Is there a way to save Hubble Space Telescope?

[yoda9999]

Can we somehow move the HST closer to the ISS? That way there would be astronauts always there to service it. And it would be easier for CEV or shuttle to send stuff up to fix it, since NASA wants manned spaceships to be near ISS for safety.<br /><br />Maybe attach some rockets to the HST and gently boost it to the ISS's orbit.

 

[MeteorWayne]

Unfortunately that is not realistic.<br />The amount of enegy required to shift the plane of the orbit would be enormous, and it would take too long (and too much money) to develop a power plant to do that before the Hubble's eventual demise.<br />I'm afraid the best we can hope for is to extend it's life as long as we can in it's present orbit.<br />We will all mourn it's passing.<br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[bushuser]

I know we have been over this before, and understand change of orbital plane is a large energy investment..but has anyone looked at the difference in energy to deorbit HST, versus the energy to move it towards ISS? Either way, there would have be R & D for a motor to be attached at a later time. The only difference is the size of the rocket motor, and the fact that only a single burn is necessary to crash the ISS.

 

[MeteorWayne]

To deorbit is only a few km/sec. To shift the plane is a good part of a full launch, at least 25% of the energy.<br />It could be more, I'll have to try and figure it out. Shuttle_guy, have you any handy figures?<br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[willpittenger]

Since you asked about boosting Hubble to ISS's orbit, I should note that Hubble would not need to be boosted to get there. It would only need a complex series of transfer orbits. The problem with your assumptions is altitude. Of the two orbits, Hubble's should be far higher. It had to be as far as possible from the interference of the atmosphere. Putting it up there also meant that reboosts would happen only when needed. ISS avoids frequent reboosting (that we hear about) by doing its own reboosts and by using sheer mass to resist drag.<br /><br />As for the altitude, Hubble was launched as high as Discovery could take something that heavy. That is far higher (and into the Van Allen belts) than ISS. To reach ISS, the orbiter must burn a lot of fuel to reach ISS's inclination -- and then move to an orbit that allows it to return to one of the three landing sites. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[scottb50]

It would be easier to pick the HST up with the Shuttle, return it for overhaul and put it back in orbit. Two Shuttle launches, but if you put it into the ISS orbit, nearby crew could still be transfered. <div class="Discussion_UserSignature"> </div>

 

[j05h]

The best way to save Hubble is build three more, fly them on EELV and call them the Hubble2 series. It'd cost only slighty more than the servicing mission and give us several visible/IR telescopes. Nothing lasts forever, and the orginal Hubble is definitely starting to wear out. <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[vulture2]

I absolutely agree, and as you can see none of the later generation of space telescopes were designed for any servicing. Using ELVs and putting them in high eliptical or solar orbits solved a lot of problems. The problem with Hubble is that one of the previous NASA administrators accidentally increased the size of the next optical telescope (i.e. the Webb) from 4 meters to 8 meters, adding several years to the development time. IMHO a new 4-meter scope could have been in orbit already. <br /><br />If someday the price of human spaceflight can be brought down to a reasonable level with a real fully reusable vehicle, the equation would change, and maintenance would make sense.

 

[j05h]

Maintenance only makes sense for cis-lunar telescopes. Telescopes in solar orbit would generally be harder to get to, and very very useful. If we could have instruments at 60 or 90 degrees in front and behind Earth, we would open up new vistas for asteroid searches and general astronomy. <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[willpittenger]

