New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: As a reader of NewMars forum, we have opportunities for you to assist with technical discussions in several initiatives underway. NewMars needs volunteers with appropriate education, skills, talent, motivation and generosity of spirit as a highly valued member. Write to newmarsmember * gmail.com to tell us about your ability's to help contribute to NewMars and become a registered member.

#26 2021-07-04 19:41:18

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: STS-125 Atlantis Hubble SM4 servicing mission

https://en.wikipedia.org/wiki/Hubble_Space_Telescope

There was a topic that talked about the alternatives to flying shuttle and getting a Hubble replacement on line using the new equipment that was later used to make the final repairs back in 2009..

Since that mission needed to have a second shuttle on the launch pad for safe return if something had happened to the other.

Aside from creating the electronics and the housing for all of them the most critical item is the mirror which was botched and needed to have corrective lenses sent up for the first repair...

Offline

#27 2021-07-04 19:48:33

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: STS-125 Atlantis Hubble SM4 servicing mission

For what it's worth, the Starship could probably reach Hubble, if it were refueled on orbit.

That would be a neat way to get Uncle Sam to pay for the mission.

The equipment to perform the service need not be carried inside the Starship.

It could be carried to orbit as a separate payload, and then mated to the Starship that is going out to Hubble.

Heck ... that equipment could be permanently attached to Hubble.  There'd be no need to bring it back.

(th)

Offline

#28 2021-07-04 21:53:28

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,781
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

Dragon could service Hubble. Falcon 9 might not be able to launch it high enough, would require Falcon Heavy. That means they have to human certify Falcon Heavy. Should have been done by now. Equipment (replacement parts and tools) could be carried in the trunk.

If SpaceX doesn't want to use Dragon to fix Hubble, then I'm sure Boeing would be willing to accept money to use Starliner launched on Atlas V. Starliner doesn't have a convenient trunk to store replacement parts, but I'm sure they would be willing to add anything for enough money.

Offline

#29 2021-07-05 06:48:40

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: STS-125 Atlantis Hubble SM4 servicing mission

For RobertDyck re #28

A detail is that Dragon does not have an air lock ... Like Gemini, everyone would have to suit up during EVA's.

It's not a show stopper ... just an aspect of the flight to take into consideration.

There is no need to be concerned with aerodynamics for equipment to be carried along, if the equipment (or supplies) are brought to orbit separately and attached to the servicing vehicle after it reaches LEO.

A permanent repair station could be sent to Hubble along with the human capsule.  The permanent repair station could have an air lock to which the Dragon would secure itself.   The technical capabilities of the United States have improved since Hubble was launched, and the mirrors are fine.  Everything else can be replaced every few years.

Someone (?kbd512?) suggested that Hubble is a global treasure ... is it worth considering a draft on other nations to help with expenses?

(th)

Offline

#30 2021-07-05 07:46:27

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,781
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

tahanson43206 wrote:

A detail is that Dragon does not have an air lock ... Like Gemini, everyone would have to suit up during EVA's.

Same with Apollo 9. Astronauts who didn't leave the vehicle could have sheltered in the LM, but I don't think they did.
3A7B81FEE0DD42458CC8784449C0AFAD.jpg

Offline

#31 2021-07-05 08:06:57

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,781
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

tahanson43206 wrote:

Someone (?kbd512?) suggested that Hubble is a global treasure ... is it worth considering a draft on other nations to help with expenses?

Hubble is operated by the Space Telescope Science Institute. From their website... "We are the Space Telescope Science Institute in Baltimore, Maryland, operated by the Association of Universities for Research in Astronomy." The Association of Universities for Research in Astronomy (AURA) is a consortium of universities and other institutions, it has 47 member institutions in the United States and 3 international affiliate members. International affiliate members: Leibniz-Institut für Sonnenphysik (KIS), Pontificia Universidad Catolica de Chile, Universidad de Chile. The first is based in Germany, the other two in Chile.

