The Astronomy Thread
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Guest, it's time once again for the massively important and exciting FoH Asshat Tournament!
Go here and give us your nominations!Who's been the biggest Asshat in the last year? Give us your worst ones!
Technically, "yet" needs quotes as well. "Now" is a concept relative to your own point as an observer in spacetime. Distance at lightspeed is certainly a useful approximation, but the deeper you dig the weirder time gets.
Relativity of simultaneity - Wikipedia
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Kirun
Buzzfeed Editor
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Isn't this somewhat of a semantics argument though? Like, I get that "now" is a different concept 650LY away, but nonetheless, their "now" would still occur 650LY "later" relative to our "now".Technically, "yet" needs quotes as well. "Now" is a concept relative to your own point as an observer in spacetime. Distance at lightspeed is certainly a useful approximation, but the deeper you dig the weirder time gets.
Relativity of simultaneity - Wikipedia
en.wikipedia.org
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Cad
scientia potentia est
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No because of time dilation, “now” 650LY away may not be 650 years ago depending on the observers speed, direction, etc. One observer traveling close to the speed of light may have observed the supernova 650LY away 10 years ago, and then flew into our space.
Space and time and “now” are sort of not concrete concepts as soon as you start talking about interstellar distances.
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Mudcrush Durtfeet
Hungry Ogre
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Only in a very broad sense. Time progresses (slightly) differently everywhere based on local spacetime curvature. There isn't a time you can point to in Betelguese's chronology that precisely lines up with 650 years ago in ours. Read the wiki link.
Blakkheim
Karazhan Raider
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Borzak
Bronze Baron of the Realm
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Scientists Have Calculated How Long It'll Take to Reach Distant Stars
Are we there yet?
Who will have the best shot at reaching and exploring a distant star? Pioneer 10 will swing within .231 parsecs the star system HIP 117795 in the Cassiopeia constellation in approximately 90,000 years. And how long before one of these spacecrafts is hijacked by the orbit of one of these stars? It’ll be about 1,000,000,000,000,000,000,000 years.
Brahma
Obi-Bro Kenobi-X
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Since everyone is doing a "Best Of The Decade" thing...Here's my nomination for best in astronomy.
www.sciencealert.com
It's Official: Astronomers Just Unveiled The First-Ever Direct Image of a Black Hole
No.
www.sciencealert.com
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iannis
Musty Nester
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Yeah, just like there is no universal grid and all objects are relative to other objects (there is no universal {0,0,0}) there is no universal now.
As a concept at interstellar distances it's not entirely meaningful. That follows from the observation that the transfer of information is not instantaneous.
We can take a telescope and peer into the furthest reaches of space possible for us to do that. What we see are mis shapen galaxies, we've decided that they're young galaxies, we understand this to be a historical record. All of that is consistent with the idea of the speed of light.
Now if that's what it is, how can that exist contemporaneously with us, the descendants of that process looking back into our own record? If we picked one mis shapen blob and pointed a space ship at it and traveled at the speed of light to it, would we ever get there? Ignore the expansion of space, we can account for that in our speed too with this magic. And what about the stuff past that?
The only possible way that it can exist is to discard this notion of the eternal, present, "now". And if it doesn't exist... well, how the fuck can we see it? It does exist in some manner.
As a concept at interstellar distances it's not entirely meaningful. That follows from the observation that the transfer of information is not instantaneous.
We can take a telescope and peer into the furthest reaches of space possible for us to do that. What we see are mis shapen galaxies, we've decided that they're young galaxies, we understand this to be a historical record. All of that is consistent with the idea of the speed of light.
Now if that's what it is, how can that exist contemporaneously with us, the descendants of that process looking back into our own record? If we picked one mis shapen blob and pointed a space ship at it and traveled at the speed of light to it, would we ever get there? Ignore the expansion of space, we can account for that in our speed too with this magic. And what about the stuff past that?
The only possible way that it can exist is to discard this notion of the eternal, present, "now". And if it doesn't exist... well, how the fuck can we see it? It does exist in some manner.
Aaron
Goonsquad Officer
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He's not the hero we need, but he is the hero we want.
Godspeed, little-dick-rocketman. Godspeed
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Big Phoenix
Pronouns: zie/zhem/zer
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