totm oct 2023 NASA's OSIRIS-REx

[Exoscientist]

NEWS
12 December 2023
‘Head-scratcher’: first look at asteroid dust brought to Earth offers surprises
Researchers have begun examining the pristine space rock collected by NASA’s OSIRIS-REx mission.
By Alexandra Witze
https://www.nature.com/articles/d41586-023-03978-4

  Bob Clark

[AckSed]

My ears pricked up when I saw "phosphate". From what I read, phosphorous is an uncommon element in the Solar System, but to see it on samples from a carbonaceous asteroid (around 75% of all asteroids) is promising for human ISRU in space.

[AckSed]

Just look at the stupendous precision of OSIRIS-APEX's interception orbit. Just... look at it:

 

Side question: how's opening the capsule going?

[PakledHostage]

1 hour ago, AckSed said:

Just look at the stupendous precision of OSIRIS-APEX's interception orbit. Just... look at it:

That final act really is a thing of beauty.

[IonStorm]

53 minutes ago, AckSed said:

Just look at the stupendous precision of OSIRIS-APEX's interception orbit. Just... look at it:

Side question: how's opening the capsule going?

To be fair, this is the anticipated trajectory. As always there will be course correction maneuvers along the way to precisely adjust and make up for any under or over burns. For the rendezvous with Earth last year there were 4 maneuvers (and numerous backups that were not needed) to slowly nudge the spacecraft to Earth intercept and landing on target.  Nevertheless the maneuvers are still remarkable:

• Smallest maneuver 0.1 mm/s; largest 431 m/s
• 10 orbit insertions; 127 deep space maneuvers 
• First frozen orbit at a small body
• 37k optical navigation images
• Lowest orbit (832 m semimajor axis) around smallest object (490 m ave.) 
• One safe mode in 7 years (human error outbound cruise)

Arrival to departure:

Also, your timing is great. The stuck fasteners were removed yesterday! https://blogs.nasa.gov/osiris-rex/2024/01/11/nasas-osiris-rex-team-clears-hurdle-to-access-remaining-bennu-sample/

[PakledHostage]

3 minutes ago, IonStorm said:

• Smallest maneuver 0.1 mm/s; 

I can achieve more than that by eating a black bean burrito...

[AckSed]

13 minutes ago, IonStorm said:

To be fair, this is the anticipated trajectory. As always there will be course correction maneuvers along the way to precisely adjust and make up for any under or over burns. For the rendezvous with Earth last year there were 4 maneuvers (and numerous backups that were not needed) to slowly nudge the spacecraft to Earth intercept and landing on target.  Nevertheless the maneuvers are still remarkable:

• Smallest maneuver 0.1 mm/s; largest 431 m/s
• 10 orbit insertions; 127 deep space maneuvers 
• First frozen orbit at a small body
• 37k optical navigation images
• Lowest orbit (832 m semimajor axis) around smallest object (490 m ave.) 
• One safe mode in 7 years (human error outbound cruise)

A lot of paddling beneath the majestic swan, got it. Even cooler!

 

37 minutes ago, IonStorm said:

Also, your timing is great. The stuck fasteners were removed yesterday! https://blogs.nasa.gov/osiris-rex/2024/01/11/nasas-osiris-rex-team-clears-hurdle-to-access-remaining-bennu-sample/

I find it fascinating that the removal tool, though it's made of a special grade of steel, is similar to an obscure hand-tool that used the pressure from a screwthread to drill through steel... and it uses a quarter-inch Stanley socket.

[Exoscientist]

Team Reveals Remaining Asteroid Sample
Johnson Space Center Office of Communications
JAN 19, 2024

A top-down view of the OSIRIS-REx Touch-and-Go-Sample-Acquisition-Mechanism (TAGSAM) head with the lid removed, revealing the remainder of the asteroid sample inside. 

Photo: NASA/Erika Blumenfeld & Joseph Aebersold

https://www.nasa.gov/image-article/nasas-osiris-rex-curation-team-reveals-remaining-asteroid-sample/

 

 

  Bob Clark

Edited January 20 by Exoscientist

[Exoscientist]

1st look at asteroid Bennu samples suggests space rock may even be 'a fragment of an ancient ocean world'
News
By Leonard David published 2 days ago
'We're going to be busy for a long, long time. This is an enormous amount of sample for us.'
https://www.space.com/asteroid-bennu-osiris-rex-samples-1st-look-surprises

  Bob Clark

[AckSed]

Wait a sec... Bennu's samples have a crust of phosphates. Asteroids like Bennu make up a large proportion of all asteroids. And Earth's atmosphere is under bombardment all the time from meteorites and micro-meteorites.

