Psyche asteroid probe experiences an unexplained engine problem
Psyche’s flight path to the asteroid Psyche.
Click for original image.
The probe Psyche, presently on its way to the asteroid of the same name, has experienced a thruster issue with its electric ion-type main engine that has forced engineers to postpone further engine use as they troubleshoot the problem.
Psyche began firing its thrusters in May 2024. On April 1, the spacecraft detected a pressure drop in the line that feeds the xenon gas to the thrusters, going from 36 pounds per square inch (psi) to about 26 psi. As designed, the orbiter powered off the thrusters in response to the decrease.
The mission team has chosen to defer thrusting while engineers work to understand the pressure decrease. The mission design supports a pause in thrusting until at least mid-June before the spacecraft would see an effect on its trajectory. The electric propulsion system has two identical fuel lines, and the team may decide to switch to the backup fuel line to resume thrusting.
This mission has been plagued with problems. First its software was completed late, forcing a year delay in its launch. Next it was discovered — too late to fix — that transistors on the spacecraft had not been properly hardened for the hostile environment of space. Engineers hope these transistors “will heal themselves” once in that environment, but there are no guarantees. [My memory is becoming fuzzy. As many of my readers pointed out, this transistor problem was with Europa Clipper, not Psyche.]
Now its electric ion engine, essential to getting it to Psyche, is not working properly.
If this problem is fixed and Pysche resumes engine firing, it is targeting an arrival at the asteroid Psyche in 2029.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Psyche’s flight path to the asteroid Psyche.
Click for original image.
The probe Psyche, presently on its way to the asteroid of the same name, has experienced a thruster issue with its electric ion-type main engine that has forced engineers to postpone further engine use as they troubleshoot the problem.
Psyche began firing its thrusters in May 2024. On April 1, the spacecraft detected a pressure drop in the line that feeds the xenon gas to the thrusters, going from 36 pounds per square inch (psi) to about 26 psi. As designed, the orbiter powered off the thrusters in response to the decrease.
The mission team has chosen to defer thrusting while engineers work to understand the pressure decrease. The mission design supports a pause in thrusting until at least mid-June before the spacecraft would see an effect on its trajectory. The electric propulsion system has two identical fuel lines, and the team may decide to switch to the backup fuel line to resume thrusting.
This mission has been plagued with problems. First its software was completed late, forcing a year delay in its launch. Next it was discovered — too late to fix — that transistors on the spacecraft had not been properly hardened for the hostile environment of space. Engineers hope these transistors “will heal themselves” once in that environment, but there are no guarantees. [My memory is becoming fuzzy. As many of my readers pointed out, this transistor problem was with Europa Clipper, not Psyche.]
Now its electric ion engine, essential to getting it to Psyche, is not working properly.
If this problem is fixed and Pysche resumes engine firing, it is targeting an arrival at the asteroid Psyche in 2029.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Big probes with lots of redundancies and thrust — we need Starship in mass production ASAP.
I’m wondering if the xenon propellant could get ‘slushy’ in the lines or tank? It’s listed as having a melting temp (earth pressure) of -112 C.
I don’t recall any previous problems with the ‘Dawn’ and ‘Deep Space 1’ spacecraft which both used xenon ion drives. I believe Deep Space 1 had a hydrazine attitude thruster failure at some point and a limited star tracker system before eventually being shut down.
” Next it was discovered — too late to fix — that transistors on the spacecraft had not been properly hardened for the hostile environment of space. Engineers hope these transistors “will heal themselves” once in that environment, but there are no guarantees.”
Wasn’t that Europa Clipper ?
Yes, it was.
Dick and Richard: My memory is getting fuzzy, which is why I should always check. I’ve corrected the error. Thank you.
Psyche has definitely had its issues, but I hate to beat up on it for something a different JPL team (and contractor) screwed up!
I recall Dwayne Day talking about the AIAA SciTech presentation by the Psyche team a few months back, which noted that the electric propulsion system was actually operating significantly better than projected — like about 5% better. So this development came as a surprise.
Hopefully it’s one of those little glitches that turns out being less than meets the eye. The system does have a redundant line, but obviously they’d hate to have to switch over to it so early in the mission if they do not have to.