NASA intends to launch the CAPSTONE cubesat mission in early June. This 12U satellite will test the orbital mechanics of the Near Rectilinear Halo Orbit (NRHO) to be used by the Artemis Gateway station, as well as future lunar lander missions. This orbit utilizes the gravity of both Earth and Moon to achieve stability, as well as low velocity cost of entry and exit, and periodic access to the lunar surface.
It also lays the groundwork for cislunar positioning & navigation via a peer-to-peer network of spacecraft that share their estimates of position and velocity, which are then conbined to reduce the estimation error. This is needed due to the difficulty of creating a lunar GPS system, similar to Earth.
https://www.nasa.gov/directorates/space ... t/capstone
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- Francoflier
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Re: NASA Capstone Mission
To be launched soon on a Rocket Lab Electron rocket (not) near you!
Those Halo orbits are really fascinating. It will be great to see how feasible and practical they are in real life use.
Those Halo orbits are really fascinating. It will be great to see how feasible and practical they are in real life use.
Re: NASA Capstone Mission
NASA has announced a launch delay for CAPSTONE while software is updated at the launch facility in New Zealand. No new date given pending software checkout. The window extends to June 22.
Re: NASA Capstone Mission
The launch date for CAPSTONE is now no earlier than June 25th. The mission is undergoing a software update and testing.
Re: NASA Capstone Mission
CAPSTONE launch now shifted to June 27th. The launch window runs to July 27th and the arrival date (November 13th) is insensitive to the launch date.
Re: NASA Capstone Mission
CAPSTONE mission launch now shifted one day to June 28th.
Re: NASA Capstone Mission
CAPSTONE mission launch was successful and nominal. Now in a highly elliptical orbit. Over the next few days, the Photon stage will periodically fire until the orbital height and speed are suitable for TLI. Then the spacecraft will be on a low energy transfer, arriving at the NRHO on November 13th.
Re: NASA Capstone Mission
Congrats to Rocketlab for their first deep space mission launch.
Re: NASA Capstone Mission
GDB wrote:Congrats to Rocketlab for their first deep space mission launch.
Especially since they had to tweak the Electron stages significantly to get to the required orbit. That made it a very low-margin mission. It's quite a feat for such a small rocket. They were concerned even about the weight of the ice outside the cryo stages.
Re: NASA Capstone Mission
CAPSTONE mission has completed the final orbital burn of the HyperCurie engine, to insert the payload into ballistic lunar trajectory. CAPSTONE has separated from the Photon vehicle and is on its way to NRHO around the moon.
Kudos to RocketLab, this has been a great mission for them and paves the way for future extra-orbital missions for the Electron launch platform.
Kudos to RocketLab, this has been a great mission for them and paves the way for future extra-orbital missions for the Electron launch platform.
Re: NASA Capstone Mission
Update on CAPSTONE, the NASA controllers lost communication with the spacecraft shortly after separation from the Photon stage, and are trying to reestablish contact. They have several days to work out this problem before a correction burn is required to adjust the trajectory. Hoping they are able to do so.
Re: NASA Capstone Mission
Good news on CAPSTONE, communications are restored and spacecraft is healthy. Mission is continuing on schedule.
Re: NASA Capstone Mission
The deferred maneuvering burn is now scheduled for tomorrow morning. The glitch ocurred during commissioning of the communications subsystem, and the root cause is under investigation. The spacecraft continued to operate autonomously without comms, as it was programmed to do.
https://blogs.nasa.gov/artemis/2022/07/ ... -maneuver/
https://blogs.nasa.gov/artemis/2022/07/ ... -maneuver/
Re: NASA Capstone Mission
Lots of pucker factor with lost comms. Wouldn’t want to be the engineer responsible for that.
Re: NASA Capstone Mission
Manuevering burn today was good, CAPSTONE on course for NRHO insertion.
