[time-nuts] Pendulums & Atomic Clocks & Gravity

[Magnus Danielson]

From: "Poul-Henning Kamp" <phk at phk.freebsd.dk>
Subject: Re: [time-nuts] Pendulums & Atomic Clocks & Gravity
Date: Sat, 26 May 2007 22:22:54 +0000
Message-ID: <97235.1180218174 at critter.freebsd.dk>

> In message <71128454-92C4-4AB9-8170-94A29554FD15 at gmail.com>, Neville Michie wri
> tes:
> 
> >These points are good for satelites as the orbit never decays.
> 
> BZZZZT!  Wrong!
> 
> But you came close :-)
> 
> Station keeping in these orbits is much more important than in regular
> freefall orbits, because the domain of stability is not very large.
> 
> For a good story about this, read about the (truly amazing!) recovery
> of the SOHO solar observatory, which is located in such a point.

This was also important for the WMAP mission.

http://map.gsfc.nasa.gov/m_mm/ob_techorbit1.html

They put it in the L2 position.

http://map.gsfc.nasa.gov/m_mm/ob_techorbit.html

WMAP is the follow-up on the COBE project. See recent Nobel price.

Cheers,
Magnus