Yo,
I think throwing away telescopes is a really bad idea. They're very
expensive to build, and I don't think a later one will be much
cheaper. So why not, I thought to myself the other day, send Hubble to
L1, where it will be free to study the cosmos without fear of falling
out of the sky? If it can't be serviced in 2006, at least it will be
in cold storage until we can service it at a future L1 station. So I
checked it out.

It's a heavy telescope to send up that high: Hubble weighs 11,860kg.
L1 takes about an additional 3200m/sec of delta-v from Hubble's
current orbit. Hubble already weighs 11,860 kg by itself. Throw in
engines & tankage (4500 kg for 2 dry centaur derivatives, 460 Isp ea.)
You're already at 16,360 kg minus fuel.
Mo = 16,360kg * e^(3200m/sec /[460sec * 9.8 m/sec^2]) = 33,000 kg.

That's a total mass of 33,000 kg for an L-1 capable Hubble, or an
ADDITIONAL 21,000 kg to LEO to boost Hubble to L1. That's a two Atlas
V 500 or one Delta IV Heavy mission, at about $200 mil for launch
services either way. Anyway this seems like a better idea to me than
providing $100 mil in launch services just to safely deorbit the
Hubble mirror, although there are probably some issues with moving
Hubble by modified Centaur--I believe quite a bit of shaking would be
involved...

Tom Merkle