Root cause for communications issue was found to be an improperly formatted diagnostic command, which shut down the radio, combined with a logic error in the flight software that failed to reset it. However there is other watchdog code that resets the radio after a long period of no communication from Earth.
https://blogs.nasa.gov/artemis/2022/07/ ... -capstone/
Root cause for communications issue was found to be an improperly formatted diagnostic command, which shut down the radio, combined with a logic error in the flight software that failed to reset it. However there is other watchdog code that resets the radio after a long period of no communication from Earth.
https://blogs.nasa.gov/artemis/2022/07/ ... -capstone/
Re: NASA Capstone Mission
The NASA CAPSTONE mission went into safe mode at the end of the TCM 3 manuever, one of several which insert it into the desired lunar NRHO orbit. Teams are in communication with the satellite and are investigating the source of the issue.
https://advancedspace.com/news/
https://youtu.be/FFkKaBxQ214
https://advancedspace.com/news/
https://youtu.be/FFkKaBxQ214
Re: NASA Capstone Mission
Avatar2go wrote:The NASA CAPSTONE mission went into safe mode at the end of the TCM 3 manuever, one of several which insert it into the desired lunar NRHO orbit. Teams are in communication with the satellite and are investigating the source of the issue.
https://advancedspace.com/news/
https://youtu.be/FFkKaBxQ214
Scott Manley mentioned in his latest update how enhanced recent solar activity has affected a satellite in geostationary orbit, could it have done to same to Capstone?
Re: NASA Capstone Mission
GDB wrote:
Scott Manley mentioned in his latest update how enhanced recent solar activity has affected a satellite in geostationary orbit, could it have done to same to Capstone?
It's possible. All we know for sure is that something happened right at the end of the manuever. Since then they have had intermittent periods of downlink on the 70 meter dish. Last one was a few minutes ago. Doesn't help that CAPSTONE is at it's farthest distance from earth right now.
Re: NASA Capstone Mission
CAPSTONE now has a sustained downlink carrier on the uplink dish, which is a sign that communications have stabilized.
Re: NASA Capstone Mission
The NASA CAPSTONE spacecraft has been identified to be in a slow tumble. An unknown event at the end of the TCM-3 burn saturated the reaction control wheels, causing the vehicle to lose orientation.
Teams have stabilized the vehicle enough to make it power-positive, and to increase the communication intervals. They have a detumble plan prepared, that they practiced after separation. Has to be done slowly at first, but as power margins improve, they should be able to regain control of orientation.
It's on course and they have some time before the next TCM burn. So will be working on identifying the cause.
They thanked the NASA Deep Space Network. Without their 70 meter dishes, at that distance they could not communicate with the spacecraft. It's a cubesat with small antennas and low transmit power.
https://advancedspace.com/capstone-12sep22-update/
Teams have stabilized the vehicle enough to make it power-positive, and to increase the communication intervals. They have a detumble plan prepared, that they practiced after separation. Has to be done slowly at first, but as power margins improve, they should be able to regain control of orientation.
It's on course and they have some time before the next TCM burn. So will be working on identifying the cause.
They thanked the NASA Deep Space Network. Without their 70 meter dishes, at that distance they could not communicate with the spacecraft. It's a cubesat with small antennas and low transmit power.
https://advancedspace.com/capstone-12sep22-update/
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- Francoflier
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Re: NASA Capstone Mission
That's puzzling.
What do these cubesats use for station keeping?
Do they have electric thusters or chemical ones?
Hopefully they are able to recover it and proceed with the mission normally.
What do these cubesats use for station keeping?
Do they have electric thusters or chemical ones?
Hopefully they are able to recover it and proceed with the mission normally.
Re: NASA Capstone Mission
Francoflier wrote:That's puzzling.
What do these cubesats use for station keeping?
Do they have electric thusters or chemical ones?
Hopefully they are able to recover it and proceed with the mission normally.
The CAPSTONE cubesat has chemical thrusters but very little propellant. The entire thing weighs 55 pounds. I think around 12 pounds are propellant. It needs most of that for planned trajectory correction burns.
The reason it's on the efficient ballistic trajectory, is that it has so little ability to thrust. The idea is that the NRHO is also extremely efficient orbit. The cubesat relies on reaction wheels to orient itself, instead of thrust.
