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NASA's OSIRIS-REx


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21 minutes ago, HebaruSan said:

Harmless operational surprises have been the rule on this mission. The rubble being looser than expected, the sample container overflowing.

I just mean that a higher deploy seems like it should result in a later landing. COurse maybe the whole EDL was slightly shorter. <shrug>

 

Edited by tater
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In the meantime, they talked about it again just now:

"It deployed high. And this is a smart spacecraft, that sample return capsule detected the acceleration rate and it decided that it was important to get that parachute out to slow it down and make this beautiful and safe landing."

Trying to piece together the info, the deceleration at 20000 ft was higher than expected, more like what was expected at 5000 ft. Maybe some atmospheric temperature or density variations?

Sample capsule has been bagged and is being loaded onto the helicopter.
Apparently it's been attached to the helicopter via a line and will be suspended below in flight.

... it's up!

Edited by HebaruSan
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"Very charred" shielding being inspected and cleaned at the clean room facility, prior to entry to the mobile clean room proper:

r0fwGRd.png

I'm not sure what impresses me more, NASA's thoroughness in how carefully 15+ people are going through this procedure, or NASA's transparency in letting me watch the whole thing.

... now in the even cleaner room:

ptUJgWK.png

Edited by HebaruSan
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1 hour ago, HebaruSan said:

I'll get a timestamp and exact quote once the stream wraps up.

1:05:25:

 

Quote

And so we just heard a confirmation actually that the main parachute deployed much higher than was originally anticipated. It was originally supposed to deploy at about five thousand feet elevation, but it actually deployed at around twenty thousand feet, so much higher up, so that would explain our kind of earlier touchdown time than expected here.

As for reconciling this with our intuition, I guess the question is:

Which way way of getting from 20000 ft to 5000 ft is faster: Falling at a more gradual angle without a parachute, or falling at a steeper angle with a parachute? There are enough unknowns in that to make me personally hesitate to make a confident forecast.

I suppose it could also be that the cause was less the parachute and more the higher-than-expected acceleration that caused the parachute to deploy. I'd guess that could be caused either by a denser patch of air in the flight path or a difference in the mass of the sample.

Edited by HebaruSan
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NASA SRC EDL video links to interesting moments:

Spoiler
max heating:
 
main parachute deploy: 
 
pendulum motion of SRC:
 
touchdown---you can see the shadow on the ground (~5 o'clock position)
 
helicopter view at landing site:
 
recovery team arrival:
 
environment sampling team:
 
SRC being packed:
 
SRC packaged up:
 
SRC in heli cargo net:
 
SRC arrival at facility:
 
Arrival Check:
 
Arrival at clean room:
 
Heatshield char:
 
In temporary clean room:

 

 

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5 hours ago, tater said:

Who gets to be in the room when they open the sample, @IonStorm?

Today is preparation for shipping. It is Lockheed technicians (who actually put it together 8 years ago) and JSC curators. At JSC they will open the sample canister and do the formal handoff of the hardware to NASA. The PI will also be watching. Then the slow deliberate disassembly to catalogue and distribute the samples. 

2 hours ago, HebaruSan said:

I'm not sure what impresses me more, NASA's thoroughness in how carefully 15+ people are going through this procedure, or NASA's transparency in letting me watch the whole thing

Thank you. That means a lot. It is very important to share the experience and the science with the world.
And we did rehearse a lot, but so far absolutely flawless. 

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@IonStorm

Why the use of respirators by the ground / recovery crew? 

Seems like a legacy concern from the 50s.

Does masking up actually protect them from anything in a practical sense? 

(I understand the clean room protections - just not the behavior while outside in the desert) 

 

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3 minutes ago, JoeSchmuckatelli said:

@IonStorm

Why the use of respirators by the ground / recovery crew? 

Seems like a legacy concern from the 50s.

Does masking up actually protect them from anything in a practical sense? 

