Man, what a month. If you’ve been following space news lately, you’ll know what I’m talking about. Jeez, even if you’ve just been following the regular news, you’ve probably heard some of it — the Soyuz MS-10 launch failure was a pretty widely-spread story. (By the way, Roscosmos, the Russian space agency, released a frankly terrifying video from the engineering camera and a statement on what caused the failure — a bent pin in a separation sensor in the strap-on boosters, it looks like.) But there’s been some even more disturbing developments coming in from the world of space telescopes — and I think we might be coming up on the end of an era.
Hubble
Last month, on October 5th, a gyroscope in NASA’s Hubble Space Telescope — used to stabilize the telescope as it takes photos — failed. This wasn’t unexpected, though. NASA said the gyro was exhibiting end-of-life behavior for about a year, and NASA expects the gyros to fail at some point — that’s why Hubble was built with 6 gyros, but only needs 3. It’s also why NASA replaces the gyros in every Space Shuttle Service Mission, but the last (and final, since the Space Shuttle has been retired) service mission was in 2009, almost a decade ago. Over the past 10 years, 2 of the gyros failed and were replaced by backups.
The problem started when the 3rd backup gyro was brought online, and started sending back bad data. NASA determined that the gyro could accurately track position, but was sending back values that were too high, like if your speedometer could tell when you were accelerating or decelerating, but always displayed values 200 km/h too high. In the high precision mode — used when Hubble is taking photos — this was overflowing the sensor, and it could’t be used. While NASA resolved this, Hubble was put into “safe mode.” NASA engineers were able to resolve this gyroscope issue essentially by turning it on and off again, while shaking it. The engineers spun up and spun down the gyro’s while turning the spacecraft around in different directions. This reduced the error, so engineers did it some more. This cleared the issue and Hubble was back to science operation by October 26th
Chandra
Meanwhile, while Hubble was misbehaving, the Chandra X-ray Observatory decided it to wanted some time off, and automatically put itself into safe mode on October 10th after one it’s gyroscopes gave 3-seconds of bad data, causing the on-board computer to calculate an incorrect value for the spacecraft momentum. NASA engineers were able to resolve this by switching to a backup gyroscope, and placing the gyroscope that experienced the glitch in reserve. The telescope returned to “active duty” by October 21st.
Kepler
The saddest development of last month came from the Kepler Space Telescope. After nine years and more than 2,500 exoplanet discoveries, NASA is retiring the spacecraft and ending the mission. Kepler spent almost a decade surveying the sky for planets outside of our solar system, but eventually had to be retired after running out of maneuvering fuel. Before finally ending the mission, NASA scientists continued to operate the satellite, successfully completing multiple observation campaigns and downloading valuable science data even after initial warnings of low fuel.
A Telescope-less Tomorrow?
All these failures point, I think, to a sad reality. The telescopes we’ve all come to know and love are all going to be coming to an end soon. I’ve grown up hearing about discoveries from Kepler, and marveling over Hubble’s magnificent images. Some of the most famous images from outer space — the Butterfly Nebula, the Pillars of Creation, and the Ultra Deep Field Image — came from Hubble. So you can see why I might be saddened by the thought of loosing these satellites.
However, these satellites won’t be the only things to go. Many of our great achievements in space, not only Hubble, but most of the greatest scientific expeditions of our species, will soon start to fail. It’ll mark the end of an era — the end, I think, of the last great era of space, the era of the Space Station, the Space Shuttle, the Galileo mission to Jupiter, the Sojourner, Opportunity, and Spirit rovers on Mars, the Cassini mission to Saturn, and many more. The list goes on. As the hardware for these missions wears out, more and more of our favorite missions will come to a close.
This won’t be the end of exploration – the Transiting Exoplanet Survey Satellite will pick up right where Kepler left off, as will the James Web Space Telescope with Hubble. But with no space agency with a clear plan for what to do next, the era of boundless exploration may soon be over.
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