They mentioned that thrust was an option if they invade their margins, but they have to warm up the propellant to do that, which eats into their power budget. So my guess is they try to dampen out the tumble with the wheels first, than maybe fall back on the thrusters as a last resort.
I too hope the detumble plan works. This is an extremely ambitious mission, for the size, weight and cost of the vehicle. Despite the problems, it's impressive that they have recovery capabilities.
Re: NASA Capstone Mission
Avatar2go wrote:They mentioned that thrust was an option if they invade their margins, but they have to warm up the propellant to do that, which eats into their power budget. So my guess is they try to dampen out the tumble with the wheels first, than maybe fall back on the thrusters as a last resort.
Detumbling with wheels doesn't work. Reaction wheels transfer momentum within the spacecraft but the overall angular momentum remains constant. You can, of course, try to reduce or stop the spacecraft rotation with wheels but then you'll bring the wheels closer to saturation. Desaturating the wheels requires momentum dumping via external torques, in this case thrusters. So the anomaly is going to eat into their fuel reserves either way.
The good thing is, external disturbing torques on the chosen orbit are tiny compared to typical LEO satellites. The wheels should take a long time to saturate (in regular operations), so that the fuel amount required for attitude maintenance is small.
I suspect that one of the thrusters malfunctioned, providing either more or less thrust than expected. They need to properly identify and fix that issue first before returning to normal operations, or else there's considerable risk it might happen again.
Re: NASA Capstone Mission
mxaxai wrote:Avatar2go wrote:They mentioned that thrust was an option if they invade their margins, but they have to warm up the propellant to do that, which eats into their power budget. So my guess is they try to dampen out the tumble with the wheels first, than maybe fall back on the thrusters as a last resort.
Detumbling with wheels doesn't work. Reaction wheels transfer momentum within the spacecraft but the overall angular momentum remains constant. You can, of course, try to reduce or stop the spacecraft rotation with wheels but then you'll bring the wheels closer to saturation. Desaturating the wheels requires momentum dumping via external torques, in this case thrusters. So the anomaly is going to eat into their fuel reserves either way.
The good thing is, external disturbing torques on the chosen orbit are tiny compared to typical LEO satellites. The wheels should take a long time to saturate (in regular operations), so that the fuel amount required for attitude maintenance is small.
I suspect that one of the thrusters malfunctioned, providing either more or less thrust than expected. They need to properly identify and fix that issue first before returning to normal operations, or else there's considerable risk it might happen again.
Ok, thanks, that makes sense that the vehicle is still saturated with angular momentum. They said they had stablized it somewhat, but didn't say how. I assumed that meant the wheels.
Probably the first goal is to attain normal orientation first for battery charge and then for communication. I'm sure their detumble plan will allow for the possibility that not every thruster is working properly.
Then I agree they can't attempt another TCM until the understand the problem. But fortunately they have some time before one is needed.
Re: NASA Capstone Mission
An update on CAPSTONE: the spacecraft has been additionally stabilized, especially with regard to communication, but teams are still working to warm up the propellant enough to enable the detumble plan. It's challenging due to limited power budget while the spacecraft is tumbling, but the power margin is sufficiently positive. It just takes time to due to the rate limit.
They continue to investigate the cause of the event that initiated the tumble.
https://advancedspace.com/capstone-15sep22-update/
They continue to investigate the cause of the event that initiated the tumble.
https://advancedspace.com/capstone-15sep22-update/
Re: NASA Capstone Mission
NASA CAPSTONE Update: The propellant has been warmed over the last week, and teams are preparing to execute the detumble program. Communications remain good.
https://advancedspace.com/capstone-21se ... #more-1600
https://advancedspace.com/capstone-21se ... #more-1600
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- Francoflier
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Re: NASA Capstone Mission
Thanks for the update.
I wonder if there's a risk that a possible thruster failure could have caused the tumble in the first and could therefore cause more trouble during the de-tumbling burn.
Or are those different thrusters?
I wonder if there's a risk that a possible thruster failure could have caused the tumble in the first and could therefore cause more trouble during the de-tumbling burn.