(I understand the clean room protections - just not the behavior while outside in the desert) 

 

The capsule has two lithium-sulfur dioxide  batteries. There is a small chance that they can conflagrate and release toxic gas. So the technicians approach with respirators until their gas sensors show it’s safe. So nothing to do with space or the samples. 

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  • 2 weeks later...
On 9/27/2023 at 2:54 AM, FleshJeb said:

If the asteroid made a faux pas, I hope it's at least a little chon-drite. :D

(Under no circumstances should I be allowed to make puns.)

During the launch campaign there was a team member who has a notorious love of puns. To tease him I submitted the below fake requirement.

Quote

Contaminating language is also a potential risk to the science. The greatest contaminating potential derives from the use of low humor. As such, puns are forbidden around the flight system, launch vehicle, and the OSIRIS-REx team. If puns are required, then a waiver for authorization must be submitted and approved four (4) weeks prior to implementation. The waiver must be approved with concurrence of the Project Manager and the Principal Investigator.

He joked back at a pre-launch review indicating the this requirement had not been met, but without catastrophic consequence. :) 

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Here is the SRC leaving the spacecraft captured by NavCam. The lighting isn't great due to the orientation of the spacecraft needed to aim at Earth. To orient you, glare from the Sun is at the top. The crescent Earth is at the left. The SRC moves from right towards center, you can see it rotating with the connections on the bottom catching the light. In the way are dark blobs buzzing around. These are probably asteroid dust, though ice is also possible.

OREx-SRC-release-sequence.gif

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34 minutes ago, IonStorm said:

Here is the SRC leaving the spacecraft captured by NavCam. The lighting isn't great due to the orientation of the spacecraft needed to aim at Earth. To orient you, glare from the Sun is at the top. The crescent Earth is at the left. The SRC moves from right towards center, you can see it rotating with the connections on the bottom catching the light. In the way are dark blobs buzzing around. These are probably asteroid dust, though ice is also possible.

OREx-SRC-release-sequence.gif

How was the capsule spun up? Part of the release mechanism, I'd guess?

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2 hours ago, IonStorm said:

this requirement had not been met

Great story! 

 

2 hours ago, IonStorm said:

These are probably asteroid dust, though ice is also possible

That is actually fascinating - how would it be ice, if not from the asteroid?

Thanks for the vid, btw - the fact you guys can do this stuff is awesome! 

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1 hour ago, cubinator said:

How was the capsule spun up? Part of the release mechanism, I'd guess?

Exactly. The SRC is attached with a sep/spin mechanism. When the SRC is released the mechanism a spring and screw give the SRC a little push and twist. The spin is for our old friend spin stabilization since the SRC has no guidance or propulsion. 

osirisrex-11.jpg

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18 minutes ago, JoeSchmuckatelli said:

That is actually fascinating - how would it be ice, if not from the asteroid?

There are two possible sources of ice.

1. The most probable is Florida. Water adsorbed on the spacecraft before launch can be lost to space (see https://www.asteroidmission.org/?mission_update=dec-11-2017) but it can also re-condense on the spacecraft. You may have heard of spacecraft doing a rotisserie or barbecue roll which heats the spacecraft evenly and also pushes out water from across the spacecraft.  OSIRIS-REx, like many spacecraft, has instruments which can never be pointed into the Sun to keep the optics from being damaged. OSIRIS-REx went through several "toe-dips" to bring sunlight onto the SRC without shining it directly down the instrument apertures to heat up the SRC and drive water out of the porous heat shield and backshell. But some areas, including the bottom of the SRC is always in shadow. Furthermore, to avoid heating the sample only one brief toe-dip was allowed after sample collection. So water from warmer areas of the spacecraft could migrate to this permanently shadowed region.

2. It is also possible that ammonia produced by the hydrazine monopropellant thrusters could freeze out (-78°C) in deeply shaded regions of the spacecraft. 

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