moon is about 0.5 degrees in diameter from Earth, shouldn't we expect to see the stars and comet much more blurred than they are here though? Or the ground if it's stabilized against the rotation?

Re: Can You Find the Comet?

#98

Post by zamadatix »

moffkalast wrote: post #54
bluGill wrote: post #37

Earlier quoted context omitted.

I doubt they will elevate their orbit by enough to be a problem. Some bits will come down in hours, some will come down in a year - even in the worst case where it takes out everything in low earth orbit in 5 years everything will be clear and we can start over. Higher orbits are the real worry, even the things slowed down mostly stay in orbit for centuries - but higher orbits are mostly a lot higher.

Don't be so sure: https://stuffin-space.vader.zone/ The Iridium-Kosmos collision fragments have been up there since 2009, and that's a massive spray of junk just from one disintegration in LEO.

"LEO" is a big place, those satellites collided ~1.5x higher than e.g. the maximum Starlink altitude and the debris lifetime relationship is not a linear one.

Re: Can You Find the Comet?

#100

Post by renerick »

AntiUSAbah wrote: post #65

We do not need Starlink! It only provides service to 9 Million! People We are a planet with 8 Billion People. Do i want cheap and reliable internet everywhere and perhaps work remote? Yes. Should someone like Musk destroy our look into space for just me and my use case? No.

How many hours are spent looking at the sky compared to Starlink usage?
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