– Okay, so the solar system is hurtling through space at around 200km/s and by extension so are the planets. I get that we can launch a rocket and land it on another planet, but does this mean that the rocket would also be travelling at approx 200km/s as well?

Question

And additionally, would it ever be possible to launch something into deep space and get entirely left in the dust by the solar system whizzing by? Completely untethered from its gravity?

In: 9

Answer 1

Things don’t move unless something makes them move.

But things don’t STOP unless something makes them stop. That’s also true.

Because everything is going 200km/s, and there’s nothing causing it to stop because intergalactic space is almost entirely a vaccuum and there’s nothing out there for it to rub against or impact or push at it, everything will continue going 200km/s until that changes.

The reason we don’t SEEM to be going 200km/s is because everything around us is. If you’re on a passenger train going 50km/hr and you drop your teaspoon, it’s not going 50km/h relative to YOU and in YOUR sight. You just see it drop straight down, bounce, and stop. But it absolutely IS going that speed to someone outside the train that’s watching you go by and looking in your window to see you drop it.

We’re in the galaxy which is our “train” and the rocket is our “teaspoon”. To someone outside the galaxy, it goes by at 200km/s. To everyone inside the galaxy, it’s not. So when it’s on the launch pad or landing site, 200km/s is its speed to galaxy outsiders, but 0 to us. And when it’s in flight it’s going 200km/s to the outsiders, plus or minus a little bit depending on its direction.