MSNBC - How a 'safe haven' could help save Hubble

In article ,
Tom Kent wrote:
I don't know of a lot of science missions that are cancelled.

That says more about your limited knowledge than about the state of NASA
science missions, I'm afraid. The canceled ones don't generally issue
salvos of press releases and get major media coverage.

Hubble made it...

Only after quite a struggle, though -- Hubble was originally supposed to
be a mid-1970s project, and it ended up launching at the end of the 1980s.
Moreover, that was a "flagship" project -- NASA could and did sacrifice
other missions to protect Hubble's funding.

...We have all sorts of satellites
and telescopes orbiting the earth, most of which never had to seriously
fight for funding...

You clearly have never participated in trying to get such a mission funded.
*All* of them have to seriously fight for funding.

As a case in point, Hubble originally had an X-ray counterpart, AXAF. It
was repeatedly delayed by funding shortages -- it was supposed to be a
1980s project. A design shakeup in 1992 split it into two spacecraft.
One of them became Chandra, finally launched in 1999... but the other is
dead and forgotten.

...Why is NASA in the telescope
building buisness? Or the monitoring of greenhouse gases buisness for
that matter?
It seems that its becoming more and more that just because the platform
is based in space, it is NASA's juristiction.

This isn't something that's "becoming" -- it's always been this way.
Now mind you, it probably shouldn't be, but it is.

Telescopes are a bit of a different monster. They're still about space
exploration, just from a distance.

Uh, no, they're about astronomy, which only rarely has much to to with
space exploration, despite some superficial similarity.

My view is NASA should step away from its emphasis on science. NASA
should be developing technology to move out into our universe.

There's a lot to be said for that. Trouble is, when NASA proposes to
spend money developing such technology, the response tends to be "and just
which *science missions* require this technology?"
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

In article ,
Brian Thorn wrote:
ISS already has the human-level dexterity... the Hubble robot would
use Canada's robot designed for ISS.

The Hubble robot *may* use Dextre -- my impression is that that hasn't
been decided yet. By the way, despite occasional propaganda, that
hardware is nowhere near achieving human-level dexterity.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

Tom Kent wrote in
. 30.42:

The Russian and European docking systems require all sorts of crazy
hardware like radar dishes and optical sights.

I take it, then, that you've never heard of lidar-based systems, which
require only passive retroreflectors on the target?

lid (John Savard) wrote in
:

Why not just something *real* simple, like a robot mission to boost
Hubble into a way higher orbit... and then, after the successor to the
Shuttle is built, which is not falling apart from advanced age, _then_
go fix the Hubble?

Because HST will most likely be dead by then. When its batteries die, it
loses electrical power, and hence all thermal control over its instruments
and other avionics. Those will quickly succumb to damage due to temperature
extremes. It's not worth saving HST just for the shell - it would be easier
to build a replacement, especially since many of the parts are already
available on the ground.

Henry Spencer wrote:

snip

Unfortunately, there is *nothing* in the pipeline that is a direct and
complete replacement for Hubble. In particular, JWST -- assuming it
actually flies -- completely lacks Hubble's visible and UV capabilities,
and despite what the IR astronomers say, those remain important and
heavily used.

But aren't ground-based telescopes with adaptive optics &c. getting
better than Hubble for visible wavelengths? AFAICT it's IR
instruments that benefit the most from being placed outside the atmosphere.

--
Odysseus

Odysseus wrote:

But aren't ground-based telescopes with adaptive optics &c. getting
better than Hubble for visible wavelengths? AFAICT it's IR
instruments that benefit the most from being placed outside the atmosphere.

HST has other big advantages. It can see in the UV at wavelengths that
don't reach the ground, and its sees a much darker background than
terrestrial scopes (which must put up with airglow), which does
wonderful things to the SNR.

Paul

In article ,
Odysseus wrote:
Unfortunately, there is *nothing* in the pipeline that is a direct and
complete replacement for Hubble...

But aren't ground-based telescopes with adaptive optics &c. getting
better than Hubble for visible wavelengths?

Actually, no. They are approaching its capabilities in *some* respects,
but not in others. For example, Hubble is still inherently superior for
observing extremely dim objects, because it has a much darker sky
background -- even at night at very dark sites, there is light from the
atmosphere.

AFAICT it's IR
instruments that benefit the most from being placed outside the atmosphere.

*And* ultraviolet instruments. Hubble does a lot of UV work.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

What are the implications to ISS if Dextre is hijacked for the HST
repair mission?

Bill the Cat wrote in news:Xns95B9C8EC7D2F8billthecat@
216.196.97.130:

Tom Kent wrote in
. 30.42:

The Russian and European docking systems require all sorts of crazy
hardware like radar dishes and optical sights.

I take it, then, that you've never heard of lidar-based systems, which
require only passive retroreflectors on the target?




Yeah, I have. I believe that's what the European's are working with....a
lidar isn't a cheap light thing....not on the order of a digital camera
anyway. (Not that what they go to the hubble with will be, but it could
be.....that's kinda where dart was heading)

(Henry Spencer) wrote in :

In article ,
Brian Thorn wrote:
ISS already has the human-level dexterity... the Hubble robot would
use Canada's robot designed for ISS.

The Hubble robot *may* use Dextre -- my impression is that that hasn't
been decided yet. By the way, despite occasional propaganda, that
hardware is nowhere near achieving human-level dexterity.

Its not human level, like you or I....more like the dexterity of a human in
a space suit. Maybe not exactaly, but getting close.

Tom