Gravitational Interactions

[Whatu]

Hi!

I was wondering about a thing...

Can I create a new planet with a low radius and high mass so density is something like say, iridium? I guess this is feasible but i want to hear some opinions first.

And now the question. If I can make such a planetoid, and make it very massive, and put it in a highly eccentric orbit around the sun, and somehow manage to tweak the orbit so it passes near the Earth, (or the moon)...

I guess that if it is massive enough, the Earth (or moon) orbit would be changed?

I want to make an scenario in which, for example, this planetoid passes near the moon at a desired date (tweaking the orbit for this to happen could be very difficult?) and it disturbs the orbit of the moon, and the moon falls to the planet, or gets ejected to a sun orbit...

Is this kind of gravitational effects modelled in orbiter?

I hope I made myself clear, just want to hear any constructive or destructive criticism (preferably constructive)

 

[Zatnikitelman]

One thing I've wondered that goes along with this is what happens if two planets or moons or such collides in Orbiter?
(sorry to hijack your topic a little there, but you might be onto something interesting here )

 

[Whatu]

One thing I've wondered that goes along with this is what happens if two planets or moons or such collides in Orbiter?
(sorry to hijack your topic a little there, but you might be onto something interesting here )

Hmm I guess they will ignore each other, just like vessel-vessel collition?
Or maybe it generates a mega-cataclism in real life

 

[Artlav]

Neither will work.
The planet trajectories are fixed, so even if you turn Mars into galactic black hole, the Earth won't move a bit.

Same for collisions, really - the planets just pass thru each other, only if the vessel is cached in-between there goes something interesting.

Crashing Ceres into the Earth:

Closing in:

It is on the other side, not inside:

Entering the athmosphere:

Desperate attempt to run away:

The imminent impact:

The result of the post-crash bugs:

 

[YL3GDY]

That's quite funny! But it's not so interesting (One more thing to "Orbiter limitations" thread ).
Anyway, I guess that defining planets as vessels with it's mesh would be even worse: you can't then land on it, only fall through.

 

[Whatu]

Haha yes that was fun. Artlav, how did you manage to "crash" Ceres into earth?

Also it seems odd to me that Ceres is visible trough the Earth... why is that? Does it happen with every planet if it is near enough Earth?
And why does it turn blue when in atmosphere? I guess its just bugs because Orbiter is not meant to do this kind of things...

So planets orbits are fixed..

What do you think about implementing non-fixed orbits in Orbiter? Too difficult? Too useless? And what about planet-planet collisions? Not that neither of this is really needed, just wondering about Orbiter's capabilities...

And about the black-hole thing... can I really turn Mars into a black-hole? Giving it a really high mass and no mesh? It wouldnt affect Earth's orbit but.. what would happen to a DeltaGlider for example? Would it feel the inmense gravitation if its landed on Earth?
Would it accelerate to light-speed (or even more) if its close enough?
mm so many questions...

 

[steph]

I doubt a black hole with the mass of Mars would have any influence on Earth, exactly because it still has the mass of Mars. Gravity is just more concentrated around it.
And nothing can reach light speed. In real life. In Orbiter, I guess you could reach an orbit where the speed is equal to that of light, although due to the radius of the black hole, the orbit would have a radius of about a few millimeters. The orbit where you have light speed in Orbiter is where the event horizon would be in real life.

 

[Whatu]

I doubt a black hole with the mass of Mars would have any influence on Earth, exactly because it still has the mass of Mars. Gravity is just more concentrated around it.
And nothing can reach light speed. In real life. In Orbiter, I guess you could reach an orbit where the speed is equal to that of light, although due to the radius of the black hole, the orbit would have a radius of about a few millimeters. The orbit where you have light speed in Orbiter is where the event horizon would be in real life.

I didnt mean a black hole with the mass of mars, but rather a typical black hole with a mass several times that of sun, just the mass is concentrated in a sphere maybe even smaller than mars.

And, gravity more concentrated around it? I guess that in a black hole gravitational potential will decrease with distance by the normal standard, the inverse square of the distance. So in earth, this gravitational potential will be much less than in the event horizon, but maybe still a lot? (so in real life the earth would be automatically sucked in the hole, but in talking in "orbiter physics" where the earth is fixed in its orbit, so the gravitation would only affect the vessel).

