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October 17, 2008

More Hubble trouble

Posted: 12:15 PM ET

Engineers at the Goddard Space Flight Center in Maryland have hit a snag in their efforts to bring the Hubble Space Telescope back on-line after a major equipment failure in space last month.

The Hubble Space Telescope. Image: NASA

Hubble's Science Instrument Control and Data Handling (SIC&DH) system went down September 27.  This is the telescope's on-board computer that coordinates commands to the various instruments and then downlinks the scientific data to the ground.

While that computer is off-line, most science observations are at a standstill.

The good news is that the computer was built with a fully redundant back-up channel called "Side B" designed to come on-line in the event "Side A" ever failed.  Hubble team members at Goddard began a complicated process to switch over to "Side B" on Wednesday. This involved sending comprehensive software commands up to the telescope to essentially take control of Hubble's suite of telescopes and other sensors  through "Side B," recalibrate all those instruments which went into safe-mode when the computer went down, start and stop gyroscopes, downlink data, and then check the data quality against some older "Side A" samples to make sure all is square.

Problems cropped up somewhere in that process Thursday night.  We haven't been told yet exactly what happened.  The team is meeting today to discuss a further troubleshooting plan.  We may get additional details later when that meeting ends.  I am told they don't expect the issue to be resolved today.

As noted, the switch-over process is extremely complicated, and it is probably to be expected that they would hit some sort of snag.  Hopefully, they will work through it in the coming days and science operations can resume soon.

Even if the switch-over to "Side B" fails (and it is far too soon to go there), the Hubble design team had the foresight 20 years ago to build a spare SIC&DH system, which has been warehoused at Goddard all this time while the original instrument perked along just fine.  Astronauts are scheduled to conduct a fifth and and final Hubble servicing mission in the February time frame, and will almost certainly remove and replace the malfunctioning computer with the spare.   That mission was supposed to fly this month, but was postponed when the failure occurred to give the ground teams time to check out the spare and astronauts time to train on the removal and replacement procedure (which is apparently a relatively straightforward, two-hour spacewalk task).

If there is any silver lining to this whole thing,  it's that the failure happened before the servicing mission - while there is still the opportunity to fix it.   Imagine the disappointment if it had happened right after the astronauts returned!

I'll update later today if and when I get more information.

–Kate Tobin, Sr. Producer, CNN Science &  Technology

Filed under: Hubble Space Telescope • NASA • Space

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Larian LeQuella   October 17th, 2008 12:20 pm ET

Good luck NASA! The Hubble is a fantastic piece of machinery that deserves to be kept functioning as long as possible. I look forward to updates!

Franko   October 17th, 2008 12:42 pm ET

The 386 processor, produced since 1986. Hubble launched 1990.
Who uses a 20 year old computer nowdays ?
Quad core, put 4 laptops on four wireless routers.
All kinds of redundancy

Ray G.   October 17th, 2008 1:27 pm ET

I believe I read somewhere that the telescope is still able to perform valuable astrometry measurements while the other instruments are down. Among other things, Hubble astrometrics are used to help understand the nature and distribution of dark matter in the universe.

It all a big lie   October 17th, 2008 2:57 pm ET

It's all a big lie.
There is nothing out there.
NASA is just one big Jobs Program for engineers 😦

Larian LeQuella   October 17th, 2008 4:16 pm ET

From Bad Astronomy: The HST486 (replacement to the DF-224) computer that manages the spacecraft pointing control and other subsystem tasks safed, as it is supposed to do, the NSSC-1 (NASA Standard Spacecraft Computer 1) that normally interfaces with the science instruments, and then the SI’s themselves at 21:14 UT. The two computers “talk” to each other across what is known as a “Processor Interface Table”, or PIT. A continual “handshake” (PIT toggle) between the two computers is expected. If the DF-224 does not get that handshake it presumes the NSSC-1 may have a problem and, through a predefined sequence of inter-computer commands puts the NSSC-1, and then separately the HST Instruments into a “safe” configuration. Of course, then, the “stored command plan”, which was on a path for recovery to restart science, carried out by the NSSC-1, is suspended.

What caused the loss of the PIT toggle? That is still under investigation. But, what is known is that the redundant “Command Unit/Science Data Formatter B”, part of the Command and Data Handling (C&DH) unit side A, that failed after 18 years is apparently fine. In fact, the NSSC-1 memory after it was safed was successfully dumped to the ground through CU/SDF-B. A preliminary analysis of that memory dump points to a “potential problem” (emphasis is on potential, as this is quite early in the investigation) in the Central Processor Module (CPM) on C&DH Side B. But unclear if that is a potential H/W, configuration (remember everything was just switched over to Side B with a lot of reconfiguring), or S/W “problem” – so I would not jump to any conclusions ahead of the good folks at Goddard looking at this carefully and methodically.

