Due to thruster problem, the Mercury orbiter BepiColombo will arrive at Mercury almost one year late
The joint ESA and JAXA Mercury mission BepiColombo will now reach its destination eleven months late because its ion electric thrusters are producing less thrust than expected.
The spacecraft is actually made up of two orbiters, one built by the European Space Agency (ESA) and the second built by Japan’s space agency JAXA. During launch and the journey to Mercury each is attached to a third spacecraft called the Mercury Transfer Module (MTM), which has the large electric ion thrusters used for making the mid-course corrections prior to and after each fly-by of the Earth (once), Venus (twice), and Mercury (six) before finally entering orbit around Mercury. It has already completed the Earth, Venus and three Mercury fly-bys.
In April 2024 engineers discovered that during a mid-course correction on April 26st the MTM’s thrusters failed to produce the desired thrust.
Engineers identified unexpected electric currents between MTM’s solar array and the unit responsible for extracting power and distributing it to the rest of the spacecraft. Onboard data imply that this is resulting in less power available for electric propulsion. ESA’s BepiColombo Mission Manager, Santa Martinez explains: “Following months of investigations, we have concluded that MTM’s electric thrusters will remain operating below the minimum thrust required for an insertion into orbit around Mercury in December 2025.”
In order not to lose the mission entirely, the science team has come up with a new trajectory that will have it fly past Mercury on its fourth fly-by on September 4, 2024 only 103 miles above the surface, 22 miles closer than originally planned. This will give it a larger slingshot speed boost to help make up for the under-powered thrusters. It will then make its planned fifth and sixth Mercury fly-bys in December ’24 and January ’25, the adjusted route having it arrive in Mercury orbit eleven months later than planned, in November 2026.
This new plan however means that the pictures taken this week during the Mercury fly-by will provide some nice high resolution details, far better than those produced by the earlier fly-bys.
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
The joint ESA and JAXA Mercury mission BepiColombo will now reach its destination eleven months late because its ion electric thrusters are producing less thrust than expected.
The spacecraft is actually made up of two orbiters, one built by the European Space Agency (ESA) and the second built by Japan’s space agency JAXA. During launch and the journey to Mercury each is attached to a third spacecraft called the Mercury Transfer Module (MTM), which has the large electric ion thrusters used for making the mid-course corrections prior to and after each fly-by of the Earth (once), Venus (twice), and Mercury (six) before finally entering orbit around Mercury. It has already completed the Earth, Venus and three Mercury fly-bys.
In April 2024 engineers discovered that during a mid-course correction on April 26st the MTM’s thrusters failed to produce the desired thrust.
Engineers identified unexpected electric currents between MTM’s solar array and the unit responsible for extracting power and distributing it to the rest of the spacecraft. Onboard data imply that this is resulting in less power available for electric propulsion. ESA’s BepiColombo Mission Manager, Santa Martinez explains: “Following months of investigations, we have concluded that MTM’s electric thrusters will remain operating below the minimum thrust required for an insertion into orbit around Mercury in December 2025.”
In order not to lose the mission entirely, the science team has come up with a new trajectory that will have it fly past Mercury on its fourth fly-by on September 4, 2024 only 103 miles above the surface, 22 miles closer than originally planned. This will give it a larger slingshot speed boost to help make up for the under-powered thrusters. It will then make its planned fifth and sixth Mercury fly-bys in December ’24 and January ’25, the adjusted route having it arrive in Mercury orbit eleven months later than planned, in November 2026.
This new plan however means that the pictures taken this week during the Mercury fly-by will provide some nice high resolution details, far better than those produced by the earlier fly-bys.
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
I like your last note, I could totally see an article touting the better than expected pictures as a win with the details of a delayed primary mission being later ;-).
Thanks so much for the report, and happy Labor day!