How much phosphorous is deposited on Earth yearly by these? It's probably miniscule, but over a million years? Two? Fifty? How did almost all mammalian and reptilian life on Earth come to have biological scaffolds utilising phosphates?

[IonStorm]

11 minutes ago, AckSed said:

Wait a sec... Bennu's samples have a crust of phosphates. Asteroids like Bennu make up a large proportion of all asteroids. And Earth's atmosphere is under bombardment all the time from meteorites and micro-meteorites.

How much phosphorous is deposited on Earth yearly by these? It's probably miniscule, but over a million years? Two? Fifty? How did almost all mammalian and reptilian life on Earth come to have biological scaffolds utilising phosphates?

There are other meteorite types with phosphorous (Table 1 https://www.geo.arizona.edu/xtal/group/pdf/EarthScienceReviews_221_2021_103806.pdf). The fairly pure salt is unusual. Some was seen on Ryugu samples as well, but they are different. There is lots of P in the Earth's crust as well. The problem with phosphate is is usually gets bound in insoluble calcium phosphate. Magnesium phosphate is more accessible. There is still a lot of work to figure out the details of the form of phosphate and any organophosphates. 

Phosphate use in biology is far older and more fundamental than animals. Phosphates are a critical subunit of DNA and RNA, lipids, and metabolic intermediates. Here's a classic (and relatively accessible paper if you skip over some of the chemistry) on it https://www.science.org/doi/epdf/10.1126/science.2434996

[Exoscientist]

On 2/8/2024 at 10:51 AM, IonStorm said:

There are other meteorite types with phosphorous (Table 1 https://www.geo.arizona.edu/xtal/group/pdf/EarthScienceReviews_221_2021_103806.pdf). The fairly pure salt is unusual. Some was seen on Ryugu samples as well, but they are different. There is lots of P in the Earth's crust as well. The problem with phosphate is is usually gets bound in insoluble calcium phosphate. Magnesium phosphate is more accessible. There is still a lot of work to figure out the details of the form of phosphate and any organophosphates. 

Phosphate use in biology is far older and more fundamental than animals. Phosphates are a critical subunit of DNA and RNA, lipids, and metabolic intermediates. Here's a classic (and relatively accessible paper if you skip over some of the chemistry) on it https://www.science.org/doi/epdf/10.1126/science.2434996

 Thanks for those refs. You must have done a lot of reading on astrobiology. Interestingly, it has long been known liquid water must have existed or does exist on comets because of the observation of clays and carbonates in carbonaceous meteorites, believed to stem from comets.

Further, evidence of this was provided by the Deep Impact mission to the comet Tempel 1, for which spectrographic observations showed abundant clays and carbonates:

Space
Comet's minerals hint at liquid water
By Maggie Mckee
8 September 2005
https://www.newscientist.com/article/dn7971-comets-minerals-hint-at-liquid-water/

 The question was how liquid water could exist in comets which spend must of their time out in deep space. One theory was radiogenic heating. This is also proposed as an explanation of the liquid water known in the subsurface of the Saturn moon, Enceladus.

 By the way, astrobiology has the unique distinction of being a field of study where you don’t even know the subject exists. My opinion, this question will soon be answered in the affirmative.

  Robert Clark

Edited February 10 by Exoscientist

[IonStorm]

I have done a lot of reading. Though my Ph.D. Is in biochemistry, my career and dissertation  have been on astrobiology (and exobiology when it was called that).  We know from the Stardust mission that there are high temperature grains in comet Wild 2, and presumably other Jupiter family comets. This point to the early solar system being well mixed. There are also minerals that indicate aqueous history (copper iron sulfide) in Wild 2. It could mean cometary micro liquid phases, oceans, or transport from other objects. We need a comet surface sample return mission to find out. The meteorites hypothesized to come from a comet (e.g., CI1 type) but without an unaltered comet to compare against we can’t know. It has been theorized that Ryugu and Bennu are extinct comets. Also note that the distinction between comet and asteroid is fuzzy.  

Edited February 10 by IonStorm

[StrandedonEarth]

43 minutes ago, IonStorm said:

Also note that the distinction between comet and asteroid is fuzzy.  

I see what you did there...

It makes sense, since a comet is merely an asteroid still loaded with volatiles that get baked out into a fuzzy tail when it is close enough to the Sun. It also helps being in a highly elliptical orbit that keeps it frozen most of the time. But of course you know all that.