Asteroid approach, Science operations begin! Options

[nprev]

Outstanding!

One of the best parts of watching these live is seeing the joy of the team as years of hard work come to fruition. Congratulations to the people of OSIRIS-REx!!!!

[MahFL]

Awesome. Now to see if they got enough sample.

[Marcin600]

Exciting !!!

From the NASA website:

"The team can’t wait to receive the imagery from the TAG event late tonight and see how the surface of Bennu responded to the TAG event.”

“Our first indication of whether we were successful in collecting a sample will come on October 21 when we downlink the back-away movie from the spacecraft,” Moreau said. “If TAG made a significant disturbance of the surface, we likely collected a lot of material.”

"All spacecraft telemetry data indicates the TAG event executed as expected. However, it will take about a week for the OSIRIS-REx team to confirm how much sample the spacecraft collected."

[Brian Swift]

Anyone have insight into why contact time (2020-10-20 21:50:10) from recent SPICE file
( orx_200827_201103_201019_od292-N-T1D-L-T1R1_v1.bsp )
was a 3 minutes off from actual time which was listed (with added light delay) in a press release on 10/14?

MEDIA ADVISORY M20-113 shows 6:12 p.m. EDT as collection time, -18.52min light travel time gives 21:53 UTC.

[mcaplinger]

Data flowing to the DSN at 900 kbps. Press conference at 2 PM PDT today (10/21) on NASA TV.

[Explorer1]

IMAGES UP:

https://www.nasa.gov/feature/goddard/2020/o...asteroid-bennu/

[Marcin600]

"Upon initial contact, the TAGSAM head appears to crush some of the porous rocks underneath it." (from here)

Dark porous rock crushed by the TAGSAM head (I think so):

Attached thumbnail(s)

 

[fredk]

Aligned on the ground:

[abalone]

Good spray of material with the nitrogen blast. This is what they were looking for to indicate a good potential for a sample

https://youtu.be/LJBv4reH9IU

[Brian Swift]

Here is a re-timed version of TAG images, running about 2-3x realtime. https://youtu.be/6X10esr6Snw

[Explorer1]

The dark shadow of the debris cloud is especially impressive towards the end.
Would any images of the site taken later on to see surface changes? The official website says they are not returning to the vicinity if there is enough sample collected.

After successful stowage, the spacecraft will be put in a slow drift away from Bennu to a safe distance, where it will stay until its departure in March 2021 for the Return Cruise Phase back to Earth.

From: https://www.asteroidmission.org/asteroid-operations/

It seems that any scientific benefit to observing the excavated subsurface is outweighed by spacecraft safety?

[john_s]

I'm having a little trouble understanding the dark background, starting the instant the gas is released and debris starts flying. Is the debris cloud so dense that it instantaneously blocks almost all sunlight from reaching the ground below? I guess that's the case, but it seems surprising. And then why is there such a well-defined edge to the shadow in the final frames? Why does the debris cloud have sharp enough edge to cast a shadow like that?

John

[Brian Swift]

And then why is there such a well-defined edge to the shadow in the final frames? Why does the debris cloud have sharp enough edge to cast a shadow like that?

I assumed the sharp edge shadow at the end was from the rim of the crater that was just created. Would be nice if more images from high up get released before proprietary times up.

I wonder if Bennu is so loosely packed, the a spacecraft could bore a hole all the way through, if it had a sufficient gas supply.

[neo56]

I'm asking the same question John. Some people suggest a crater could have formed due to nitrogen gas expulsion. Wait and see!
By the way, I played myself with the sequence of TAG images. Here I aligned on the ground several pictures taken when OSIRIS-REx moved away from Bennu:
https://www.flickr.com/photos/thomasappere/...292028/sizes/o/

[Marcin600]

Since the shadows in the pictures are to the right of the stones (and not on the left), it seems to me that this big sharp shadow is caused by an object protruding above the surface - such as a nearby large boulder (located to the left and "up" from the field of view).
If it were a depression (the alleged crater), we would see its slope illuminated rather than shaded (shade opposite to that of stones).

So I think it's a big boulder and not a "crater".

All this is combined with a "fuzzy shadow" of a great mass of debris carried away by nitrogen and - above all - by the ship's engines

(picture "borrowed" from neo56)

Attached thumbnail(s)