In the short term… As the CPM is redundant – AND can be cross-strapped- (in a side A/B hybrid configuration) by ground command, Goddard is in the process of moving contingency operating procedures to affect that cross-strap using the high-fidelity Hubble simulator (the VEST “Vehicle Electrical and Test” facility). That may already have been done as I write this, and thus (presuming that ground test is successful, as I would expect it to be), the COP would be available to do the same on-orbit if further diagnostics and analysis indicate a side A/B hybrid would (for now) take care of the problem.

The above is an “unofficial” explanatory status. Look to NASA for the official word.

Franko   October 17th, 2008 8:34 pm ET

The mirror and mechanicals are still viable.
From computer stone age specialists,
A gift for the ages. A space age Stone Henge ?

Sink a ship to make a Coral Reef.
Boost a Hubble, the theme of attraction,
For a space history vacation.

Wayne Pigeon, Sterling Heights, MI   October 17th, 2008 10:47 pm ET

Hang in there, NASA. The Hubble project is the most-spectacular one in history, next to the 1969 moon landing.

KAISER   October 18th, 2008 6:22 am ET


Bob S.   October 18th, 2008 6:52 am ET

HST was built in the early 80s (and has many electronic parts from the 70s). It was to have been launched in 1986 right after the Challenger mission so it sat in storage for a few years.

Although the first Pentium was released when the 486 was chosen as the replacement for the DF-224, there were no Pentiums qualified for radiation susceptibility at that time. Larian is correct – each subassembly within the SIC&DH has an A side and a B side and various combinations of A and B can be selected. A workable string will be determined (my prediction!) and HST will be back and running shortly.

Anthony   October 18th, 2008 11:36 am ET

It seems to me that since Bush announced his change in priorities the support for Hubble is not as strong. We are now checking the edge of the solar system? Did voyger leave the solar system yet?

Marilyn   October 18th, 2008 8:48 pm ET

I want to commend Kate Tobin for an excellent article about a technical subject. I remark about it because I don't expect this much actual information from CNN. The conversational tone (being a blog) and level of detail was just right. It gave me the information I wanted in an accessible way. I am familiar with spacecraft data systems design and how Goddard engineers work a problem, and this post conveyed it very well.

HST is a treasure. I hope functionality can be restored, and HST can continue to help humanity discover the wonders of the universe.

Jim in MA   October 18th, 2008 8:50 pm ET

I really think it is funny how you modern day "techno snobs" (Franko) minimize the great scientific accomplishments of the past. You may be able to surf the web with your duo core processors, but I have not seen any of your generation walking on the moon yet. Even the Chinese are out stripping you guys in scientific knowledge. Keep on surfin' and gamin' DUDE.

S Callahan   October 18th, 2008 10:07 pm ET

I'll say a prayer for NASA./Hubble....only a few more weeks and funding will increase for NASA....hang in'll all work out.

Franko   October 19th, 2008 1:01 am ET

S Callahan; "I’ll say a prayer for NASA./Hubble"

Please be selective, and do the oppisite, not a prayer, but a curse !
For the NASA Climate Dogma - Mislead, fool you for your own good
"NASA Chief: Global Warming Treated Like a Religion"
"embroil my agency in a controversy in fight that we don't have a dog"

Carbon taxes, predicted to rise, drowning the world economy.
Thank you NASA, and others of the Commie Eco Climatist Religion,
Death by a thousand cuts, taxation version . 1/2 dead the goal ?
Pray for NASA, and you are a part of the problem.

R. Morton   October 19th, 2008 4:39 am ET

To "its all a big lie."
Are you really that small minded to believe that? Perhaps you are just uneducated and upset with your lot in life! So sad. Hubble has given us all a glimpse so far back in time and that is just a small portion of it's work so far. And no, I am not a space tech!

Les Leider   October 20th, 2008 8:35 am ET

There are two launchpads capable of launching the Orbiters. With Atlantis moving today, Nasa is reportedly beginning to alter one launchpad to handle the Constellation program. With only one launchpad for Orbiter missions, how can we return to the Hubble when Nasa requires another Orbiter to be ready to go?

Are we really going back to the Hubble?

Nelson Colorado Springs Co.   October 20th, 2008 10:06 am ET

NASA the Hubble is a fantastic piece of machinery that needs to be updated with new computer and soft ware then put back in orbit to continue the mission of looking to space. The Hubble launched 1990 that a long time ago. Keep up the good work. forward to updates!