Or are those different thrusters?
Re: NASA Capstone Mission
Francoflier wrote:Thanks for the update.
I wonder if there's a risk that a possible thruster failure could have caused the tumble in the first and could therefore cause more trouble during the de-tumbling burn.
Or are those different thrusters?
I think that's a definite risk. They have not mentioned the root cause of the anomaly, perhaps they don't know yet. My guess is that in their detumble plan, there will be individual test firings of each thruster, before they rely on them for the detumble.
The next question after that, is if the mission will be shorter because of the propellant consumed. But one thing at a time, first they have to regain complete control.
Re: NASA Capstone Mission
CAPSTONE is the little mission that could!
Advanced Space has determined that a thruster propellant valve stuck partially open, which caused the spacecraft to tumble during the last trajectory correction manuever. They were then able to execute their detumble plan this morning, which was successful.
The spacecraft has now resumed 3-axis attitude control with the reaction wheels, with solar panels aligned with the sun and antenna aligned with earth. They are working out how to compensate for the stuck valve at the next correction manuever.
https://advancedspace.com/capstone-miss ... ss-update/
Advanced Space has determined that a thruster propellant valve stuck partially open, which caused the spacecraft to tumble during the last trajectory correction manuever. They were then able to execute their detumble plan this morning, which was successful.
The spacecraft has now resumed 3-axis attitude control with the reaction wheels, with solar panels aligned with the sun and antenna aligned with earth. They are working out how to compensate for the stuck valve at the next correction manuever.
https://advancedspace.com/capstone-miss ... ss-update/
Re: NASA Capstone Mission
Impressive work! Hopefully they won't need that particular thruster.
Re: NASA Capstone Mission
The NASA CAPSTONE Mission does it's Near Rectilinear Halo Orbit (NRHO) lunar insertion burns tomorrow. Since it doesn't have much thrust, it relies on tweaking a lunar encounter with gravity assist.
If it misses, it will fly off into space with no chance of recovery. If it succeeds, it will be in lunar orbit the same time as Orion, later this month.
https://fxtwitter.com/advancedspace/sta ... 6595954690
If it misses, it will fly off into space with no chance of recovery. If it succeeds, it will be in lunar orbit the same time as Orion, later this month.
https://fxtwitter.com/advancedspace/sta ... 6595954690
Re: NASA Capstone Mission
Here is a direct link to the NASA information:
https://www.nasa.gov/feature/ames/capst ... o-the-moon
https://www.nasa.gov/feature/ames/capst ... o-the-moon
Re: NASA Capstone Mission
Avatar2go wrote:Here is a direct link to the NASA information:
https://www.nasa.gov/feature/ames/capst ... o-the-moon
Great stuf,f thanks for the updates.
Re: NASA Capstone Mission
In the Artemis media briefing, Jim Free confirmed the first CAPSTONE NRHO insertion burn was successful. Further corrections over the next few days.
Re: NASA Capstone Mission
Rocketlab proudly announce;
https://www.youtube.com/watch?v=w4XWnZNvazY
https://www.youtube.com/watch?v=w4XWnZNvazY
Re: NASA Capstone Mission
Further corrections remain to the CAPSTONE orbit. Rocket Labs taking a victory lap for their own role.
Re: NASA Capstone Mission
CAPSTONE is now in NRHO, having successfully completed the final burn sequence.
http://www.nasa.gov/press-release/capst ... n-missions
http://www.nasa.gov/press-release/capst ... n-missions
Re: NASA Capstone Mission
Avatar2go wrote:CAPSTONE is now in NRHO, having successfully completed the final burn sequence.
http://www.nasa.gov/press-release/capst ... n-missions
Glad it made it after all the tribulations.
Re: NASA Capstone Mission
A mission update from CAPSTONE: it has recovered from a temporary glitch that prevented reception of commands, by rebooting via a watchdog timer.
It has completed 12 NRHO orbits and found that fewer corrections are needed than anticipated, on average once every 2 orbits (2 weeks). It's also completed assessments of lunar eclipses which challenge power and thermal management requirements.