You misread my post.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><blockquote><font class="small">In reply to:</font><hr /><p>I should note that Hubble would not need to be boosted to get there. It would only need a complex series of transfer orbits.<p><hr /></p></p></blockquote><br />A transfer orbit requires a boost....i.e. a rocket motor burn.<p><hr /></p></p></blockquote><br />You just stated that any burn is a boost -- even a deorbit burn. I am including in "boost" on those burns which increase the altitude of part or all of the orbit.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><blockquote><font class="small">In reply to:</font><hr /><p>To reach ISS, the orbiter must burn a lot of fuel to reach ISS's inclination -- and then move to an orbit that allows it to return to one of the three landing sites.<p><hr /></p></p></blockquote><br />The Orbiter can not transfer to a ISS orbit from a HST orbit. The max Orbiter OMS delta V for all operations is 1,000 ft/sec. when 13,000 ft.sec is required plus the OMS-1 burn, burns to get to HST and the de-orbit burn.<p><hr /></p></p></blockquote><br />I was talking about when the orbiter launchs direct to ISS. I never tried to explain whether or not the orbiter could reach ISS from the Hubble orbit. In fact, I think that most readers of this thread know that. That was why a Hubble service mission has been in doubt for years.<br /><br />Edit: Corrected typo. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[willpittenger]

Such scopes would also be far more stable that Hubble. Stability is VERY important when when WPF is doing a 6 day exposure. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[willpittenger]

Sorry. Altitude. See corrected post. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[alokmohan]

Can you tell me what is the position of JWT?

 

[erioladastra]

"Such scopes would also be far more stable that Hubble."<br /><br />I assume you mean there would be more continous viewing windows. HST is very stable for long term observing. You can't do a long (i.e., many hours) observation anyway. So you only need to be stable for shorter observations which it is.

 

[willpittenger]

You mean where it would orbit? Out past the moon from what I understand. The ideal place to me would be a planet-sun L4 or L5 point. However, I do not know how much Delta V is needed to get something the size of JWT there. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[willpittenger]

An exposure lasting several days is by definition several shorter exposures, one per orbit. The real problem with long exposures is synching up all of the various exposures. If the telescope is not pointed in the exact same direction for each exposure, you loose that. Remember, the Earth and Hubble's orbit relative to the Earth move each orbit.<br /><br />Yes, a longer orbit would also allow for more observing time per orbit. However, an circular orbit that is simply farther from Earth would also increase the time that the telescope could not observe. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[willpittenger]

I was thinking of how much more fuel would be needed. Sorry if I used the wrong term. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[willpittenger]

So do we have a booster that could get JWT to L4 or L5 for the Sun and Earth (or another planet)? <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[willpittenger]

I take it you do not know the capabilities of the various options either. Have other projects prosposed putting anything similar there? If so, what would they have used? <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[qso1]

http://en.wikipedia.org/wiki/James_Webb_Space_Telescope<br /><br />http://www.jwst.nasa.gov/<br /><br />The above links give a pretty decent explanation of the JWTs launch and mission plans. Last I recall looking, the JWT launch vehicle had not been defined but it looks now as though the Ariane 5 will be the JWT LV.<br /><br />Below are links for the TPF telescope.<br /><br />http://en.wikipedia.org/wiki/Terrestrial_Planet_Finder<br /><br />http://planetquest.jpl.nasa.gov/TPF/tpf_index.cfm <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[erioladastra]

"An exposure lasting several days is by definition several shorter exposures, one per orbit. The real problem with long exposures is synching up all of the various exposures. If the telescope is not pointed in the exact same direction for each exposure, you loose that. Remember, the Earth and Hubble's orbit relative to the Earth move each orbit. "<br /><br />Still not sure I see your point. With detector noise you generally can't observe very long any way, so you have to do short exposures. You also want a little "wiggle" so that you hit different sample diodes on different exposures to remove detector effects, especially on such sharp point spread functions as HST has. (Though there are exceptions depending on the science.) It is trivial to add up numerous images of say the WFPC with the pointing accuracy of HST. If HST was out at L4-L5 I don't think you would see any significant improvement in stability. I am not diagreeing, just don't see it as really that big of an issue. Now, being out a place like that really does open up some nice options of field of view. It will be awesome when Kepler gets up there and stairs at the same point in space continuously. Man, will we get a lot of great data from that. Who cares if we actually find a planet, I'll take all the data they throw away!