Jimbo   October 20th, 2008 11:19 am ET fight without a dog? Who are you to talk give no hope and sound like Michael Vick....
Simplicity at its best...they can and will fix it in February when the time comes. Even YOU could use a good "fixing". Think positive and keep your head screwed on tight good thing will happen to those who WANT it to happen.
Even if the world comes to an end, we will all be fixed appropriately ...when that time comes as well.

Brenda Eve   October 20th, 2008 12:07 pm ET

Keep the Hubble going until the new telescope is deployed in 2010!~ What a scientific treasure it has been!

Spell Check   October 20th, 2008 12:29 pm ET

This news story contains a spelling error: "and it is far to soon to go there", should be "and it is far too soon to go there".

Larian LeQuella   October 20th, 2008 3:33 pm ET

Names that end in "o" on this forum have the most interesting posting style. 🙂

Spell Check   October 20th, 2008 4:59 pm ET

The spelling error is now corrected.

Franko   October 20th, 2008 7:44 pm ET


NASA is into all kinds of things, Distacting. From Job #1, attention is stolen
Shuttle crashes, probe crashes, culture clashes,
Measurements are challenged by slugs

But on climate, you have to accept the NASA Dogma.
Hence the secret, code word "dog"

Brad   October 22nd, 2008 3:12 pm ET

People have to remember, money spent on space programs doesn't dissapear into space. It stays right here on Earth providing research and new technologies. Every time we plan a mission, we learn. That's what it's all about.

Ashley   October 23rd, 2008 7:08 pm ET

How came people always have to talk abput the BAD

Franko   October 24th, 2008 5:36 am ET


Most conversations reduce to;
Are you there ? Please Confirm.
This is good or this is BAD

The BAD is emphasized, is interrupt -1 -*- Safety is Job #1 -*-
Microprocessor, that does not process, with top priority, not a survivor

R. Morton   October 25th, 2008 3:49 am ET

Definitely true about the "Os". What is their problem.? Here is hoping that Hubble gets a new lease on life. We have learned so much since it's inception The more we learn, the more we gain. Go NASA! Too bad the "Os" don't get it!
I could say more but why bother. Some people just don't get it!
At all !
I feel sorry for you. Happy Trailer Life! And by the way... Good luck at
I'm sure that is what you are hoping to retire on!!!

R. Morton   October 25th, 2008 4:00 am ET

Are you ill?

Franko   October 27th, 2008 2:21 am ET

R. Morton; "Some people just don’t get it! ... At all !
I feel sorry for you. Happy Trailer Life! And by the way…
Good luck at Bingo!!! ? "

As I look out, with my telescope to the Universe, the trailer window.
Hubble and I, spy the same sky.
Neither I, nor the Hubble, has yet, identified Niburu, coming in 2012.

R. Morton gets it.
While most Earthlings, Hubble scientists included, are trying to figure it

I would be willing, to donate some of my Bingo winnings
Not to the Hubble, but to a very deep and large InfraRed telescope,
(Alas, IRAS and other InfraReds, were just too small)
So I know. not only the year, but also,the hour, of the Nepharin.

R. Morton   November 1st, 2008 5:17 am ET

Thanks Franko;
How about we all contribute a very small percentage of what we earn. In time it would add up so that we could afford to learn what we need to. It's a big universe out there. I'm keen. Let's do it.

Fritz Anderson   November 4th, 2008 8:59 pm ET

For lack of a better place to put my comment. i wanted to comment on the halogram presentation, very hopefull that technology can and will make a crucial difference in the future of the american economy. And needless to say that obama with his success via technology in this campaign will be the choice to encourage and support this drive.

R. Morton   November 8th, 2008 2:54 am ET

To Fritz A.
CNNs naming the effect a "hologram" is quite a laugh among us in the broadcast industry. It is nothing more than a "Key" with a mask that follows the fill item, and not very well at that. I assume that it was Wolf Blitzer, Part of the "best political team on television"
( Boy am I sick of hearing that every 2 minutes!) that came up with it. I hope some of you watched the excellent coverage provided by ABC,CBS,NBC,CBC and BBC. Wolf, let some of the hot air out of your head and give us all a break. You are not, and never will be Walter Cronkite.
Sheesh! Even Jack Cafferty was embarrassed by your constant references to the best team slug. Go Jack!
Carry on Wolf, but come down to earth, Please!
Good luck to President elect Obama. I'm a Canadian, and the election was followed very closely among my friends up here in the colonies.( CANADA) Also, good luck to the USA. The world needs you.
RPM & Chester the dog!

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