warpus
In pork I trust
Hey Hobbs! Can you explain how something can stay in the same orbit but slow down? You are my only hope
The thread for space cadets!
- Thread starter hobbsyoyo
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It cannot. (Except if the orbit is around something rapidly losing mass).
But once you talk about starting or landing maneuvers, you need to stop talking about orbits.
warpus
In pork I trust
Sounds like there was some miscommunication in the previous posts. I've been saying all along that it does't seem possible to do such a thing
Berzerker
Deity
There's a scene in the movie 2010 (the sequel to 2001) where the Russian ship Leoniv uses Jupiter's atmosphere to slow down by inflating large bags surrounding the ship as it slips in and out of the upper atmosphere.
warpus
In pork I trust
That's a specific type of aerobreaking, right? A fun way to slow down if you know what you're doing. Each time you dip into the atmosphere you slow down and your orbit (on the other side of the planet) gets smaller (from my understanding and experience)
If I understood correctly, you asked if it's possible to travel by the same trajectory as usual circular orbit, but at slower speed. It is possible, but your engines must be turned on at all time.
You can 'travel' at zero speed, if you want. Just get to the altitude you need and maintain it by running engines.
Reminds me about "The Way to Amalthea" novella. Cargo spaceship was delivering goods to research station on Amalthea, got hit by meteorites near Jupiter and started falling down into it. One of the authors was astronomer.
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warpus
In pork I trust
Uppi is saying that is not possible, in one of the posts above. I am still confused about all this and what is actually true..
He meant inertial motion (engines off), which is indeed impossible in this case.
Berzerker
Deity
yes, that was the term they used in the movie... Looked like a meteor skipping in and off the atmosphere in a big fireball
I know the sequel was panned a bit but I liked 2010, answered the big questions left from 2001
Ya, the engines must be pointed at the center of the Earth if Earth is the object being orbited.
Other options include Earth losing mass as Uppi stated, or someone changing the gravitational constant of the universe.
warpus
In pork I trust
If you did that in KSP you would def. not stay on the same orbit or even another orbit with the same diameter. It also differs from the explanation on the previous page that says that you also have to be firing retrograde at the same time. This is all just adding to the confusion for me.
@Berzerker The 4 Space Odyssey books are good, although I didn't really like 3001 all that much. The 3 Time Odyssey novels pick up the story and are good as well, but they're.. different
@Berzerker The 4 Space Odyssey books are good, although I didn't really like 3001 all that much. The 3 Time Odyssey novels pick up the story and are good as well, but they're.. different
You'll need retrograde to slow down if you are already on the orbit.
If you want to take off and keep same altitude maintaining zero speed (as in my example), obviously aim at the center of the Earth.
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Berzerker
Deity
Huh, I didn't know there were 4 books to the space odyssey
warpus
In pork I trust
There's:
2001: A Space Odyssey
2010: Odyssey Two
2061: Odyssey Three
3001: The Final Odyssey
Time's Eye
Sunstorm
Firstborn
The last 3 books on the list are an "orthoquel", according to Clarke. It's an orthogonal sequel, which is just his way of saying that it's set in the same universe and.. it's clever cause time and space..
I don't remember much about 3001 tbh. I do remember thinking that it probably didn't need to be written, after I read it.. The Time books are good though, I enjoyed them
Berzerker
Deity
I dont read books any more and I'll be dead before the rest become moviesI suppose I could look for something on utube, might be some short versions there
do we at any point get invaded by Europans?
warpus
In pork I trust
The Time ones are actually interesting in that you have people from various historical eras all in the same place. I don't really want to give anything away, but there's some interesting scenarios involving generals and leaders from various eras
I doubt they'll be ever made into movies. They don't really follow the story from the Space Odyssey books. They sort of do, but not in a linear fashion, and it's all new characters IIRC
As for 3001, I think it was written around 2000. I think he just wanted to cash in on the whole 2k/3k thing *shrug*
I doubt they'll be ever made into movies. They don't really follow the story from the Space Odyssey books. They sort of do, but not in a linear fashion, and it's all new characters IIRC
As for 3001, I think it was written around 2000. I think he just wanted to cash in on the whole 2k/3k thing *shrug*
As I said: stop thinking about orbits when discussing this. As long as the engines are doing anything, you are not in an orbit. So any considerations involving orbits are not applicable.
In space you can fly an trajectory you want, no matter the orbits, as long as you have enough fuel. Since fuel is usually quite important in space, spacecraft usually try to make use of orbits as much as possible. But that does in no way mean they have to follow orbits.
warpus
In pork I trust
That's why I first objected. When your engines fire, your orbit changes, no matter which direction you're burning in. So when I saw "you can stay in the same orbit but slow down", that did not sound right to me.
But aren't you, btw? The ISS has engines firing all the time and it's in orbit. I suspect this is an academic distinction
Anyhow, I think I know what's going on here. It's not that you can stay in the same orbit while firing your engines.. it's that you can stay on the same flight path while slowing down. Right? That's what's being said in this thread? I am just trying to understand this thing.
Right.
Going slower along the path circling the Earth while firing engines at Earth to compensate can make the same circle around Earth that a normal orbit does.
warpus
In pork I trust
Well, thanks for indulging me while I came to terms with all this and have now finally wrapped my head around it I think
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