this thing does spectroscopy so it just measures the wavelength of the light that comes in, so we got some light at that wavelength, a little at that wavelength, a lot at that one etc. and from that you can do fuckloads of physics to learn insane amounts of stuff about something located far away. The specific thing about this telescope is the new technique it uses, normally we take in a bunch of light on a big bowl and run it through band pass filters (think complicated prisms, as in a physical thing that stands in the way and splits light) and then we get the different wavelengths.
This thing has a different method of doing it, it manually controls thousands of individual little⌠âreceiversâ that are like open ends of optic fibre cables, that split the light after it comes in. This setup could easily be constructed previously in some set and locked configuration, but when you do observations you constantly have to reset, calibrate, shift, correct, tilt, maintain etc. the instrument which is extremely sensitive business, and this thing can be âreconfiguredâ manually very quickly (it has moving parts or however you explain it in English) so it can actually be used for observations. This gives sweet accuracy and so forth, and the rest of the instrument is also top notch, so in the end it kind of⌠magnifies better.
Then again Iâm a geek who is thoroughly entertained by a two hour lecture on Cosmology/Astrobiology, and would prefer that to 99% of what is shown on tv
We know Universe is expanding, and for all we know our milky way is not on the same coordinates as it was 10 years ago; any time traveller who travels back in time with same x,y,z coordinates will end up stranded in space or at very least inside a wall.
first of all youâd if you can do time travel Iâm sure they figured out that time space is coupled and youâd need four-vectors (t,x,y,z) not just x,y,z to go some place in spacetime. there, time is just a coordinate in a 4d space and you canât talk about a point in space without the time coordinate there included. you simply need all 4 to state your position, and you donât have that problem.
for the expansion of the universe, when you set your x,y,z coordinates the expansion is rather stretching the universe so it would stretch the metric you use with time as well for things that are not gravitationally bound, like inside the galaxy. I think theyâd be ok with a transformation of coordinates there.
I believe in these time travelers, I think theyâd get it right.
