My Hubble Thoughts

In article ,
Rand Simberg wrote:
http://www.techcentralstation.com/020905E.html

It bends over backward to respectfully disagree with a shabby, political
decision. O'Keefe cancelled the Hubble service mission because the
space station needs its shuttle flight. That's the real bottom line.
NASA didn't at all "overestimate its love of the ISS". No, O'Keefe
nailed NASA's devotion to the space station exactly. A good science
project is indeed being cut for an expensive manned fiasco.

--
/\ Greg Kuperberg (UC Davis)
/ \ Home page: http://www.math.ucdavis.edu/~greg/
\ / Visit the Math ArXiv Front at http://front.math.ucdavis.edu/
\/ * All the math that's fit to e-print *

A large telescope suspended from a balloon above
the troposphere would make pictures as good as the
Hubble pictures, but it would cost less than Hubble.

A simple tilt mirror can stabilize the telescope
image up to 15 arcsec (7.27x10^-5 radians).
Source: http://sd-www.jhuapl.edu/FlareGenesi..._4014_p214.pdf
This is sufficient stability to get the full,
diffraction limited resolution from a telescope
having the aperture diameter of about one
centimeter. A much more sophisticated system made
of the tilt mirror and a separate system stabilizing
the housing can improve the stability by at least
three orders of magnitude, which is sufficient
for a telescope having the aperture diameter of
ten meters.

The outer space is the best location for very
large telescopes (diameter bigger than 10 meters)
because gravity distorts very large terrestrial
telescopes and because balloons cannot easily
lift very heavy loads.

At TechCentralStation today:

http://www.techcentralstation.com/020905E.html

In article ,
Rand Simberg wrote:
On Wed, 9 Feb 2005 17:24:57 +0000 (UTC), in a place far, far away,
(Greg Kuperberg) made the phosphor on my monitor
glow in such a way as to indicate that:
....
A good science project is indeed being cut for an expensive manned fiasco.
But not for the VSE, which is what critics were unjustifiably
complaining about.

Yes and no. The Hubble service mission was cut because of the space
station, so the question is whether or not the space station is part of
the vision for exploration. Your comment presupposes that it isn't.
But William Gerstenmaier, the space station program manager, sees it
differently:

We don't see hardly any changes to our program based on the new
initiative - we're pretty well aligned with it to begin with.

http://www.abc.net.au/news/newsitems/s1030986.htm

[The] Space Station fits very well into the Vision for Space
Exploration.

http://www1.jsc.nasa.gov/jscfeatures/articles/000000238.html

--
/\ Greg Kuperberg (UC Davis)
/ \ Home page: http://www.math.ucdavis.edu/~greg/
\ / Visit the Math ArXiv Front at http://front.math.ucdavis.edu/
\/ * All the math that's fit to e-print *

Andrew Nowicki wrote:
A large telescope suspended from a balloon above
the troposphere would make pictures as good as the
Hubble pictures, but it would cost less than Hubble.

Off on a tangent, but if you hung a couple of tons worth of telescope
up in stratosphere on a balloon ( which are known to burst, eventually
) would it have to carry some sort of range safety device ?

-kert

Andrew Nowicki wrote:
A large telescope suspended from a balloon above
the troposphere would make pictures as good as the
Hubble pictures, but it would cost less than Hubble.

kert wrote:
Off on a tangent, but if you hung a couple of tons worth of telescope
up in stratosphere on a balloon ( which are known to burst, eventually
) would it have to carry some sort of range safety device ?

The old balloon does not explode, but rather it
leaks slowly, so the kinetic energy of the descending
telescope is small. The range safety device is
not needed, but inflated bags around the telescope
are needed to prevent damage and sinking of the
expensive telescope. The polar regions are the
best places for the telescope.

On Wed, 9 Feb 2005 17:24:57 +0000 (UTC), in a place far, far away,
(Greg Kuperberg) made the phosphor on my monitor
glow in such a way as to indicate that:

In article ,
Rand Simberg wrote:
http://www.techcentralstation.com/020905E.html

It bends over backward to respectfully disagree with a shabby, political
decision. O'Keefe cancelled the Hubble service mission because the
space station needs its shuttle flight. That's the real bottom line.
NASA didn't at all "overestimate its love of the ISS". No, O'Keefe
nailed NASA's devotion to the space station exactly. A good science
project is indeed being cut for an expensive manned fiasco.

But not for the VSE, which is what critics were unjustifiably
complaining about.

In article ,
Rand Simberg wrote:
On Wed, 9 Feb 2005 19:44:17 +0000 (UTC), in a place far, far away,
(Greg Kuperberg) made the phosphor on my monitor
glow in such a way as to indicate that:
A good science project is indeed being cut for an expensive manned fiasco.
But not for the VSE, which is what critics were unjustifiably
complaining about.
Yes and no. The Hubble service mission was cut because of the space
station, so the question is whether or not the space station is part of
the vision for exploration.
That's not a question, or if it is, the answer is largely no.

I know very well that you think that the space station is not part of
the vision for space exploration, or "largely" not part of it. But many
other people, including both fans and critics of Bush and O'Keefe, think
that it is a large part of the VSE. Your description of "critics"
in your TCS article isn't accurate.

William Gerstenmaier, the space station program manager:
....
We don't see hardly any changes to our program based on the new
initiative - we're pretty well aligned with it to begin with.
http://www.abc.net.au/news/newsitems/s1030986.htm

[The] Space Station fits very well into the Vision for Space
Exploration.
http://www1.jsc.nasa.gov/jscfeatures/articles/000000238.html
What in the hell would you have expected him to say? That it's
useless, and doesn't fit into it?

If the VSE really were a move away from the space station, I might have
expected Gerstenmaier to sound opposed, defensive, braced for change,
resigned, or at least wistful. But he doesn't sound like any of that;
he sounds smug. Even though I don't really trust Gerstenmaier, his
smug attitude has a real ring of truth to it, more so than what you have
to say.

--
/\ Greg Kuperberg (UC Davis)
/ \ Home page: http://www.math.ucdavis.edu/~greg/
\ / Visit the Math ArXiv Front at http://front.math.ucdavis.edu/
\/ * All the math that's fit to e-print *

kert wrote:
Off on a tangent, but if you hung a couple of tons worth of telescope
up in stratosphere on a balloon ( which are known to burst, eventually
) would it have to carry some sort of range safety device ?

A toy rubber balloon bursts when you prick it, but
a well designed stratospheric balloon does not
burst because its envelope is made of DuPont
Teijin Teonex Q72 film (polyethylene naphthalate),
and because it has a feature that prevents the
enlargement of small holes: either reinforced
seams (like sails), or a net holding the envelope.

Rand Simberg wrote:
It was pretty clear that the only reason that we're bothering to keep
Shuttle going and finish station is to fulfill international
obligations, not because it plays any fundamental role in VSE. It's
clear that Shuttle/ISS are a budgetary and resource diversion from
VSE, and the focus of the new policy was to get out of both
businesses
as soon as politically possible in order to free up funds for the
real
goals.
Just a thought, but if it was politically and legally possible, i think
every partner involved would be quietly happier if instead of finishing
ISS US would find different methods of fulfilling its obligations.
4-5 Billion a year currently spent on STS could go a long way in making
the respective *SA-s happy.
IOW, declare victory and go home with ISS. Which would bring up the
issue of deorbiting the white proboscideus...

-kert