Offline

#32 2021-07-05 09:22:15

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,423
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

In order to do any sort of repair,  an astronaut must exert forces.  The reaction to those forces has to be stabilized by a physical connection between the Hubble and whatever vehicle comes to service it.  With the shuttle,  that was the manipulator arm that reached out and "grabbed" Hubble.  That same manipulator arm also served to stabilize the astronaut himself while he exerted those forces. 

So,  when you think about it in terms of undergrad F=ma mechanics,  what made the shuttle such a good space truck for these repairs was not so much its cargo bay,  but its manipulator arm.  The key features for making such repairs are thus a manipulator arm,  a cabin in which to work in shirtsleeves,  an airlock for the astronaut (or astronauts) who goes EVA,  and some propulsion to move about in orbit and rendezvous with the item to be repaired. 

It did not make good economic sense to have to launch all this stuff every time,  which is what we did with shuttle.  Having such equipment stationed on-orbit,  and using it many times,  makes a lot more sense.  All you do is send up a crew and some propellants when you have a repair mission. 

I first proposed such a thing a decade ago.  You can find it on my "exrocketman" site as "End of an Era Need Not Be End of a Capability",  posted 2 August 2011,  just as the shuttles were retired.

Dragon alone cannot do the Hubble repair mission. It does not have a manipulator arm to perform the stabilization function,  or any place to carry one.  It also has no airlock,  which is quite inconvenient.  Same is true of Starliner.  Or Orion,  for that matter.  Or Soyuz,  or Shenzou.  Or anyone else's spacecraft designs. 

And without a manipulator arm,  Starship cannot perform the repair mission,  although a cargo Starship might capture and contain Hubble,  locked down somehow within its cargo hold.  But where would the repair crew be,  on a cargo Starship?  And if you do it that way,  you are back to sending up all the hardware for every mission.  Just like shuttle.

But the requisite repair vehicle could be easily launched and docked together,  and left in orbit.  The article I posted a decade ago illustrates that concept quite clearly,  and recommends 3 be posted on-orbit,  in 3 different orbits:  (1) in the highly-inclined ISS orbit,  (2) in the more eastward orbit of Hubble,  and (3) in polar orbit.  That way we have a repair capability for anything up there but geosynch,  any time we need it,  and without the massive delta-vee requirements for huge orbital plane changes.

Geosynch is a special problem,  because that is out in the inner Van Allen radiation belt.  Shielding a repair crew there would be difficult.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

Offline

#33 2021-07-05 10:15:17

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,366

Re: STS-125 Atlantis Hubble SM4 servicing mission

Instead of repairing a 30 year old telescope, difficult to repair as stated earlier in this thread, a suitable replacement could be carried to orbit by either a Falcon 9 or Ariene 5. Falcon 9 would be less expensive but a size increase would make for a smaller telescope than could be carried by the Ariene 5 due to a smaller fairing size.

Offline

#34 2021-07-05 11:13:54

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,781
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

Hmm. Rather than latch Hubble to Shuttle's cargo hold and use the arm for astronaut foot restraint, why not attach a small arm to Hubble's grapple point, with foot restraint at the other end of the arm. No Shuttle. Just something attached to the telescope that can hold astronaut's feet.

Hubble is 14 feet wide (4.2m) at the back. There are 2 grapple points, one on each side, behind the solar panel pivot. To access an equipment bay 90° around the circumference from a grapple point, say arm is ½ metre from Hubble due to grappler, so 4 metres of arm from grapple to foot restraint. If the arm has an elbow joint so it can fold in half, that would easily fit in the SpaceX trunk.

When NASA was planning to build US space station Freedom, Canada committed to build a satellite service module. A full-size module. That was cancelled when Freedom was cancelled. The problem with that is it would be attached to a station in LEO. Most satellites are not in LEO, and those that are in low orbit are not in the same orbit as the station.

