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[Madman198237]

They're not some compact thing, they huge. Galaxy-sized. in fact, they were probably the precursors to modern galaxies.

Quasars top out at around 10⁶ AU in diameter, which is about 1/19th the diameter of even the smallest dwarf galaxies and about 1/2000th the diameter of the average 10⁴-parsec galaxy. It's kind of lazy to say they're "galaxy-sized"

More accurately they're brighter than an entire galaxy, not sure how much brighter off the top of my head. They're visually "larger than" / "the same size as" than the galaxy they're in due mostly to the way our detection systems (both eyes and telescopes) function.

[Max™]

They're not some compact thing, they huge. Galaxy-sized. in fact, they were probably the precursors to modern galaxies.

Quasars top out at around 10⁶ AU in diameter, which is about 1/19th the diameter of even the smallest dwarf galaxies and about 1/2000th the diameter of the average 10⁴-parsec galaxy. It's kind of lazy to say they're "galaxy-sized"

More accurately they're brighter than an entire galaxy, not sure how much brighter off the top of my head. They're visually "larger than" / "the same size as" than the galaxy they're in due mostly to the way our detection systems (both eyes and telescopes) function.

Last time I checked A GRB can be brighter instantaneously, this one was 10⁵⁴ ergs~ or so: https://en.wikipedia.org/wiki/GRB_080916C while this one here was less energetic it happened to be a little closer and aimed exactly at us so it was VISIBLE TO THE NAKED EYE AT THAT DISTANCE, and if you put it where the sun is (abs mag -27) it would have been unbelievably brighter (abs mag -67!!!!) though they don't specify the energy, just noting that it's got a lookback time of ~7.5 billion years vs 12.2 billion years for the other: https://en.wikipedia.org/wiki/GRB_080319B, but these tend to be very brief events, and brightness can mean lots of things. If you're looking at it as energy over time, or power, then a GRB is a spike and gone, while a quasar in an active state can throw out GRB levels of power for thousands or millions of years.

[GPeter]

Ok, I need help with something here.

I was watching Interstellar (such a wonderful movie). And something caught my attention, when they were talking about the older mission, they said that they sent 3 scientists to 3 different planets. And overall, spent 50 years receiving signal and information from them (At least that's what I understand, there could be a problem with the dubbing as I watched it in Portuguese), but when our people arrive at the water planet, they state that "every hour in here means 7 years on earth" and thus, the scientist who got there, was there for maybe a couple of hours. Question is: How did earth receive 50 years worth of signal and info, if the scientists had such gravity distortions, in which one of the scientists didn't even have a day in his planet?

If you can answer this, you made my day, thank you.

[Max™]

Just sounds like time dilation mixed with handwavium? Never seen the movie, but the basic trimmed down answer is that time is another direction you are moving around in, besides the three you think of as being directions (centered on you, up/down, left/right, forward/backward, future/past) and there is a limit to how much you can move along any of those directions . If you speed up enough along a spatial direction it reduces how far you move along the temporal direction, so your local passage of time is reduced and you end up experiencing less time than your buddy who stayed at home while you zipped around across the galaxy. When you return home he's been dead for 150 years and one of his great great grandkids or some shit is there to greet you, though it's only been a couple of years from your perspective.

[GPeter]

Just sounds like time dilation mixed with handwavium? Never seen the movie, but the basic trimmed down answer is that time is another direction you are moving around in, besides the three you think of as being directions (centered on you, up/down, left/right, forward/backward, future/past) and there is a limit to how much you can move along any of those directions . If you speed up enough along a spatial direction it reduces how far you move along the temporal direction, so your local passage of time is reduced and you end up experiencing less time than your buddy who stayed at home while you zipped around across the galaxy. When you return home he's been dead for 150 years and one of his great great grandkids or some shit is there to greet you, though it's only been a couple of years from your perspective.

Yes, I do know that. My doubt is: The scientists at Earth, stated that they spent 50 years receiving signals and info gathered by the scientists on the planets. Now think about it, how much information would you gather in 50 years? A lot, right? So Earth knows a lot about the planets outside, but the thing is, it passed 50 years for people on earth, but mere days for the scientists on the planets. The scientists did not spend 50 years gathering info, so how did earth receive 50 years worth of data?

[Trekkin]

Yes, I do know that. My doubt is: The scientists at Earth, stated that they spent 50 years receiving signals and info gathered by the scientists on the planets. Now think about it, how much information would you gather in 50 years? A lot, right? So Earth knows a lot about the planets outside, but the thing is, it passed 50 years for people on earth, but mere days for the scientists on the planets. The scientists did not spend 50 years gathering info, so how did earth receive 50 years worth of data?

They didn't. They received a few hours of information as transmitted by the scientists, redshifted 61320-fold by gravitational time dilation owing to the nearby black hole.

[GPeter]

So basically they received a few hours of data, but ir arrived so slowly that it took 50 years to finish?

[Trekkin]

Exactly. They may have gotten more from a longer range, though; the strength of the dilation is inversely proportional to the distance to the massive object. (I haven't seen the film either.)

So if they leave what I'm assuming is a wormhole and fly straight down to the planet, transmitting all the while, you'd get long-range imaging in real time, with the observed dilation increasing as they got closer until it reached the aforementioned Lorentz factor on the surface.

[GPeter]

Well, thank you. But now my life has no more meaning.

[Il Palazzo]

Hey, don't be like that. Your life never had any meaning in the first place!

[GPeter]

Hey, don't be like that. Your life never had any meaning in the first place!

My most sincere thank you, and also... I'm sigging this

[Dorsidwarf]

I thought the people on earth didnt have data about the planets because they could only get a plain “still here” signal through the wormhole or something plot-based

[GPeter]

I thought the people on earth didnt have data about the planets because they could only get a plain “still here” signal through the wormhole or something plot-based

The paradox would continue, because then, earth received 50 years of "still-here" signals, while acctually, only a few days of signal has acctually been sent.

[Starver]

It's been a while since I saw it (when it came out), but I think it was a basic confirmation signal. They knew they couldn't get high bandwidth, they may even have had a mediating probe receive the (instantaneous-but-drawn-out) planetary signal, deal with its temporal issues and further help to extend its range back to Earth by acting as a latched relay.

IRL, the Voyager craft are working at around 160baud, currently, though they may have been faster during the Saturn encounter, apparently the location of this end of the wormhole. There's strangeness in passage through the wormhole, then the issues of travel from the other end. It is conceivable that even with current/near-future improvements to probe/spacecraft communications, the far end (and middle) of the outreach is already problematic, before the extreme doppler-esque slowdown.

If a full-handshaking mode could be established, then status updates might be prompted for (even if it takes a while), but I imagine the inflexibility of the transmitter (may only be able to ramp up its frequency so far, possibly only to the limits of the sending circuit, requiring the earth receiver/relay to adjust down to the ultra-low frequency it still would become) means that it may have been designed to be more UDPish than TCPish in its protocol, given how abnormally latency-tolerant it needs to be.


(I'd tell you a joke about UDP, but I'm not sure you'd get it.)

[LordBaal]

I thought the people on earth didnt have data about the planets because they could only get a plain “still here” signal through the wormhole or something plot-based

The paradox would continue, because then, earth received 50 years of "still-here" signals, while acctually, only a few days of signal has acctually been sent.

Didn't saw the movie, but i would guess the speed of the signal was distorted by the wormhole too.

Imagine you are sending me as bluray copy of Interstellar to me here via a file host(the wormhole), your upload speed is 1gbps thanks to google fiber, so you are done in a few minutes. On my side, with a 256kbps I'll have to spend days/weeks down loading it.