![]() |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
![]()
In article ,
OrionCA wrote: On Sat, 22 Jan 2005 09:27:57 -0600, richard schumacher wrote: http://www.space.com/news/hubble_budget_050121.html "The White House has eliminated funding for a mission to service the Hubble Space Telescope from its 2006 budget request and directed NASA to focus solely on de-orbiting the popular spacecraft at the end of its life, according to government and industry sources." No surprise here. Bush gets all his science from the christian bible. Time to write our congresspeople to direct NASA to save Hubble. All future Shuttle missions must include the capability to reach the ISS in case of a major emergency that precludes re-entry. Hubble is in an orbit that the three remaining Shuttles can't attain and still reach the ISS. Ergo, no Hubble resupply missions are planned. That is an arbitrary choice. A Shuttle mission to Hubble is not significantly more dangerous than to ISS; true, there's no "safe haven" at Hubble (and as we see repeatedly ISS is not all that reliable itself), but the Shuttle's engines have to fire longer to reach ISS. A "safe haven" is useless if a failure leaves the Shuttle unable to reach it. Regardless of destination the safest approach is to keep a rescue Shuttle or Soyuz ready to fly within a week. The real reason to limit Shuttle flights is to maximize the chances of completing US contributions to the astronaut hotel called ISS. Hubble was never intended as a permanent floating observatory. The follow-on telescope is to be launched in 2010 and will greatly expand on Hubble's capability. There's even a possibility that Hubble will remain functional through 2010 w/o replacing the 3 remaining operational gyro packages. The James Webb space telescope is for IR only, not UV or visible light. There is wide scientific agreement that Hubble should stay in use at least until JWST is operating: http://www.space.com/scienceastronom...on_050121.html |
#2
|
|||
|
|||
![]()
richard schumacher wrote in
: In article , OrionCA wrote: On Sat, 22 Jan 2005 09:27:57 -0600, richard schumacher wrote: http://www.space.com/news/hubble_budget_050121.html "The White House has eliminated funding for a mission to service the Hubble Space Telescope from its 2006 budget request and directed NASA to focus solely on de-orbiting the popular spacecraft at the end of its life, according to government and industry sources." No surprise here. Bush gets all his science from the christian bible. Time to write our congresspeople to direct NASA to save Hubble. All future Shuttle missions must include the capability to reach the ISS in case of a major emergency that precludes re-entry. Hubble is in an orbit that the three remaining Shuttles can't attain and still reach the ISS. Ergo, no Hubble resupply missions are planned. That is an arbitrary choice. A Shuttle mission to Hubble is not significantly more dangerous than to ISS; true, there's no "safe haven" at Hubble (and as we see repeatedly ISS is not all that reliable itself), but the Shuttle's engines have to fire longer to reach ISS. This is not true. Powered ascent for the space shuttle lasts about 8.5 minutes regardless of whether it's going to HST or ISS; the only difference is that the abort boundaries are later on ISS flights due to the high inclination. This *is* a benefit; while a main engine failure at some point in an ISS ascent might result in a risky TAL, for the HST ascent an ATO might be possible. On the other hand, ISS ascent is more survivable with multiple engine failures due to higher availability of ECAL. Furthermore, the shuttle has to burn considerably more OMS propellant to reach HST than ISS due to the higher altitude, so an OMS failure on an HST flight is a bigger deal than it would be on an ISS flight. A "safe haven" is useless if a failure leaves the Shuttle unable to reach it. Regardless of destination the safest approach is to keep a rescue Shuttle or Soyuz ready to fly within a week. Soyuz cannot reach HST's inclination from Baikonur, and the pad at Kourou is not planned to have capability for the manned Soyuz spacecraft (as opposed to the Soyuz launcher). Such capability probably could not be made ready in time to save HST, even if it were allowed by law (and it isn't). The real reason to limit Shuttle flights is to maximize the chances of completing US contributions to the astronaut hotel called ISS. True. -- JRF Reply-to address spam-proofed - to reply by E-mail, check "Organization" (I am not assimilated) and think one step ahead of IBM. |
#3
|
|||
|
|||
![]()
One guy's opinion: As long as a significant extension of the Hubble's operating
lifetime is practical. they should use this as the opportunity to develop the kind of sophicticated robotic systems that will be useful for on-orbit and beyond assembly and servicing of Vision for Exploration components. That means adding that cost to the budget and fighting for it. Matt Bille ) OPINIONS IN ALL POSTS ARE SOLELY THOSE OF THE AUTHOR |
#4
|
|||
|
|||
![]()
On Sun, 23 Jan 2005 13:14:54 -0800, in a place far, far away, OrionCA
made the phosphor on my monitor glow in such a way as to indicate that: NASA, in case you hadn't noticed, is not exactly awash in money. Actually, by any rational measure, NASA *is* awash in money. Unfortunately, it's also awash in largely pointless (at least from the standpoint of advancing us in space, such as ISS) projects that remain politically sacrosanct, that suck up more money than it has. |
#5
|
|||
|
|||
![]()
The thing is, for other sorts of in-orbit assembly we're going to be
