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Saturday, November 6, 2021

Hubble Space Telescope is Offline Again

You might remember that the Hubble Space Telescope (HST) went into shutdown in June and was inoperable until mid-July before being revived on backup hardware.  The problem was ultimately tracked to a power supply problem in the primary computer and switching to the backup resolved that.

NASA announced Monday that HST's science instruments went down at the end of October and the telescope has been unusable since then.  

The instrument package on the Hubble uses an internal synchronization signal to ensure that everything registers at the same time, allowing instruments to respond to commands in the proper order. On October 23, one of these synchronization signals failed to register, causing all the scientific instruments to enter safe mode. A simple reset of the instruments got everything working again.

But on October 25, the scientific instruments registered the loss of multiple synchronization signals, and all of them re-entered safe mode. Given the repeat and apparent escalating nature of the problem, NASA has left the instruments in that state since.

The HST's own web site contains a little more information, just adding a few details.   

Over the weekend of Oct. 30, the team prepared to turn on parts of the Near Infrared Camera and Multi Object Spectrometer (NICMOS) instrument to collect data on this issue, allowing the team to determine how frequently this problem occurs. Installed in 1997, NICMOS has been inactive since 2010, when the Wide Field Camera 3 became operational. NICMOS allowed the team to use an instrument to collect information on these lost messages while keeping the active instruments off as a safety precaution. Since NICMOS was recovered on Nov. 1, no additional synchronization messages have been lost.

The team is now taking steps to recover Hubble’s Advanced Camera for Surveys (ACS) instrument from safe mode and start collecting science with that instrument at the beginning of next week. The team will make the decision on Sunday after analyzing the latest data. If a lost message is seen before then, the decision to activate ACS will also be revisited. The team is proceeding cautiously to ensure the safety of the instruments and avoid additional stresses on the hardware. Therefore, only ACS will be used in this capacity next week. ACS was selected as the first instrument to recover as it faces the fewest complications should a lost message occur.

That appears to be the extent of what's known at this time.  The Hubblesite.org website contains a link to a NASA site, which links back to the same article on Hubblesite.  

Let's be honest.  I'm just guessing, but Hubble has been in space 31 years and all electronic components are going to age and eventually stop working.  It gets a bit worse because space is such a hostile environment.  Components on spacecraft need to be rated for the radiation they're exposed to in orbit and radiation degrades some types of parts more and more quickly than others.  



7 comments:

  1. I thought the Hubble was scheduled for replacement this year. I guess I am mot in the loop on current space actions.

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    1. Not exactly.

      They're planning to launch the James Webb Space Telescope in about a month, but that's not really a Hubble replacement. It's infrared only, so no sharp, pretty pictures like Hubble gave. It's both bigger and more exotic technology, though, including being deployed into a sun/earth Lagrange point.

      It will essentially be in solar orbit almost a million miles farther from the sun than we are.

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  2. 31 years isn't a bad life for a converted spy satellite. Though I do hope she's recoverable, and NASA has had a pretty decent record on its un-manned hardware (the Voyagers come to mind,) the orbit she's in isn't exactly the safest.

    Now, fixed up and pushed out farther like the Webb? That might be a good thing. But, well, it's time. She's lasted longer than she was supposed to, and nobody else, Russian, ChiCom, ESA, nobody has launched anything better than her, which says a lot.

    Would be nice if that was one of the potential missions of Starship or a dedicated Crew Dragon flight, to actually look and see what's wrong.

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    1. I think a dedicated Starship mission would work well in a few years. Not sure about how well it could land with that weight, but I'd imagine it has to be in the design requirements if they're planning on transporting lots of cargo to Mars.

      It would be cool to put it in the Smithsonian.

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  3. Didn't the Shuttle fly a repair team to Hubble, maybe more than once? I'm wondering if it has any replacement electronics onboard, with Euro spec soldering assemblies? Those 'green" idiots removed lead from solder, which seems to have enabled whiskers to grow and cause shorts.

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    1. Hi-rel electronics like space, aviation, medical, and military aren't required to be lead-free. They were specifically exempted from the laws when laws started. It's just that all the jelly bean parts (passive components in general) are manufactured Pb-free because why would a company invest in two production lines when they'll sell a relative handful of parts off the low volume, tin-lead line. Too much upkeep, keeping parts separate, all sorts of hassles.

      The amount of lead-containing solder required to keep tin whiskers from forming has been studied and if a company building hi-rel electronics follows that, they can solder Pb-free parts with no problems. They effectively coat those parts with tin-lead solder while manufacturing.

      Meanwhile, the biggest use of lead is in batteries. Something like 2% of the lead used in the world is in electronics soldering so let's go after that! Real bright, right there.

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    2. They also seem to have eliminated lead wheel weights, and now make them from STEEL. lovely, now we get to chase rust on our mag wheels.

      I'm reminded of the annoying result of lending my plumbing torch to my neighbor. I included a variety of solder, since I wasn't clear on exactly what he was trying to do. Got it back a couple days later, and the full roll of leaded solder was missing. Borrower took it on himself to throw it away, telling me that that stuff was dangerous, and I shouldn't have it. That sort of attitude seems to be common with Chinese, from my experience. Not sure why, maybe cultural?

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