Looking at the side hatch of Dragon. Shuttle's EVA hatch was 40" diameter. There was a flat spot for the hinge, so the width was only 36". Dragon side hatch appears to be 0.842 meters wide at the top, just before it curves to the top edge. That's 33". And 1 metre (39.37") wide at the bottom, 1.158 metres (45½") tall. Could an EMU suit egress through that? Just like Apollo 9?

Also remember both Shuttle and ISS used 1 atmosphere pressure. Astronauts had to prebreathe oxygen for 17 hours prior to EVA to flush out nitrogen. Apollo used 5.0 psi pure oxygen. A7L suits used 3.7 psi pure oxygen. EMU uses 4.3 psi pure oxygen, to reduce the difference between cabin pressure and suit pressure. We wouldn't want to develop a new suit, but Dragon would not have to be pressurized to 1 atmosphere. It could depress during ascent like Apollo did. That would mean time between launch and rendezvous with Hubble would be the prebreathe time.

Offline

#35 2021-07-05 11:24:04

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: STS-125 Atlantis Hubble SM4 servicing mission

For RobertDyck re #34

It's fun to watch your debate with GW Johnson here ... I think that serious thought (such as yours) should (and hopefully will) be given to funding a Hubble Restoration mission, using modern technology.

Your points about Dragon possibly being able to serve as a cabin for this venture seem strong enough to withstand casual review.

***
For GW Johnson .... how's your energy level these days?  It is possible for ** someone ** to serve as a sparkplug for developing public consensus around a proposition to carry out a Hubble Restoration mission.

We have a crew in the White House right now willing to spend on worth while projects, and this sure looks like one.

Would you be willing to compose a letter to appropriate leadership advocating such a project on an "emergency" basis, ie, ahead of the Moon project NASA is currently focused upon?

(th)

Offline

#36 2021-07-05 11:24:46

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,781
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

Starliner uses its service module for abort. So cargo would have to be a separate module. Perhaps launched on a single launch vehicle, like Apollo CSM and LM, with Starliner turning around and docking it's nose to the mission module the same way Apollo docked to LM. You wouldn't want Starliner or it's mission module to grapple Hubble, that would require 2 arms: grapple and foot restraint. Like a suggested for Dragon, one arm that attaches to Hubble's grapple point, other end has foot restraint. Just hover the spacecraft beside Hubble. You may be tempted to put an airlock in the mission module, but that adds unnecessary complexity. Just decompress the whole capsule like Gemini or Apollo 9. Yes, that means all astronauts will have to suit-up. But how many astronauts do you need? Why would there be any astronauts not working the repair? Any astronaut left in the capsule could maintain spacecraft position, but automation can do that now. If any are left, they would have to be able to rescue EVA astronauts. Could Starliner's new in-capsule suit be used for an emergency rescue? Could SpaceX suit?

Offline

#37 2021-07-05 11:57:33

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,781
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

Tom, NASA does accept unsolicited proposals. But that assumes the proposer is offering to do the work. I'm just some guy working out of my home. I'm a computer software developer, I could brag about my resume and past job titles, but I've worked as a computer technician the last 13 years. This would require major contributions by SpaceX or Boeing. And who's going to build the little arm? MacDonald Dettwiler and Associates (MDA) built CanadArm2, the arm for ISS, but they haven't done any space arm work in a while. Let's see, MDA Space Systems still has a website. Hasn't Canada offered to build an arm for the Lunar Gateway? I guess they're still in business.

We've debated space engineering on this forum or the previous since the Mars Society was founded. Usually just arm-chair quarterback type thing. The Mars Society did lobby Congress to save Hubble. That worked. We've advocated larger budgets for NASA, and that got NASA's attention. Due to that, NASA likes us. But you want to get serious? Yes, I did try to seriously bid on a couple NASA contracts. The fact I don't live in the US was the problem both times. What are you proposing?

