The Repair is In: Hubble’s Troubles Seem Over for Now


Excellent information this morning from low Earth orbit, the place the Hubble Area Telescope is again on-line after an extended and worrisome month of state of no activity following a glitch with the observatory’s payload pc.

We lately lined the Hubble payload pc in some intensity; on the time, NASA used to be nonetheless very a lot within the prognosis segment of the restoration, and had but to decide a root purpose. However the investigation used to be pointing to one of two conceivable culprits: the Command Unit/Science Knowledge Formatter (CU/SDF), the module that interfaces the more than a few science tools, or the Energy Regulate Unit (PCU), which gives regulated energy for the whole lot within the payload pc, extra verbosely referred to as the SI C&DH, or Clinical Software Command and Knowledge Dealing with Unit.

Within the two weeks since that document, NASA made sluggish however secure development, methodically trying out each and every side of the SI C&DH. It wasn’t till simply two days in the past, on July 14, that NASA made a cast choice on root purpose: the Energy Regulate Unit, or extra particularly, the facility provide coverage circuit at the PCU’s 5-volt rail. The circuit is designed to watch the rail for undervoltage or overvoltage prerequisites, and to reserve the SI C&DH to close down if the voltage is out of spec. It’s now not fully transparent whether or not the PCU is in reality hanging out one thing rather than 5 volts, or if the safety circuit has possibly degraded since all of the SI C&DH used to be changed within the ultimate carrier undertaking in 2009. However both approach, the repair is similar: transfer to the backup PCU, a step that used to be moderately deliberate out and done on July fifteenth.

To their credit score, the company took pains that everybody concerned could be loose from any sense of drive to hurry a repair — the 30-year-old spacecraft used to be solid, its tools had been all safely close down, and so the crucial used to be to mend the issue with out inflicting any collateral injury, or taking a step that couldn’t be undone. And extra kudos pass to NASA for transparency — the internet web page detailing their efforts to save lots of Hubble reads virtually like a construct go online one of our initiatives.

There’s nonetheless reasonably just a little of labor to be carried out to get Hubble again into trade — the science tools must be woken up and looked at, as an example — but when all is going smartly, we must see science knowledge get started flowing again from the gap telescope quickly. It’s a aid that NASA used to be ready to tug this repair off, however the truth that Hubble is all the way down to its ultimate backup is a reminder Hubble’s days are numbered, and that one of the simplest ways to honor the feats of engineering derring-do that stored Hubble this time and lots of occasions prior to is to stay doing nice science for so long as conceivable.