Send Hubble to L1! what would it take...

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

"Tom Merkle" wrote:
I believe quite a bit of shaking would be involved...

Thus rendering HST at L1 a useless pile of junk. "Shaking" of any kind is
not acceptable in HST's current deployed condition. Activities by EVA
astronauts during repair flights were *strictly* limited as to contact with
HST.

Roger
--
Roger Balettie
former Flight Dynamics Officer
Space Shuttle Mission Control
http://www.balettie.com/

"Roger Balettie" wrote in message ...
"Tom Merkle" wrote:
I believe quite a bit of shaking would be involved...

Thus rendering HST at L1 a useless pile of junk. "Shaking" of any kind is
not acceptable in HST's current deployed condition. Activities by EVA
astronauts during repair flights were *strictly* limited as to contact with
HST.

Roger

Yes, but Hubble made it through a shuttle flight to orbit ok. Is there
any way to remotely 'undeploy' the vulnerable components, like solar
panels? What components are particularly vulnerable?

The alternate plan if astronaut presence is required to stow Hubble
for boost is to remotely attach a small ion thruster or tether system
that can GENTLY move it to a higher orbit as a temporary measure, (to
revent unplanned reentry) until such time as astronauts can visit (in
a CEV or whatever) to get it ready for transfer to L1.

Would Van Allen radiation do anything to the optics or CCDs?

Tom Merkle

Hubble isn't in the same orbital plane as the moon right now, is it?

Though I guess doing a plane change at lunar orbit wouldn't take much
more delta-v.

Would too much of the LH2 for a Centaur boil off, before you got to
lunar orbital altitude? Time of flight in the transfer orbit would be
about five days?

Tom Merkle wrote:

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

"Rod Montgomery" wrote in message
hlink.net...
Hubble isn't in the same orbital plane as the moon right now, is it?

Though I guess doing a plane change at lunar orbit wouldn't take much
more delta-v.

Would too much of the LH2 for a Centaur boil off, before you got to
lunar orbital altitude? Time of flight in the transfer orbit would be
about five days?


I think the rough rule of thumb is that in LEO one percent of the LH2 will
boil off each month, with a well-insulated tank.

Regards
Jonathan Wilson

In article ,
Jonathan Wilson wrote:
Would too much of the LH2 for a Centaur boil off, before you got to
lunar orbital altitude? Time of flight in the transfer orbit would be
about five days?

I think the rough rule of thumb is that in LEO one percent of the LH2 will
boil off each month, with a well-insulated tank.

Must be a very well-insulated tank. Apollo S-IVB boiloff rates were quite
substantially higher than that, despite insulation -- Apollo loiter time
in parking orbit was only three or four orbits total, after which TLI
capability was no longer available due to LH2 boiloff.
--
MOST launched 30 June; science observations running | Henry Spencer
since Oct; first surprises seen; papers pending. |

Rod Montgomery wrote in message thlink.net...
Hubble isn't in the same orbital plane as the moon right now, is it?

Though I guess doing a plane change at lunar orbit wouldn't take much
more delta-v.

Would too much of the LH2 for a Centaur boil off, before you got to
lunar orbital altitude? Time of flight in the transfer orbit would be
about five days?

Tom Merkle wrote:

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



How about a market guarantee of $250 million to do whatever
is necessary and appropriate: 1) provide good, manned access
in Hubble's present orbit; 2) "crate" it for shipping and
then move it; 3) ????.

Our Space Van 2008 could do the job--as well as many other
jobs--and could be developed, IMO, within a $200 million
budget with a free hand and the right kind of project-
oriented management. A $250 million market guarantee might
be just the ticket to get investor interest.

Other would-be space transportation companies could come
up with other missions--and, perhaps, be a backup for
the Hubble Rescue Mission (HRM). PanAero would like
first dibs on HRM. :)

Best regards,
Len (Cormier)
PanAero, Inc.
(change x to len)
http://www.tour2space.com