Darmstadt, we have a problem – ESA reveals its INTEGRAL space telescope was three hours from likely death

Gamma ray-spotting 'scope was spinning uncontrollably and unable to make 'leccy until dramatic rescue


The European Space Agency (ESA) revealed on Monday that its 19-year-old International Gamma-Ray Astrophysics Laboratory (INTEGRAL) had a near-death experience last month when failure of a small yet significant part caused it to spin uncontrollably and prevented its solar panels from generating power.

According to ESA's blog, one of the scope's three active 'reaction wheels' – flywheels that help to stabilise attitude – turned off without warning. Absent the reaction wheel's energy, INTEGRAL rotated dangerously.

The ESA activated Emergency Safe Attitude Mode, but that was ineffective because a July 2020 failure had left the geriatric satellite's thrusters inoperable.

ESA boffins were therefore presented with the challenge of sorting things out despite a patchy data connection from the satellite to ground control, and batteries with just three hours of charge remaining.

The team was able to reactivate the malfunctioning wheel, but the spacecraft just kept wobbling about its axis. The groundside crew deftly turned off non-critical components to buy more time and sent commands to the reaction wheels they hoped would stop the spin.

The team eventually regained control.

Then they lost control, again. The team speculates the second loss was due to the Earth blocking INTEGRAL’s view of the stars that it uses to orient itself. Thankfully, a repeat of the corrective actions repaired the spin again.

To make matters more fascinating, the rescue happened while most of the control team were working from home – thereby presenting the best argument for ongoing remote work, for every job, forever.

Erik Kuulkers, ESA's project scientist for INTEGRAL said the satellite has returned to studying "unexpected explosive events in the Universe".

ESA boffins have fingered a random charged particle hitting INTEGRAL's electricals and sparking a changed state as the possible cause of the malfunction.

"It looks like that the anomaly was triggered by charged particles trapped in the radiation belts around Earth," said Juha-Pekka Luntama, ESA's Head of Space Weather.

Integral's highly elliptical orbit puts its perigee smack dab in the middle of the Van Allen radiation belt and its charged particles held in place by Earth's magnetic field.

The continual belting INTEGRAL takes from such particles, over the years, caused degradation of the telescope's solar arrays.

Keeping a satellite going for two decades is quite a feat. In June of 2020, missions operations manager Richard Southworth detailed a laundry list of challenges the team faces keeping the spacecraft functioning to The Register, including degrading power output and many one-off failures over the years.

But for a spacecraft that has lasted decades beyond its original five-year mission, it's doing very well indeed – living long, and even prospering. ®

Similar topics


Other stories you might like

  • Prisons transcribe private phone calls with inmates using speech-to-text AI

    Plus: A drug designed by machine learning algorithms to treat liver disease reaches human clinical trials and more

    In brief Prisons around the US are installing AI speech-to-text models to automatically transcribe conversations with inmates during their phone calls.

    A series of contracts and emails from eight different states revealed how Verus, an AI application developed by LEO Technologies and based on a speech-to-text system offered by Amazon, was used to eavesdrop on prisoners’ phone calls.

    In a sales pitch, LEO’s CEO James Sexton told officials working for a jail in Cook County, Illinois, that one of its customers in Calhoun County, Alabama, uses the software to protect prisons from getting sued, according to an investigation by the Thomson Reuters Foundation.

    Continue reading
  • Battlefield 2042: Please don't be the death knell of the franchise, please don't be the death knell of the franchise

    Another terrible launch, but DICE is already working on improvements

    The RPG Greetings, traveller, and welcome back to The Register Plays Games, our monthly gaming column. Since the last edition on New World, we hit level cap and the "endgame". Around this time, item duping exploits became rife and every attempt Amazon Games made to fix it just broke something else. The post-level 60 "watermark" system for gear drops is also infuriating and tedious, but not something we were able to address in the column. So bear these things in mind if you were ever tempted. On that note, it's time to look at another newly released shit show – Battlefield 2042.

    I wanted to love Battlefield 2042, I really did. After the bum note of the first-person shooter (FPS) franchise's return to Second World War theatres with Battlefield V (2018), I stupidly assumed the next entry from EA-owned Swedish developer DICE would be a return to form. I was wrong.

    The multiplayer military FPS market is dominated by two forces: Activision's Call of Duty (COD) series and EA's Battlefield. Fans of each franchise are loyal to the point of zealotry with little crossover between player bases. Here's where I stand: COD jumped the shark with Modern Warfare 2 in 2009. It's flip-flopped from WW2 to present-day combat and back again, tried sci-fi, and even the Battle Royale trend with the free-to-play Call of Duty: Warzone (2020), which has been thoroughly ruined by hackers and developer inaction.

    Continue reading
  • American diplomats' iPhones reportedly compromised by NSO Group intrusion software

    Reuters claims nine State Department employees outside the US had their devices hacked

    The Apple iPhones of at least nine US State Department officials were compromised by an unidentified entity using NSO Group's Pegasus spyware, according to a report published Friday by Reuters.

    NSO Group in an email to The Register said it has blocked an unnamed customers' access to its system upon receiving an inquiry about the incident but has yet to confirm whether its software was involved.

    "Once the inquiry was received, and before any investigation under our compliance policy, we have decided to immediately terminate relevant customers’ access to the system, due to the severity of the allegations," an NSO spokesperson told The Register in an email. "To this point, we haven’t received any information nor the phone numbers, nor any indication that NSO’s tools were used in this case."

    Continue reading

Biting the hand that feeds IT © 1998–2021