Recent comments in /f/space

EmergeHolographic OP t1_j5iw1n7 wrote

It's more that there generally isn't a well fitting word for what I'm doing. "Stereoscopic" is the closest, though; "noting or pertaining to three-dimensional vision or any of various processes and devices for giving the illusion of depth from two-dimensional images or reproductions, as of a photograph or motion picture."

It accurately conveys the medium, viewing method and the intended subject, which is the symmetry. As long as I get those things across

−8

Decronym t1_j5iuj1s wrote

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:

|Fewer Letters|More Letters| |-------|---------|---| |ESA|European Space Agency| |LIGO|Laser Interferometer Gravitational-wave Observatory| |LISA|Laser Interferometer Space Antenna|


^(3 acronyms in this thread; )^(the most compressed thread commented on today)^( has 22 acronyms.)
^([Thread #8467 for this sub, first seen 23rd Jan 2023, 08:35]) ^[FAQ] ^([Full list]) ^[Contact] ^([Source code])

3

SpartanJack17 t1_j5ipf32 wrote

Hello u/Billy_bilo_, your submission "Theoretically if we could instantly send a strong-enough telescope to a location millions of lightyears away from Earth, would we be able to see into our past?" has been removed from r/space because:

  • Such questions should be asked in the "All space questions" thread stickied at the top of the sub.

Please read the rules in the sidebar and check r/space for duplicate submissions before posting. If you have any questions about this removal please message the r/space moderators. Thank you.

1

drdan82408a t1_j5ioz7y wrote

Sure, but there are a few problems with that.

  1. to see the earth from millions of light years away would require a telescope that is beyond the realm of imagination. The andromeda galaxy is about 2.5 million LY away, so think about resolving a single star in andromeda, and then think about resolving something much smaller in the glare of a star. But you did say a telescope strong enough, so….

  2. however many light years away you send the telescope, it will take that many years for the signal to return to earth. So if you sent the telescope to Andromeda 2.5 MLY from earth, you would get images back in 2.5 million years, of what would be then 5 million years ago.

  3. if there is intelligent life on earth in 2.5 million years; it will certainly be different than today. To give some perspective, that was when the first Homo habilis were differentiating from Australopithecus. I think it’s doubtful that our computers will be able to talk to each other when the signal arrives.

  4. similar to the problem in resolution of the telescope, keeping a radio signal coherent over that amount of space would be a heck of an engineering challenge and take a tremendous amount of energy.

2

Cannibeans t1_j5iocuq wrote

No. At 20 lightyears away, you'd need a telescope 1000x the size of the Earth for a single human to appear as a pixel, and even then you'd only be seeing 20 years into the past. This gets exponentially worse the further you go.

Millions of light-years away, there's not enough photons to collect. You'd need a telescope the size of several galaxies, made of material harvested from thousands of other galaxies, just to make out the planet.

0