It has attempted it's first positional navigational exercise with the Lunar Reconnaissance Orbiter (LRO), with partial success. It will make several more attempts, plus begin utilizing the on-board atomic clock to increase precision. Despite earlier thruster issues, it has 56% propellant remaining and should have a long life on orbit.
https://advancedspace.com/capstone-miss ... y-at-moon/
Another lunar cubesat, Lunar Flashlight, which was to use "green" propellants, has had thruster issues and is down to one partial thruster. It won't be able to enter NRHO, but instead will try to use very high elliptical Earth orbit to do lunar flybys.
https://www.space.com/nasa-moon-probe-l ... impossible
It has completed 12 NRHO orbits and found that fewer corrections are needed than anticipated, on average once every 2 orbits (2 weeks). It's also completed assessments of lunar eclipses which challenge power and thermal management requirements.
It has attempted it's first positional navigational exercise with the Lunar Reconnaissance Orbiter (LRO), with partial success. It will make several more attempts, plus begin utilizing the on-board atomic clock to increase precision. Despite earlier thruster issues, it has 56% propellant remaining and should have a long life on orbit.
https://advancedspace.com/capstone-miss ... y-at-moon/
Another lunar cubesat, Lunar Flashlight, which was to use "green" propellants, has had thruster issues and is down to one partial thruster. It won't be able to enter NRHO, but instead will try to use very high elliptical Earth orbit to do lunar flybys.
https://www.space.com/nasa-moon-probe-l ... impossible
Re: NASA Capstone Mission
Another CAPSTONE update. The 6-month mission has been extended another 12 months, as it has plenty of propellant remaining.
It has established the stability of the Near Rectilinear Halo Orbit to be used by Gateway, and is carrying out it's communication, ranging and position-finding task with the Lunar Reconnaissance Orbiter (LRO). This can serve in lieu of GPS in the lunar environment, for navigational purposes. Each vehicle uses information from the other to determine position in space.
I love this mission because it has a tiny budget and spacecraft (microwave oven), yet has carried out significant science. The mission software has been adapted may times to overcome adversity, with lots of learning in the process. It's largely a software defined mission as there is so little room for hardware, but that has been an advantage.
https://advancedspace.com/capstone-17apr23-update/
It has established the stability of the Near Rectilinear Halo Orbit to be used by Gateway, and is carrying out it's communication, ranging and position-finding task with the Lunar Reconnaissance Orbiter (LRO). This can serve in lieu of GPS in the lunar environment, for navigational purposes. Each vehicle uses information from the other to determine position in space.
I love this mission because it has a tiny budget and spacecraft (microwave oven), yet has carried out significant science. The mission software has been adapted may times to overcome adversity, with lots of learning in the process. It's largely a software defined mission as there is so little room for hardware, but that has been an advantage.
https://advancedspace.com/capstone-17apr23-update/
Re: NASA Capstone Mission
An update from NASA/JPL on the Lunar Flashlight cubesat mission, launched in December.
The propulsion package utilized a "green" monopropellant, instead of hydrazine which is highly toxic. It appears that debris from 3D printing, may have partially obstructed the propellent lines.
The team was able to increase thrust by pressurizing the propellant above safe levels, and focusing on just one thruster, but it wasn't enough improvement to salvage the mission.
Thus the team cannot get enough propellant flow to the thruster, to sufficiently alter the vehicle orbit or trajectory, before the window closes for a useful orbit. So it will return from it's flyby of the Moon, do a close flyby of the Earth, and then head out to space in a heliocentric orbit.
The cubesat is otherwise fully functional, including the instrument package, so the team will look for other opportunities to test & utilize the systems.
https://www.jpl.nasa.gov/news/nasa-call ... -successes
The propulsion package utilized a "green" monopropellant, instead of hydrazine which is highly toxic. It appears that debris from 3D printing, may have partially obstructed the propellent lines.
The team was able to increase thrust by pressurizing the propellant above safe levels, and focusing on just one thruster, but it wasn't enough improvement to salvage the mission.