Well I guess I will try some CFG editing this afternoon and post any interesting result (if any) tonight.

Keep sending your opinions!

Edit: I just made the mass of mars to be 6.418542e+29 rather than the original 6.418542e+23.

I loaded the scenario "beatiful landing on phobos" where you start near phobos. The gravity vector was so long it reached mars. The glider falls to mars in about 4 seconds, and 6 or so seconds after that im already out of the solar system at an incredible speed. Fun, now im gonna try to go to this new and heavy mars from earth.

 

[Bj]

Neither will work.
The planet trajectories are fixed, so even if you turn Mars into galactic black hole, the Earth won't move a bit.

Same for collisions, really - the planets just pass thru each other, only if the vessel is cached in-between there goes something interesting.

Crashing Ceres into the Earth:
[image]
Closing in:
[image]
It is on the other side, not inside:
[image]
Entering the athmosphere:
[image]
Desperate attempt to run away:
[image]
The imminent impact:
[image]
The result of the post-crash bugs:
[image]

Artlav, your links are bad, I cannot view the pictures

 

[Eagle]

Maybe somebody should come up with a gravity playground solar system where gravity is exaggerated and distances are small so Lagrange points are obvious and slings are hilarious.

Maybe a few close passes where objects on the surface of one moon are transfered to another.

I guess moving all the planets to about Mercury's orbit should be sufficient.

 

[TSPenguin]

Artlav, your links are bad, I cannot view the pictures

His links are fine. Pictures are working for me and several others I know from different ISPs. Check if you can reach his site, he hosts them on his server.
The problem has to be on your end somewhere.

 

[fresh squid]

same problem here BJ maybe a firefox issue?. What browser are you using?

 

[Whatu]

same problem here BJ maybe a firefox issue?. What browser are you using?

I'm using Firefox, not having any problem to view the pics.

 

[Artlav]

Artlav, your links are bad, I cannot view the pictures

His links are fine. Pictures are working for me and several others I know from different ISPs. Check if you can reach his site, he hosts them on his server.
The problem has to be on your end somewhere.

same problem here BJ maybe a firefox issue?. What browser are you using?

I'm using Firefox, not having any problem to view the pics.

The server is up, so the problem is probably on your end.

One way to check it - try viewing:
1. http://81.176.226.166
2. http://l2.in-solve.ru
3. http://orbides.1gb.ru

If first gives following error text and others gives nothing (like "The page you requested could not be loaded"), then it's DNS problem.
If all gives nothing, then it's connection problem.
If first 2 gives following error text and third gives nothing, then it's unknown problem.
If first 2 gives following error text and third gives normal site, then it's your browser set-up problem.

Normal error text:

404 File (site) not found
This page was generated by 1Gb.ru hosting server l2.in-solve.ru (Apache).
If you have any questions, please contact [email protected]

 

[Whatu]

Well about the "high density" mars experiment...

I did a standard mars injection, everything ok.
Obviously, with such a mass, mars Soi was big enough to even touch a little earth's orbit.

First "weird" thing I noticed was in the Map screen of IMFD... (I have the Asteroid Pack installed).

Mercury's orbit (and 2 asteroid's orbit) where centered in mars!! The orbits had not changed (everything was moving in the usual way), but the imfd map represented the mercury orbit not around the sun, but around mars... weird thing. (it was changing constantly with time, of course).

Besides that, Mars influence began to be felt waaaay long before reaching mars. Just after leaving earth's Soi, the "G" indicator in OrbitMFD showed almost 0.20 for mars. I first aimed for a PeD of 17.xxM approximately. When I was there there still wasnt any gravity vector towards mars. I did retrogade burn to set the PeD to about 1M. (by the way this costed me a couple of full tanks of propellant) As I got nearer the gravity vector grew rapidly, showing 50 MegaNewtons at that distance. Further retrogade burning to lower PeD even more was so fuel consuming that I quitted.

Conclusions:
-Manouvering near such a massive object requires massive amounts of fuel.
-If I was an astronaut I wouldnt like to see myself in such a situation, and even less near a real black-hole! (mars had about the Sun's mass)

-It would be nice if, in future orbiter versions, planet's orbit where really affected by other masses (for example, to set a scenario where a massive asteroid disturbates the moons orbit).

Useless? maybe, but would be nice to see nonetheless.