Artemis II

Why do satellites stay in orbit then instead of crashing back down to earth?
Because they're travelling fast enough not to. Their trajectory follows the arc/curve of the Earth (sorry to all the flat earth weirdos across the globe).
 
Ask not why they’ve not gone back for 54years why they went in the first place!? To be first! Russia was first into space first with an animal in space a dog!

Now why they coming back again now because China said they are going to put a man on the moon by 2036 but the dark side where there is a possibility of ice, apparently there is massive craters on that side and because the sun don’t hit that part of the moon for long those massive craters have more chance of ice because less chance of melting!

The dark side of the moons is a myth. There is a far side of the moon which we don't see because the moon is tidally locked to the Earth so one side is always facing us.

That side of the moon gets just as much sunlight.

You're right that there are seemingly pockets of water ice though in craters or bases of mountain ranges that shield the ground from the sun.

If mankind ever have bases there then long term there are ideas to use and reuse this water.
 
Why do satellites stay in orbit then instead of crashing back down to earth?

They are travelling too fast. They're falling but falling around the arc of the Earth.

Many are in the thermosphere or Low Earth Orbit and still get dragged by atmospheric particles so they have thrusters to keep their speed.

If they slowed then they'd enter the atmosphere and burn up.
 
They are travelling too fast. They're falling but falling around the arc of the Earth.

Many are in the thermosphere or Low Earth Orbit and still get dragged by atmospheric particles so they have thrusters to keep their speed.

If they slowed then they'd enter the atmosphere and burn up.
That's bullshit
Mo Salah travels fast and he's always falling to the earth
 
I've had a few beers.
But...
And I'm expecting loads of people to have a go.
But I'm going to say it anyway.
If man went to the moon 50 odd years ago.
Why have they not been since.
Next to Buxton is a village called dove holes.
It was voted the ugliest village in Britain.
If Ithey landed in dove for the first time I can understand them saying fuck that were not going there again

There was/is still lots of science and engineering NASA wanted to do but cost was prohibitive.

Might soon be prohibitive again as Trumps government wants to cut NASA funding by nearly 30%.
 
The thing that interested me (well it all interests me really) is that you can't do a single burn that puts you into a lunar orbit. Not according to ChatGPT anyway.

You do the translunar injection burn, but with a free return built in, and that's what has happened. But if you want to orbit the moon you have to fire the engine again whilst going around it to slow you enough to stay captured by its gravity.

I'd have thought there would be a sweet spot of hitting just the right speed as you reach the moon to then remain in orbit. I hadn't thought about this with regard to Apollo, but it is surprising that it can't be done, it would mean one less burn to get into lunar orbit.
 
They'll come back and say how many stars they could see! That was a thing wasn't it? When those guys that supposedly landed on the moon said they didn't see any stars? Out of the lunar module, they go oh the sun wasn't pointing the right way.. Meanwhile stars are Suns!
Oh here come the loons. Ffs.
 
Last edited:
The thing that interested me (well it all interests me really) is that you can't do a single burn that puts you into a lunar orbit. Not according to ChatGPT anyway.

You do the translunar injection burn, but with a free return built in, and that's what has happened. But if you want to orbit the moon you have to fire the engine again whilst going around it to slow you enough to stay captured by its gravity.

I'd have thought there would be a sweet spot of hitting just the right speed as you reach the moon to then remain in orbit. I hadn't thought about this with regard to Apollo, but it is surprising that it can't be done, it would mean one less burn to get into lunar orbit.

This is correct, and I think one way of thinking about it is that you have to remember everything is moving relative to everything else. The moon isn't a static target, it is also orbiting the Earth - and the velocity you travel at is a vector, it is not just a speed but also a direction. You can do a burn that puts you moving further out and this increases your velocity relative to the Earth, and puts you "on target" to the moon - and you can do this so your arrival "speed" relative to Earth is very low. But then because the moon is also orbiting sideways it is going to blow past you, and that means your velocity vector relative to the moon is always going to be coming in "too hot", so you need another burn to enter its orbit.
 
The thing that interested me (well it all interests me really) is that you can't do a single burn that puts you into a lunar orbit. Not according to ChatGPT anyway.

You do the translunar injection burn, but with a free return built in, and that's what has happened. But if you want to orbit the moon you have to fire the engine again whilst going around it to slow you enough to stay captured by its gravity.

I'd have thought there would be a sweet spot of hitting just the right speed as you reach the moon to then remain in orbit. I hadn't thought about this with regard to Apollo, but it is surprising that it can't be done, it would mean one less burn to get into lunar orbit.

I think Apollo 11 was the last free return trajectory mission. It shows it can be done but it's very risky. Apollo 11 missed it's intended landing spot and it could have gone very badly.

So they use burns to slow and navigate their landing but then this requires an extra burn after lift off again to realign their trajectory with the Earth.

I don't know if during the 50 years they have come up with a better plan and using less fuel.
 

Don't have an account? Register now and see fewer ads!

SIGN UP
Back
Top