Universe Sandbox

Universe Sandbox Legacy => Universe Sandbox 2008 | Help => Topic started by: georgelpreput on February 26, 2009, 09:48:49 AM

Title: Earth and Moon L-Points Unstable
Post by: georgelpreput on February 26, 2009, 09:48:49 AM: Hi,

I am using version 1.0.370.0, updated to 1.0.400.0, and when loading the Lagragian Points - Earth & Moon system, it gets unstable virtually in the first minute of running. I attached a screenshot.

Edit: I've just downloaded 1.0.424.0, and it's the same.
Title: Re: Earth and Moon L-Points Unstable
Post by: FGFG on February 26, 2009, 12:38:59 PM: L1, L2 and L3 are very unstable points. It's as if you try to get a reversed cone balanced: it's possible, but it is very improbable ;)

L4 and L5, instead, are more stable (an object of trascurable mass could remain in orbit near them indefinitely)
Title: Re: Earth and Moon L-Points Unstable
Post by: atomic7732 on February 26, 2009, 03:23:14 PM: Just use the Lagrange Points button and see how stable they REALLY are.
Title: Re: Earth and Moon L-Points Unstable
Post by: georgelpreput on February 27, 2009, 02:56:21 AM: I think the problem is L1 and L2 being around the moon, instead of around the Earth.
Title: Re: Earth and Moon L-Points Unstable
Post by: Dan Dixon on March 02, 2009, 06:56:20 PM: Yes... The L1 & L2 points seem to be even more unstable than they should be. I've thought the same thing.

It's possible that my math is wrong (which is why you should never use Universe Sandbox to launch rockets to other planets). Specifically I think that the calculation for the velocities of objects at those points may be slightly off, but I'm not sure.

(And the Lagrange point math hasn't been updated since 1.0.370.0.)
Title: Re: Earth and Moon L-Points Unstable
Post by: atomic7732 on March 03, 2009, 07:20:23 AM: Quote from: Dan Dixon on March 02, 2009, 06:56:20 PM
Yes... The L1 & L2 points seem to be even more unstable than they should be. I've thought the same thing.

It's possible that my math is wrong (which is why you should never use Universe Sandbox to launch rockets to other planets). Specifically I think that the calculation for the velocities of objects at those points may be slightly off, but I'm not sure.

(And the Lagrange point math hasn't been updated since 1.0.370.0.)
I want to launch rockets to oter planets!
Title: Re: Earth and Moon L-Points Unstable
Post by: Chaotic Cow on March 03, 2009, 03:34:08 PM: Quote from: NeutronStar on March 03, 2009, 07:20:23 AM
Quote from: Dan Dixon on March 02, 2009, 06:56:20 PM
Yes... The L1 & L2 points seem to be even more unstable than they should be. I've thought the same thing.

It's possible that my math is wrong (which is why you should never use Universe Sandbox to launch rockets to other planets). Specifically I think that the calculation for the velocities of objects at those points may be slightly off, but I'm not sure.

(And the Lagrange point math hasn't been updated since 1.0.370.0.)
I want to launch rockets to oter planets!

Exactly my thought when I read this.
Title: Re: Earth and Moon L-Points Unstable
Post by: Andreas on March 30, 2009, 04:08:05 AM: Quote from: NeutronStar on March 03, 2009, 07:20:23 AM
Quote from: Dan Dixon on March 02, 2009, 06:56:20 PM
Yes... The L1 & L2 points seem to be even more unstable than they should be. I've thought the same thing.

It's possible that my math is wrong (which is why you should never use Universe Sandbox to launch rockets to other planets). Specifically I think that the calculation for the velocities of objects at those points may be slightly off, but I'm not sure.

(And the Lagrange point math hasn't been updated since 1.0.370.0.)
I want to launch rockets to oter planets!

Make sure, that you sit in it. Thanks
Title: Re: Earth and Moon L-Points Unstable
Post by: Dan Dixon on March 30, 2009, 03:00:23 PM: Quote from: Andreas on March 30, 2009, 04:08:05 AM
Make sure, that you sit in it. Thanks

What do you mean? The rocketship?
Title: Re: Earth and Moon L-Points Unstable
Post by: Andreas on March 31, 2009, 12:50:08 AM: NeutronStar said he want launch rockets to other planets.
I just said, that he should sit in the rocket ;)
Title: Re: Earth and Moon L-Points Unstable
Post by: monmarfori on April 06, 2009, 05:27:26 PM: Because a future version may fix that
Title: Re: Earth and Moon L-Points Unstable
Post by: Naru523 on November 01, 2009, 10:01:27 PM: Quote from: deoxy99 on November 01, 2009, 06:50:02 PM
Unstable? Not really. Nothing in the photo is...

L2 got off of Moon's hillsphere and L1 is orbiting the Moon. and Maybe L3 is not on the opposite orbit of the Moon.
Title: Re: Earth and Moon L-Points Unstable
Post by: Naru523 on November 03, 2009, 08:53:56 PM: I dont think you get it...
Title: Re: Earth and Moon L-Points Unstable
Post by: atomic7732 on November 04, 2009, 09:18:03 PM: Case closed! Stop saying case closed!

No seriously, why do you say that alot?
Title: Re: Earth and Moon L-Points Unstable
Post by: atomic7732 on November 04, 2009, 09:19:34 PM: No one ever came to a decision or argument. So I see no reason.
Title: Re: Earth and Moon L-Points Unstable
Post by: Naru523 on November 04, 2009, 10:08:34 PM: True.
Title: Re: Earth and Moon L-Points Unstable
Post by: Dan Dixon on November 05, 2009, 11:55:32 AM: Like I said originally... It's very likely that the L points are slightly off. They're definitely close, but they may not be perfect.
Title: Re: Earth and Moon L-Points Unstable
Post by: atomic7732 on November 05, 2009, 07:30:31 PM: gosh deoxy...
Title: Re: Earth and Moon L-Points Unstable
Post by: Naru523 on November 05, 2009, 11:01:22 PM: Compare them with the L-Points button...