Astronomy Question

[LeavesOfGrass]

Hypothetically speaking, if I were positioned on a distant planet, some 10 million light years from earth, and was equipped with a telescope thrice as powerful as, let's say, the Hubble Telescope, could the below happen?

Let's assume that this telescope is so powerful that it could magnify to a degree that would let me identify a tree on planet earth. Now, since light travels at such an odd pace, could I possibly train my scope on earth and catch a glimpse of a prehistoric creature, or actually view terra firma in its early stages; possibly pre-moon? Just curious.

[JuniperWoolf]

That's a pretty cool thought. Like, if we had the ability and resources to travel faster than the speed of light, could we out-run the light and make it to such a distance that we could literally look into the earth's past? I don't see why not.

[OrphanPip]

I would assume you would see the Earth as it was 10 million years ago, if you were 10 million light years away. You would be able to see some extinct mammals, birds, and plants maybe .

(In reality though, light reflecting from the surface of a planet in such a way that discernible images are created is highly unlikely, I'm not a physicist though, so maybe it's possible to see something. You have to remember that planets don't emit light, so when you see them in telescopes what you're seeing is the light from stars bouncing off them. How we detect planets now is the distortion of light from stars that is created by the gravity of a planet.)

[blazeofglory]

Many of the questions raised here can be found in science fictions only

[applepie]

I imagine you would be seeing a very different Earth. Hmmmm, extinct animals and plants. Imagine, no lights and no people running around with cars. Now you have me wishing I could see it

[SleepyWitch]

I guess you could see those creatures, if you were able to beam to that planet right now (except for what Pip said). But if you had to travel there first, it would take a lot longer than 10 Million light years to get there and then you'd only see Earth as it is now or after you left, because the time it takes you to travel and the time it takes light to travel cancel each other out.

[ClaesGefvenberg]

Orphan and Sleepy said it:

Being positioned 10 Million light years away you would see what whatever happened 10 Million years ago. Getting to that position is an entirely different matter, of course.

/Claes

[billl]

What is interesting to me, is to imagine a triangle, where one corner is opposite a particular side "a". Now, if that corner is many many light years away, then the side "a" could receive only a slight amount of iight from that distant "corner" if that corner were a bright sort of light (e.g. a star).

I understand that VERY distant stars are invisible to the naked eye. However, it is still a bit amazing that two people, standing next to each other, a mere 40 cm apart, would both recognize the arrival of photons from some distant star, and that this agreement about the existence of the said star should continue as both observers wandered about, criss-crossing each other, and always receiving some detectable share of photons from that distant star. Really, this seems to indicate that a star that is perhaps 3 or 12 or more light-years away is sending out photons IN EVERY DIRECTION in SUCH A DENSITY that people sitin side-by-side on Earth (many light-years away, but just 20-40cm apart) would each receive enough photons to register a star out there in the galaxy, and that a slight shift of perhaps 12 inches to the side would keep oneself in the field of dispersed but visible photons, from such a vast distance.

Anyhow, this is a wild idea that I heard on a podcast once before, and while it might not disprove anything, I think it certainly is enough to make one reconsider just HOW full of photons our "empty" cosmos must be...

[LeavesOfGrass]

It's hard to wrap your mind around it. I'm a bit disgruntled that our current President cut funds directed towards NASA, but I suspect that this will be reversed soon enough. Of course, space travel is now becoming such a private matter, i.e. Richard Branson, that we may see progress in leaps and bounds in the next decade.

But ever more puzzling is the mystery of dark matter, or what was once termed ether. It seems that scientists are on the brink of confirming its existence.

[SleepyWitch]

It's hard to wrap your mind around it. I'm a bit disgruntled that our current President cut funds directed towards NASA, but I suspect that this will be reversed soon enough.

I'm in two minds about that. On the one hand, I think exploring space is all very exciting etc. but on the other hand it seems like a waste of money while there are much more urgent problems on earth.
The other day I read an article about terra-forming Mars in National Geographic. They explored whether it could be done and showed how Mars can be terra-formed step-by-step over 1,000 years. Finally it would look very earth-like but people would still have to live in domes and wear scuba masks outside because it would still be too cold and there wouldn't be enough oxygen. Plus, the newly created atmosphere of Mars would evaporate again even before Earth becomes uninhabitable.
Of course, no one is planning to terra-form Mars right now, but some scientists say it could be done given a vast budget. Now, the art-work in that article was really beautiful so it all looked a bit like sci-fi/fantasy and as very nice. But seriously, how daft would it be to slog away at terra-forming only so that people can live in domes and then it was all in vain in the end anyway? Plus, there is no agency that could make that sort of commitment for 1,000 years? But let's imagine the finance aspect was sorted out and they really did it. What if something went wrong and people were stuck in those domes and could never get off Mars, or ould die a slow death there? What a waste. Or what if after 500 years something came up and they realized they can't do it after all?

[OrphanPip]

NASA scientist like to habitually complain about funding cuts. The director of the Mars Rover missions gave a lecture to one of my classes at university and he spent half of it complaining about Bush (who was president at the time) cutting funding to Mars programs to concentrate on the moon. Funding has been an uphill battle for them since the Apollo missions ended. A lot of great technology has been developed by NASA directly and indirectly, like tang and velcro, you get other useful stuff besides the intended results of the space missions themselves. As a microbiologist, a lot of great research got to get done on bacteria in extreme regions that would otherwise have been ignored. Sure, nothing practical came of that, but we expanded humanity's knowledge of the world we live in.