Offline

#38 2021-07-05 12:17:50

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,781
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

Oldfart1939 wrote:

Instead of repairing a 30 year old telescope, difficult to repair as stated earlier in this thread, a suitable replacement could be carried to orbit by either a Falcon 9 or Ariene 5. Falcon 9 would be less expensive but a size increase would make for a smaller telescope than could be carried by the Ariene 5 due to a smaller fairing size.

Due to the altitude and mass, Falcon 9 could not do it. Falcon Heavy would be more than enough. Excess lift capacity means boosters could be recovered.

Hubble was originally designed so it could be brought back in the Shuttle cargo hold, serviced on the ground, and re-launched. Problem was some people can't think in terms of maintaining existing equipment, so if Hubble were ever brought down, it would never be launched again. Because of that, in-space servicing was necessary. That and some people had an issue with Shuttle returning with significant cargo mass. Even though it was originally designed to do that.

Today many astronomers are so obsessed over their current research project that they can't see anything else. They can't see the value of imaging objects within our solar system. So I don't think anyone would build a new telescope capable of doing what Hubble can do.

Offline

#39 2021-07-05 14:29:53

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: STS-125 Atlantis Hubble SM4 servicing mission

For all who might be interested in supporting another Hubble mission (in one of the many forms contemplated) ...

If an idea arrives at a favorable time, it can gather momentum until it becomes reality.

If the idea is starting to percolate here in this (admittedly forward looking) forum, it is probably beginning to percolate in other realms.

If anyone in the readership (member or not) is willing to write emails, text messages or perhaps (gasp) a physical letter, here is an opportunity to add to whatever momentum may already be building.

(th)

Offline

#40 2021-07-06 12:19:36

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,423
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

Tom:

I added an update to the old posting "End of An Era Need Not Be End of a Capability" from August 2011 on "exrocketman".  It's an update that explores the use of vehicles that have become available since then,  plus what I have uncovered for lower-pressure space suits.  Between the verbiage in the original article and this update,  I have essentially drafted the document you suggested.  It suggests how to go about adding an on-orbit satellite repair capability. 

I came to the conclusion this should be done with "new space" contractors.  This is not something that can be strung out as a long,  huge government program,  and it certainly cannot be successful if used as corporate welfare for "old space".  Whether this should go to NASA or Congress first is an up-in-the-air question.  But I am pretty sure (1) that Hubble's mirrors and corrective optics are an asset worth saving,  regardless of the instruments hooked up to them or the avionics running the show,  and (2) we are going to lose that asset pretty soon precisely because 30+ year old electronics is failing in the harsh exposures to space.  No surprises there.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

Offline

#41 2021-07-06 13:01:48

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,366

Re: STS-125 Atlantis Hubble SM4 servicing mission

This is really a case for a cost-benefit analysis; whether the cost of a space launch and space walks to upgrade and repair the Hubble are the same as a replacement without the hassle of space walks  Hubble's primary mirror is 98" in diameter, and whether or not the U of A mirror lab could make a new telescope with larger mirror, more sophisticated instrumentation and control computers reasonably is my question. I think Falcon Heavy could lift a telescope inside their 5 meter diameter fairing, as could an Atlas V. A Falcon Heavy launch would undoubtedly be far less expensive than the Atlas. By my calculations, a 175" diameter mirror telescope could probably be built to fit my proposed launch system(s). Such a telescope would collect about 3.2 x the light gathered by Hubble, and is more than a stellar magnitude fainter capability.

Last edited by Oldfart1939 (2021-07-06 13:21:17)

Offline

#42 2021-07-06 13:07:04

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: STS-125 Atlantis Hubble SM4 servicing mission

For GW Johnson re #40

Thanks for your report on update of your earlier work, and for your confidence that a decision to restore the Hubble would be technically feasible.

The social mechanism for achieving success with your vision is the challenge and opportunity available to members of this group.

We have two active members from Texas, so a senator each would be the right ratio.

I have two senators of opposite parties, but conceivably they could agree on a project like this.

