Posted on 01/26/2016 2:19:03 PM PST by BenLurkin
Don’t you think that they meant “nearest star other than our own” ?
Come on, you can’t tell me you don’t know what they mean.
Probably.
That demonstrates one of the many benefits of writing clearly.
thanks. it seems so much more exciting on Star Trek :)
Thank you.
Longer than that. Besides our Sun, the nearest star in Proxima Centauri. It’s about 6 light years from Earth. A single light year, the distance light travels in a vacuum is about 9 trillion miles. So 6 time 9 trillion is 54 trillion miles. You might want to take along a few good books and some DVDs.
+1 Saved me the trouble of pointing that out.
I have found that one of the best ways to really get a feel for the sheer size of the universe is to play around with a program called Celestia. There are versions available for Mac, Linux and Windoze.
The program allows you to fly areound the universe at whatever speed you like. It is an awesome program. Try flying around the solar system at ‘just’ the speed of light. It takes foever to get anywhere.
Then make tracks to alpha centauri while increasing your speed to a mind-blowing 30 or so AU per second, which means you are travelling at a speed that will blow past pluto onece a second. You’d think you are really hauling ass, but even at ludicrous spped, you’re not going to get there any time in the next few days.
Anyone in thread can explain like I’m five: If ship is traveling at speed of light, could some light based “radar” bounce off something in ships path, and return echo, faster than ship itself meeting said obstacle?
Hope I formed question clearly enough..
Sounds interesting. I’ll check it out.
Until we discover some way around relativity, it just ain’t going to happen. A trip to even the closest star with a tiny unmanned probe would take decades. Anything bigger, or with people on board, would take generations, if it were even possible.
Ion drives are highly efficient, in terms of the thrust you get for the weight of propellant you carry, but they are also extremely low powered. That’s why it took so long.
The Norks have already been there. (snicker)
-PJ
No, Sol is the nearest star, but we usually just call it the sun.
Think again - Sol, usually called the sun, is the “nearest star”.
“If ship is traveling at speed of light, could some light based âradarâ bounce off something in ships path, and return echo, faster than ship itself meeting said obstacle?”
No, the maximum speed of light (in a vacuum) is invariant, that is one of the basic rules of relativity. What this means is that, if you were on a spaceship traveling at the speed of light, and you turn on the headlights (or the radar beam in your example), the beam wouldn’t go anywhere.
When we think of physical objects, like standing on a moving train and throwing a ball forward, we have to add the velocity of the train and the ball together to get the total velocity. With light, it just doesn’t work that way. It has a maximum speed, and it can never travel faster than that, period.
Now, the whole question really is academic, because if you were traveling on a ship at the speed of light, time would stop. So you couldn’t possibly turn on the radar or headlights, because you wouldn’t be able to move, or think, or anything else. You’d be frozen in time. If the ship ever decelerated below light speed, it would seem to you as if you had traveled instantaneously.
There was a young lady named Bright
Who could travel much faster than light
She set off one day
In a relative way
And returned on the previous night.
The article is about leaving the solar system, the sun you refer to is IN our solar system.
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