Thus the team cannot get enough propellant flow to the thruster, to sufficiently alter the vehicle orbit or trajectory, before the window closes for a useful orbit. So it will return from it's flyby of the Moon, do a close flyby of the Earth, and then head out to space in a heliocentric orbit.
The cubesat is otherwise fully functional, including the instrument package, so the team will look for other opportunities to test & utilize the systems.
https://www.jpl.nasa.gov/news/nasa-call ... -successes
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- ReverseFlow
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Re: NASA Capstone Mission
Avatar2go wrote:An update from NASA/JPL on the Lunar Flashlight cubesat mission, launched in December.
The propulsion package utilized a "green" monopropellant, instead of hydrazine which is highly toxic. It appears that debris from 3D printing, may have partially obstructed the propellent lines.
The team was able to increase thrust by pressurizing the propellant above safe levels, and focusing on just one thruster, but it wasn't enough improvement to salvage the mission.
Thus the team cannot get enough propellant flow to the thruster, to sufficiently alter the vehicle orbit or trajectory, before the window closes for a useful orbit. So it will return from it's flyby of the Moon, do a close flyby of the Earth, and then head out to space in a heliocentric orbit.
The cubesat is otherwise fully functional, including the instrument package, so the team will look for other opportunities to test & utilize the systems.
https://www.jpl.nasa.gov/news/nasa-call ... -successes
You would have thought that they would perform a free flow test through the pipes before installing them.
And cleaning/flushing them beforehand.
Especially if it is a 'new' 3D printed part.
Re: NASA Capstone Mission
ReverseFlow wrote:You would have thought that they would perform a free flow test through the pipes before installing them.
And cleaning/flushing them beforehand.
Especially if it is a 'new' 3D printed part.
Yeah, I think it's best guess speculation, as to the most likely cause. Something has clogged the fuel passageways or the valves. I'm sure they did flush and clean. But maybe particles were dislodged during the launch vibration. Who knows.
They've used that system on another LEO cubesat as a test, before sending this one to the moon, and it worked for that vehicle. I'm sure they weren't expecting this issue.
It's a university project, in keeping with the NASA philosophy of distributing cubesat technology as low cost access to space, hitching a ride on another mission launch. So the failure rate is expected to be around 50%. It's amazing what they pack into such a small volume.
Re: NASA Capstone Mission
Avatar2go wrote:Yeah, I think it's best guess speculation, as to the most likely cause. Something has clogged the fuel passageways or the valves. I'm sure they did flush and clean. But maybe particles were dislodged during the launch vibration. Who knows.
It's also quite difficult (and expensive) to test fire the thruster in an assembled cubesat. So you launch and pray that it still works in orbit. Since thrusters on small satellites are still relatively new, I expect such failures to remain common for some time. Launch, fail, improve and launch again, until it works.
Re: NASA Capstone Mission
The CAPSTONE mission continues to perform beyond expectations, well into it's one-year extended mission. It has now completed all of its mission objectives, after a rocky start with numerous problems at initial release.
It has provided extended orbital data for NRHO, which is being incorporated into the Gateway mission planning. It has also completed all of its positioning experiments, communicating with the LRO lunar orbiter, as well as using the onboard atomic clock with Earth signals to establish position with high accuracy.
It's life will likely be limited by radiation events, which have caused several resets as the sun approaches the solar maximum. But it has plenty of propellant remaining.
Advanced Space is now working on a small-sat named Oracle, which will monitor cislunar space, and provide navigational positioning services within that region.
https://spacenews.com/capstone-working- ... er-launch/
It has provided extended orbital data for NRHO, which is being incorporated into the Gateway mission planning. It has also completed all of its positioning experiments, communicating with the LRO lunar orbiter, as well as using the onboard atomic clock with Earth signals to establish position with high accuracy.
It's life will likely be limited by radiation events, which have caused several resets as the sun approaches the solar maximum. But it has plenty of propellant remaining.
Advanced Space is now working on a small-sat named Oracle, which will monitor cislunar space, and provide navigational positioning services within that region.
https://spacenews.com/capstone-working- ... er-launch/
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