We have a resident of New Hampshire and that state has two senators.

I'm not sure about other members, but if we just start with those six, we have an equal number of Democrats and Republicans.

From my perspective as a potential coordinator/cheerleader for this initiative, I see the following as needed to put this into motion:

1) Can you/would you be willing to convert your work into a proposal suitable for Senatorial review?
2) kbd512 ... would you be willing to forward the proposal to a Senator of your choice?
3) SpaceNut ... would you be willing to forward the proposal to the two ladies currently representing your state?
4) I would be willing to forward the document to my two Senators

All US Senators accept communication via the web site, so I would suggest the message be short and include a link to your blog post.

For this purpose, if you are willing, you could ??? create a special blog post that would be super easy to find.

It is remotely possible the Mars Society might be willing to provide a place for the document on their servers.

It's been a while since the opening document on the NewMars site has been updated.

I believe it still refers to air and water at Mars.

Potentially that document could be allowed to step to #2 position if your document is accepted for #1 position.

Let's aim for a decision Go/NoGo within the month of July.  That should be enough time.  We might be able to work through this more quickly.

If anyone else in the membership with posting privileges would like to help out, please let us know.

Edit#1: Physical letters to US Senators are more work to create and send, but they have much greater visibility because physical mail is less common now.

(th)

Offline

#43 2021-07-06 16:03:48

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,423
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

Tom:

Kbd512 and I are both Texas residents.  He lives in Houston,  I'm rural outside Waco a ways.  That's Cornyn and Cruz for the both of us.

I would be willing to lay out a new version of the satellite repair vehicle article,  if you think that is needed.  It's no problem to post such a thing on "exrocketman". 

But,  this process might not go as fast as you might wish,  if I do it. 

I'm going in for a colonoscopy late this week,  and will probably end up with a surgery date afterward.  My wife consults her surgeon middle of next week on my birthday,  at which point her cancer surgery will likely get scheduled. 

I'm turning 71.

Now,  OF39 is of the opinion that Hubble should be replaced,  not repaired,  and there is a great deal of merit to that. 

We as a group have not yet reached a consensus on that issue.  The issue is really more about timing than cost,  I would venture to argue.  If we repair Hubble,  we need to do it fast,  before the orbit decays.  Maybe it won't,  but Skylab's certainly did.  A repeat of that debacle is NOT an acceptable outcome.

If instead we replace Hubble,  it will inevitably take some years to go operational.  If memory serves,  just the grinding of Hubble's mirror took 2-3 years,  and even then they got it wrong,  and didn't find it until after launch.

I would suggest we come to a consensus on this before contacting senators or anyone else.  My own take is that this goes way beyond just Hubble.  I was writing about establishing a real satellite repair capability in space,  with 3 or more "repair trucks" stationed on-orbit. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

Offline

#44 2021-07-06 17:22:12

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: STS-125 Atlantis Hubble SM4 servicing mission

For GW Johnson .... re #43 and your family's health challenges ...

There are some who would argue that at 71, you are ** just ** edging into territory where wisdom is thought to occur.

However, in order for the world to see the benefits of any wisdom you may have to impart, we need you (and your wife) to be hale and hearty for years to come.

Hubble's orbit is quite high (compared to the ISS for example) so it won't be dropping soon.

About the Hubble Space Telescope | NASA
https://www.nasa.gov
Dec 18, 2018 — This photograph of NASA's Hubble Space Telescope was taken on the fifth ... Low Earth Orbit: Altitude of 340 miles (295 nautical miles, or 547 km), ... of distant, faint objects, Hubble must be extremely steady and accurate.

I am in favor of the full flowering of your idea for a package to be permanently attached to Hubble, suitable for servicing over the next century and beyond.  The package you design could (and I think should) include a booster capability to insure the Hubble rises in orbit (if possible) or at least stays where it is.  A steady ion engine boost, using solar power as the energy source, might be a good fit for the situation.

