IonStorm

Debris is an unknown (and monitoring the rocks would be good science). But there are always risks with spacecraft component failures, some could result in a collision or loss of communication. Space is unforgiving, though OSIRIS-REx has performed impressively well, past performance is no guarantee of future results. The risk is low, but the consequences of total mission failure after success for an optional observation is not acceptable. The risk is heightened by the operations team being so tired and/or are being transferred to other projects. I would personally love to go back and look at the cool stuff, but the decision to stand down makes sense. I'm delighted to share with this community. You all make up a segment of the public with a greater understanding of and interest in spaceflight due to KSP, which is fun.

Cost and risk is the reason, nothing technical. The spacecraft returned to orbit after similar departures after the rehearsals. OSIRIS-REx is a cost capped mission. Every dollar spent in mission operations is a dollar that is not available for sample analysis. NASA strongly encourages fiscal restraint and discipline in avoiding cost growth and "science creep." The cost of the maneuver is not in ∆V, but in labor. It is several weeks of intensive planning to perform the delicate maneuvers to return the spacecraft to orbit. The team to do that work is exhausted. Furthermore, there is non-zero risk of damaging the spacecraft. At this point, any risk to the sample: the prime mission objective, is unacceptable. More lessons KSP doesn't teach.

The spacecraft isn’t much of a gravity tractor. It moved all over, so the forces didn’t add up much. We monitored the position for Yarkovsky measurements and the spacecraft impacts were below the limit of detection. As you indicate, though Bennu is small (7E+10kg) the spacecraft is much smaller (2E+3kg).

Yes. After the “large” 40cm/s burn to leave the TAG site, the spacecraft is still drifting away from Bennu.

It depends on the density you assume. A reasonable number is about 2kg. It would be nice to go back and look at the site. Lots to learn, but that comes at a cost: in both money and risk. With a collected sample, unfortunately it isn’t worth it. Two differences from KSP: no F9 and operating a spacecraft also takes funds.

There are a range of models and there is hope to be able to use some of arm motions to generate an estimate. The top priority was getting the sample safely stored. That done we can try to look at the data and refine the models. Though, since we will know for sure in three years and there is nothing we can do with the result other than improve our sample allocation and curation plans, it isn't clear that devoting a lot of engineering time for analysis is necessary now (though it would be interesting).

The sample is stowed. https://www.asteroidmission.org/?latest-news=osiris-rex-in-the-midst-of-stow Note the specks of Bennu dust from TAG on the white square in the bottom left (an OCAMS Radiator).

The SRC is not a pressure vessel, that would require a lot more mass. However, the vent to atmosphere is through a filter. You can see it in panel b in the figure in my previous post above the ne in witness as a circle in the top of the internal canister. It will be analyzed for trapped volatiles. See section 7.2-7.6 of Dworkin et al. 2018 if you want details of what is trapped at what efficiency in lab testing.

The sample return capsule (SRC) is designed to have a separate compartment for the TAGSAM head from the electronics and parachute. In the below picture (Bierhaus et al. 2018) on the right you can see the capture ring on which the TAGSAM head sits. When the lid closes the compartment with the sample is dust-tight. We anticipated that there would be loose material, particularly during spacecraft operations and re-entry, so this is within the scope of testing. The SRC will land in the Utah Test and Training Range in Dugway, UT at 8:40am MDT on September 24, 2023. Also, I'm actually not an engineer, but a scientist (Ph.D. in biochemistry). There are a few others here. The deputy PI of the Dragonfly mission is active on the forums. I've been playing KSP since v0.10.1 (who remembers the Overthrottle light?), but I don't have a lot to time to play and less time for the forums, except for this thread. As it happens, I gave a short on OSIRIS-REx overview talk today with a colleague at https://www.ustream.tv/recorded/128367108, if you want some additional details on the mission. And yes, you are correct getting Bennu to Mars would take an awful lot of energy. The orbital diagram you show from the day before the OSIRIS-REx launch from the old JPL Small Body Database Browser doesn't even give a sense of the inclination change needed. The new version of the diagram is easier to see.

No. One of mission objectives is get data not to let Bennu land on Earth in 2175-2199 . But, several tonnes from different locations and depths would be illuminating. However, I'll be quite content with a TAGSAM head overflowing with regolith.

Yes. Plus we want all the adhering dust and the material on the contact pads.

