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Can You Find the Comet?

apod.nasa.gov

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Re: Can You Find the Comet?

#21

Post by inquirerGeneral »

adrian_b wrote: post #16
ultratalk wrote: post #12

Earlier quoted context omitted.

Opinion: We need to move our astronomical observation equipment off of Earth and onto other bodies, especially radio astronomy, which, unlike telescopes that operate in other wavelengths, is still affected by Earth's emissions in LEO/near-Earth space. We should put a radio telescope on the far side of the moon [0] to benefit from the thousands of kilometers of lunar material separating Earth's emissions from telescop…

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…

[dead]

Re: Can You Find the Comet?

#22

Post by Aboutplants »

ultratalk wrote: post #12
adev_ wrote: post #11

Earlier quoted context omitted.

And this is just the visible spectrum. The situation is one order of magnitude worst in radio-astronomy. It is fair to state that satellite constellations will certainly be the main obstacle to multiple major scientific discoveries in the next decade.

Opinion: We need to move our astronomical observation equipment off of Earth and onto other bodies, especially radio astronomy, which, unlike telescopes that operate in other wavelengths, is still affected by Earth's emissions in LEO/near-Earth space. We should put a radio telescope on the far side of the moon [0] to benefit from the thousands of kilometers of lunar material separating Earth's emissions from telescop…

Any chance of CubeSat style of telescopes at some point?

Re: Can You Find the Comet?

#23

Post by iso1631 »

ultratalk wrote: post #12
adev_ wrote: post #11

Earlier quoted context omitted.

And this is just the visible spectrum. The situation is one order of magnitude worst in radio-astronomy. It is fair to state that satellite constellations will certainly be the main obstacle to multiple major scientific discoveries in the next decade.

Opinion: We need to move our astronomical observation equipment off of Earth and onto other bodies, especially radio astronomy, which, unlike telescopes that operate in other wavelengths, is still affected by Earth's emissions in LEO/near-Earth space. We should put a radio telescope on the far side of the moon [0] to benefit from the thousands of kilometers of lunar material separating Earth's emissions from telescop…

> . We should put a radio telescope on the far side of the moon [0] to benefit from the thousands of kilometers of lunar material separating Earth's emissions from telescopes.

Do you really think a starlink style installation won't be put in orbit of the moon before such a telescope could be funded?

Re: Can You Find the Comet?

#24

Post by voidUpdate »

ultratalk wrote: post #20
maxnoe wrote: post #14

Earlier quoted context omitted.

Our telescopes actually need the (or at least an) atmosphere to function. There are some classes of observatories, which you cannot build in space but which are still affected by satellites to some degree.

> Our telescopes actually need the (or at least an) atmosphere to function. What about Hubble, Chandra, Spitzer, JWST, etc? As of my understanding, the only reason we haven't built radio and and other long-wave telescopes in space is because of their impractical size preventing them from being deployed in orbit. > There are some classes of observatories, which you cannot build in space but which are still affected by…

I believe we haven't built radio telescopes in space because we don't need to, and building them in space would be a lot more expensive.

https://commons.wikimedia.org/wiki/File:Atmospheric_electrom...

This shows that wavelengths between ~10cm and ~10m are largely unaffected by the atmosphere, so you wouldn't gain much from putting receivers of those wavelengths in space. Spitzer and JWST (IR), and Chandra (x-ray) operate in bands that are generally blocked by the atmosphere, and Hubble gets better images than a similarly sized earth-based telescope because of the atmospheric distortion (stars don't "twinkle" when you're in space), however there are still earth-based visible light telescopes because you can more easily build a massive one on earth than in space

Re: Can You Find the Comet?

#25

Post by pedvide »

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?

I've taken long exposures using film (analog, so no stacking or any other funny business) and saw the same thing. I always thought they were planes but now it seems they may have been satellites. I'm curious if someone knows why this happens

Re: Can You Find the Comet?

#27

Post by mark-r »

originalvichy wrote: post #5

I fear this is only the start of it. A minimum of 3-4 constellations more will probably be launched in the near future (Russia, China, EU). Their obvious dual-use nature makes them tempting, and a military target if a large conflict will take place in the near future. I hope their lower orbit will help any space junk burn up fast.

If you blow up a satellite, half of it will end up going slower and half will go faster. The slower bits will probably burn up nicely, but the faster bits will just elevate their orbit.

Re: Can You Find the Comet?

#28

Post by mark-r »

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?

I'm not aware of a digital camera that can take a 10 minute continuous exposure, but maybe there are special astronomy cameras that can?

Re: Can You Find the Comet?

#29

Post by adev_ »

iso1631 wrote: post #23
ultratalk wrote: post #12

Earlier quoted context omitted.

Opinion: We need to move our astronomical observation equipment off of Earth and onto other bodies, especially radio astronomy, which, unlike telescopes that operate in other wavelengths, is still affected by Earth's emissions in LEO/near-Earth space. We should put a radio telescope on the far side of the moon [0] to benefit from the thousands of kilometers of lunar material separating Earth's emissions from telescop…

> . We should put a radio telescope on the far side of the moon [0] to benefit from the thousands of kilometers of lunar material separating Earth's emissions from telescopes. Do you really think a starlink style installation won't be put in orbit of the moon before such a telescope could be funded?

> Do you really think a starlink style installation won't be put in orbit of the moon before such a telescope could be funded?

There are ITUs rules that forbid that and the far side of the moon is declared as radio quiet.

Re: Can You Find the Comet?

#30

Post by rcxdude »

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?

Maybe, but also a lot of satellites rotate and so their brightness changes over time.
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