This group may not be able to achieve consensus on anything, unless you select the team you want to help with the outreach effort.

While we wait for GW  and Mrs. Johnson to visit with their respective health care providers, and to deal with the regimen of recovery they prescribe, it is possible for the members of this group with posting privileges to weigh in on the relative merits of the proposal from GW Johnson, the one from OF1939, and any others that may be brought forward.

I note that we still have over 7,000 spammers with posting privileges.  While SpaceNut is moving as rapidly as he can to reduce that number, a member of that group could show up to lend a hand, instead of selling useless or harmful products and services.

(th)

Offline

#45 2021-07-06 17:44:31

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,781
Website

Re: STS-125 Atlantis Hubble SM4 servicing mission

Skylab's orbit was:
Perigee altitude    269.7 miles (434.0 km)
Apogee altitude    274.6 miles (441.9 km)
Orbital inclination    50.0°
Orbital period    93.4 minutes
So damn near what ISS is today. By the way, those are statute miles (normal miles), not nautical miles. They had a certain number of months to reboost before orbit decayed. Rather than using Saturn 1 or 1B to do it, NASA focused on completing Shuttle. But Shuttle wasn't ready in time.

Hubble's orbit: (Wikipedia)
Perigee altitude    537.0 km (333.7 mi)
Apogee altitude    540.9 km (336.1 mi)
Inclination    28.47°
Period    95.42 minutes

A 2015 article by space.com cited 353 miles (568 km) so it is falling. But it'll be a while yet.

Hubble was first launched 29-April-1990 by Shuttle mission STS-31. Orbit was so high that engineers were worried Shuttle might not be able to return safely. But it did.
Perigee altitude    613 km (381 mi)
Apogee altitude    615 km (382 mi)
Inclination    28.45°
Period    96.7 minutes

Again, that means Hubble's orbit is decaying, but it'll take a while before it drops to the same altitude as ISS, and more time to de-orbit.

Offline

#46 2021-07-06 19:24:40

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,366

Re: STS-125 Atlantis Hubble SM4 servicing mission

I've read the opinions of other regular posters here in this forum, and yes, repairing of Hubble has a lot of merit. But as GW has pointed out, Dragon capsule doesn't have an airlock for astronauts to suit up for EVAs. This in itself is a major strike against a repair mission, as a manned flight to visit Hubble would probably require using a Falcon Heavy launch at some $93 Million. The WFIRST mission is still simmering along as an IR telescope, but having an instrument in visible light and with UV capability is currently absent the NASA planners. What's really needed is a price tag and production timetable for something suitable as a replacement. NOT some segmented folding mirror monster, but a straightforward but larger aperture version of Hubble.

Added here as a P.S.: I'm suggesting a KISS approach. Hubble has already exceeded it's projected lifespan by an order of magnitude. I'm a great admirer of the work it has accomplished, but as it's going into it's "old age," and on the way to becoming an antique--I'm thumping for an upgraded replacement.

Last edited by Oldfart1939 (2021-07-06 19:29:30)

Offline

#47 2021-07-06 19:39:29

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: STS-125 Atlantis Hubble SM4 servicing mission

A search has lead to 2 posting to read on GW's blog site
https://exrocketman.blogspot.com/2014/0 … ility.html

https://exrocketman.blogspot.com/2015/01/

The telescope was designed with module draws to be replaceable but is the problem in the internal connection wiring and not the electronics of the draw?

Shuttle also had to bring with it a holding cradle if I recall to be able to latch onto it so that work could be done with in the cargo bays door opening.

Any mission should also bring a boosting tug to bring the telescope back into a higher orbit.

It takes many years to make a new mirror of the size that we would need plus lots more time for other stuff so if we have 6 years to get this done that is with in the rescue period but if its not going to be in a good location as its falling out of orbit faster than that, plan b is to replace it at that point.

Offline

Board footer

Powered by FluxBB