No, just being explicit for the lurkers

There are two gas bottles left, but only one sampling head and one sample return capsule. So after the sample is back on Earth one could try creative things to do with the gas, like trying to clean the optics or making a crater with it on some asteroid. Those scenes were never accurate. The distance between asteroids is so large navigating between them is easy. I expect there will be many comparisons between NEAR’s landing on Eros, Hayabusa2’s two samplings and impact and OSIRIS-REx’s data.

Very much so. This was one end member in our simulations, though we never seriously expected it to penetrate that far. However, the back away thruster ignition timing was designed to prevent the the instrument deck from making contact in the unlikely event that what happened happened. Maybe, there is still nothing to hold on to, also we don't know how typical this spot was. Analysis is coming, but first the science and engineering team is working together to stow the sample.

Thank you. The samples are ours. Anyone with a good idea and a proven technique can request samples to analyze for decades after the return, just like Apollo samples.

Yes, that's the point of this thread; see the first posts. I'm the Project Scientist for OSIRIS-REx, the Senior Scientist for Astrobiology at in the Solar System Exploration Division at NASA Goddard Space Flight Center (and formerly Chief of Astrochemistry), and Director of the Goddard Center for Astrobiology. My research is studying organic material in extraterrestrial samples, though I've done other non-sample work. I don't study iron meteorites (much, we have a paper under review now). But studying material older than the Earth is thrilling, and knowing that my analyses destroy the sample is humbling. I also play KSP, but not very well nor very often. But as a chemist, I can attest to the accuracy of xkcd's assessment.

Thanks, and no problem. I analyzed Stardust material and OSIRIS-REx is derived from Stardust (and not Genesis) so it’s personal

You are confusing the Genesis mission to collect solar wind with Stardust which collected dust from comet Wild 2. Stardust landed perfectly. Genesis had a g-switch installed backwards so the parachute didn't deploy and it crashed. The science was recovered from Genesis, but it took a lot of extra work and time. Legend has it that the review that could have caught the backwards g-switch was cancelled because of the 1996 government shutdown. Both Stardust and Genesis were designed under NASA's Faster, Better, Cheaper philosophy, where the goal was to have more lower cost missions with less testing, and accept the potential failures. The philosophy has a problem when the public does not understand that some level of failure is expected as the price of more missions for the same budget.

We’ll stow it, but every lost particle makes me sad. We could be losing more than the sum of every other non-lunar sample return mission combined.

As an organic analytical chemist, I'm more excited about the former.

This is definitely NOT an animation. It is a series of still images stacked into a video. Compare the number of particles in the video to the cgi visualization published before TAG to see the difference between real images and animation.

Nice. The first lunar surface image would be Luna 9's

Remind me what GIT stands for. But here is probably more information than you want about the spacecraft https://link.springer.com/article/10.1007/s11214-018-0521-6

Tune in at 5 pm EDT tomorrow! View this email in your browser October 19, 2020 Tomorrow is TAG Day! Tomorrow -- October 20 -- the OSIRIS-REx mission will perform the first attempt of its Touch-And-Go (TAG) sample collection event at asteroid Bennu. Watch on NASA TV starting at 5 pm EDT, and follow along with the OSIRIS-REx Twitter account for a live play-by-play of TAG. In the meantime, keep following the OSIRIS-REx Twitter and Facebook pages for updates on the various activities surrounding this historic event. We look forward to sharing the excitement with you! The TAG Event Sequence Tomorrow, the spacecraft will leave its safe-home orbit to begin the journey to Bennu's surface. It'll perform the Checkpoint and Matchpoint burns to steeply descend to the surface, and then... it's time to collect a sample from site Nightingale! Download the poster to follow along. Read more about what to expect from TAG here. OSIRIS-REx in Real-Time Watch the spacecraft's activities like you're a member of the mission operations team! Stream the real-time engineering simulation of the sampling event starting at 1:22 pm EDT here. TAG is TRICKY! Wondering just how difficult it is to grab rocks off a tiny asteroid? The straight answer is… it's very difficult. But check out this video on how the OSIRIS-REx team has risen to the challenge. Take a Tour of Bennu Scientists had expected Bennu’s surface to consist of fine-grained material like a sandy beach, but were instead greeted by a rugged world littered with boulders – the size of cars, the size of houses, the size of football fields. Now, thanks to laser altimetry data and high-resolution imagery from OSIRIS-REx, we can take a tour of Bennu’s remarkable terrain. Follow Us At:

Some nice quotes for you at https://youtu.be/rNZjogVTmAM?t=1552 115 maneuvers, the most recent burn was 0.5 mm/s