able to customize the environment to make them amenable to robotic vision and manipulation. Creating a robot to operate on Hubble will actually require several things which would be significantly more difficult than what would be faced in future in-orbit construction and servicing. |
#6
|
|||
|
|||
![]()
In article ,
OrionCA wrote: What part of NO shuttle mission shall not include a "safe haven" route to the ISS do you not understand? The part that explains how this meaningfully adds to shuttle safety. Note that the CAIB specifically did *NOT* recommend such a requirement. Webb is an IR OPTIMISED space telescope but will have some visible light capability... I don't recall it having any... and it certainly has no UV capability. -- "Think outside the box -- the box isn't our friend." | Henry Spencer -- George Herbert | |
#7
|
|||
|
|||
![]()
OrionCA wrote in
: What part of NO shuttle mission shall not include a "safe haven" route to the ISS do you not understand? That is a NASA "Raising The Bar" initiative, not a recommendation from the Columbia Accident Investigation Board (CAIB). Essentially this means all Shuttle missions shall be to or in close proximity to the ISS from now on. There will be no more quick jaunts to pop a satellite into LEO anymore. There would not be anyway. The shuttle is an uneconomical means to perform such missions. There will be no science missions where the astronauts can't look out a porthole and see the ISS off in the distance, or at least during part of its orbit. Again, that is an internal NASA requirement, not an external recommendation from the CAIB. The CAIB never intended for NASA to cancel all non-ISS missions. Like it or not the ISS and Shuttle programs are wedded at the hip now. That is true, but it is not due to safety (except in the mind of the outgoing Administrator, perhaps). Regardless of destination the safest approach is to keep a rescue Shuttle or Soyuz ready to fly within a week. We only have 3 orbiters left: When we had 4 we could afford to keep one prepped for launch in an emergency - barely. In fact the 5th orbiter was envisioned for just this purpose. Then Challenger blew and we were back down to 4 with a heavy schedule and no budget for a "rescue shuttle". Furthermore, there's no guarantee that whatever breaks on a shuttle mission won't prevent a "rescue shuttle" from launching. Of course, the CAIB did not issue a recommendation for a rescue shuttle either. That is also an internal NASA requirement. Regarding there not being enough orbiters to keep a rescue orbiter on the pad in all cases, this is *somewhat* true. If every shuttle flight were a non-ISS flight, a rescue orbiter would be unsupportable since the rescue time requirements would be tight and the rescue orbits would be too varied. But in the post-Columbia environment, where every flight goes to ISS, a rescue shuttle is somewhat easier since the schedule is slightly more relaxed - the stranded shuttle crew can use ISS consumables - and the next orbiter in the flow is likely headed to ISS anyway. Of course, this also does not apply to the case of a *single* HST servicing mission - it simply means that the rescue orbiter would be pulled from the ISS mission rotation longer. That will be a disruption to the overall ISS assembly schedule, which may or may not be a serious problem, depending on your priorities. Again, of course, this assumes that you consider a rescue orbiter a *requirement* for an HST mission - the CAIB certainly did not. The Russians don't have money for a "rescue Soyuz" - they say they have a spare or two they could prep quickly but it'd been hard as hell. They've started charging for lifting US astronauts to the ISS, have you noticed? They're broke, too. They can't reach HST orbit anyway, and won't be able to do so within the timeframe needed. -- JRF Reply-to address spam-proofed - to reply by E-mail, check "Organization" (I am not assimilated) and think one step ahead of IBM. |
#8
|
|||
|
|||
![]() "richard schumacher" wrote That is an arbitrary choice. A Shuttle mission to Hubble is not significantly more dangerous than to ISS; true, there's no "safe haven" at Hubble (and as we see repeatedly ISS is not all that reliable itself), but the Shuttle's engines have to fire longer to reach ISS. A "safe haven" is useless if a failure leaves the Shuttle unable to reach it. Regardless of destination the safest approach is to keep a rescue Shuttle or Soyuz ready to fly within a week. The real reason to limit Shuttle flights is to maximize the chances of completing US contributions to the astronaut hotel called ISS. What is the basis for this claim about the engines firing longer for ISS? |
#9
|
|||
|
|||
![]() |
#10
|
|||
|
|||
![]() What part of NO shuttle mission shall not include a "safe haven" route to the ISS do you not understand? The "safe haven" dictum was a political decision. What part of "political" do you not understand? If you're saying that an astronaut hotel is more valuable than doing astronomy, then we simply disagree about what is important. |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Robots to rescue Hubble? | Steve Dufour | Misc | 23 | May 6th 04 09:15 AM |
NASA Is Not Giving Up On Hubble! (Forwarded) | Andrew Yee | Astronomy Misc | 2 | May 2nd 04 01:46 PM |
Don't Desert Hubble | Scott M. Kozel | Policy | 46 | February 17th 04 05:33 PM |
UA Scientist Sheds New Lights On Outer Planets With Hubble Space Telescope | Ron | Astronomy Misc | 0 | January 22nd 04 09:05 PM |
Hubble Space Telescope first casualty of Bush space initiative | Tom Abbott | Policy | 10 | January 21st 04 05:20 AM |