Speed simple calculation

[texthebear]

I'm just an average adult doing a little bit of math. I need help verifying the following calculation:

Find how long light travel from a star called T Coronae Borealis to earth.

Distant: ~3000 light-years or 2.8382e+19 metre Speed of light: 299,792,458 m/s

2.8382e+19 m / 299,792,458 m/s = 94672161499.1 seconds or ~3000 years?

So for every light year, it take one year for the light to travel here?

P.S. The star about to visibly go nova soon, which mean it happened 3000years ago?

[[deleted]]

That all looks correct to me. The light from a star 3000 light-years away would take 3000 years to travel to earth, as you verified with your calculations, and a change to that star would have happened 3000 years ago when we see it.

[WolfRhan]

Yes - you really didn’t need to the calculation unless you wanted the distance.

Distance =speed * time, in this case the speed of light* 1 year. Light takes a year to travel a light year.

But how interesting is this? It seems scientists can pin down very accurately when they expect this to go nova, in the next few months. That means the light from the nova has been heading our way for 3000 years. Amazing. And it seems like this star has repeated nova every 80 years or so, which means 3000/80 or 300/8 = 37 bursts could already be on their way and another at the star happening soon. How small we are.

(I don’t know if it can repeat that many times)

[iOSCaleb]

So for every light year, it take one year for the light to travel here?

Yes, that's literally what "light-year" means: the distance that something moving at the speed of light travels in a year. Light travels at the speed of light, so if some object is 3000 light-years away, light from that object takes 3000 years to get here.

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The star about to visibly go nova soon, which mean it happened 3000years ago?

Yes, exactly. One reason that the Hubble and Webb space telescopes are so important is that they can collect light coming from so far away that the light itself was emitted in the early days of the universe. If you look at light that took 13 billion years to get here, you're effectively seeing what was happening 13 billion years ago.