OSIRIS-REx Asteroid Sample Return

[IonStorm]

1 minute ago, tater said:

What happens if there are larger debris that are detected with the SamCam that might interfere with stowage?

Those are two different things.  First, the particles observed by NavCam 1 are being studied with great intensity both for scientific discovery and to ensure spacecraft safety.  Second, we have done analysis to ensure spacecraft safety when particles are liberated during collection as well as contingency plans if interfering debris is observed prior to stowage by SamCam and StowCam.  

We will also be watching our JAXA colleagues for lessons when they collect their sample from Ryugu 2/22/19 06:45-09:15 Japan time (2/21/19 16:45-19:15 Eastern)  http://fanfun.jaxa.jp/jaxatv/detail/14034.html

[tater]

17 minutes ago, IonStorm said:

as well as contingency plans if interfering debris is observed prior to stowage by SamCam and StowCam.  

That's what I was getting at, I guess. If there's a troublesome rock chip, is it shaken lose with the gas used to collect particles in the first place, or is the spacecraft spun up, the arm shaken, or some combination

I assumed there were plans for virtually every possible problem.

That said, the close mapping images are going to be pretty amazing in and of themselves. An exciting couple years ahead!

Edited February 18, 2019 by tater

[tater]

Awesome image:

https://www.asteroidmission.org/mapcam-north-pole-20190220/

Quote

MapCam View of Bennu’s North Pole from Orbit

This image shows a region near asteroid Bennu’s north pole on the terminator line between the asteroid’s day and night sides. The OSIRIS-REx spacecraft’s MapCam camera obtained the image on Feb. 20 while in orbit around the asteroid from a distance of 1.1 miles (1.8 km). At this distance, each pixel covers approximately 4.5 inches (12 cm) of Bennu’s surface. The largest boulder, located slightly left of the center, measures around 52 feet (16 meters) across, which, for scale, is the length of the trailer on a semi-truck.

During the mission’s orbital phase, OSIRIS-REx circles the asteroid near Bennu’s terminator line. While this positioning helps maintain the spacecraft in a stable orbit, the half-light/half-dark view of the asteroid creates challenging conditions for science imaging.

Date Taken: February 20, 2019

Instrument Used: OCAMS (MapCam)

Credit: NASA/Goddard/University of Arizona

 

[IonStorm]

More images https://www.asteroidmission.org/2019-02-25-regolith-image-compilation-3/

A Region of Bennu’s Northern Hemisphere Close Up

This trio of images acquired by NASA’s OSIRIS-REx spacecraft shows a wide shot and two close-ups of a region in asteroid Bennu’s northern hemisphere. The wide-angle image (left), obtained by the spacecraft’s MapCam camera, shows a 590-foot (180-meter) wide area with many rocks, including some large boulders, and a “pond” of regolith that is mostly devoid of large rocks. The two closer images, obtained by the high-resolution PolyCam camera, show details of areas in the MapCam image, specifically a 50-foot (15 meter) boulder (top) and the regolith pond (bottom). The PolyCam frames are 101 feet (31 meters) across and the boulder depicted is approximately the same size as a humpback whale.

The images were taken on February 25 while the spacecraft was in orbit around Bennu, approximately 1.1 miles (1.8 km) from the asteroid’s surface. The observation plan for this day provided for one MapCam and two PolyCam images every 10 minutes, allowing for this combination of context and detail of Bennu’s surface.

Date Taken: Feb. 25, 2019

Instrument Used: OCAMS (MapCam and PolyCam)

Credit: NASA/Goddard/University of Arizona

[Nightside]

Incredible!

[IonStorm]

There will be more exciting information at a press conference next week.  https://www.nasa.gov/press-release/nasa-to-host-media-teleconference-on-asteroid-sample-return-mission

[tater]

 

Edited March 18, 2019 by tater

[IonStorm]

Various Surface Textures of Bennu’s Boulders

The boulders on Bennu’s surface sport a variety of surface textures, from smooth, to hummocky, striated, and crumbly “cauliflower” in nature. The large boulder in the image center is ~92 ft (~28 m) across and has a somewhat round shape, though many smaller boulders surrounding it are very angular. Some of these appear to be fragments that may have disaggregated from the central boulder and display layering effects that may reflect some of the properties of their mineral composition. Other boulders show signs of surface exfoliation and fractures that may have been caused by impacts, mechanical weathering, and other forms of rock breakdown active on Bennu’s surface. 

This image was obtained by the MapCam camera on NASA’s OSIRIS-REx spacecraft on February 27 from a distance of 0.8 miles (1.3 km) and shows a region of the asteroid’s southern hemisphere near its south pole.

Date Taken: Feb. 27, 2019

Instrument Used: OCAMS (MapCam)

Credit: NASA/Goddard/University of Arizona

https://www.asteroidmission.org/20190227t002051s742_map_iofl2pan/

[IonStorm]

Here’s some news in this thread. 

 

[tater]

18 minutes ago, IonStorm said:

Here’s some news in this thread. 

Wow, that's fascinating.

What are the implications for reducing the data you guys get from sample return, since the surface material is perhaps refreshed at some rate by material ejected from the interior of Bennu? When material erupts, is there any way to do spectroscopy on the (presumed by me) gas doing the ejecting?

[IonStorm]

21 minutes ago, tater said:

Wow, that's fascinating.

What are the implications for reducing the data you guys get from sample return, since the surface material is perhaps refreshed at some rate by material ejected from the interior of Bennu? When material erupts, is there any way to do spectroscopy on the (presumed by me) gas doing the ejecting?

We have a campaign this summer, but the particles are small 1 to <30cm

Our earlier plume campaign was negative, so the gas (if that’s the mechanism) isn’t abundant. But we’ll try. 

It is exciting for return 

[tater]

Live now:

 

[tater]

46 minutes ago, IonStorm said:

We have a campaign this summer, but the particles are small 1 to <30cm

Our earlier plume campaign was negative, so the gas (if that’s the mechanism) isn’t abundant. But we’ll try. 

It is exciting for return 

The new sample target area diameter points out that "pond" as a size example---is there any concern (or hope, lol)  that such an area might be a site of the outgassing/eruptions?

Have the sites of the eruptions been established well enough to have a feel for any geographical preferences they might have, or are they randomly scattered?

 

 

[IonStorm]

1 minute ago, tater said:

The new sample target area diameter points out that "pond" as a size example---is there any concern (or hope, lol)  that such an area might be a site of the outgassing/eruptions?

Have the sites of the eruptions been established well enough to have a feel for any geographical preferences they might have, or are they randomly scattered?

 

 

We don’t know yet, but we’re working on it. 

[tater]

Wow:

 

[IonStorm]

Remember this is a composite. The particles are too dim to see without hugely overexposing Bennu. 

[tater]

2 minutes ago, IonStorm said:

We don’t know yet, but we’re working on it. 

I saw that image and wondered if a shallow depression might be a vent, lol.

I guess this preocess also explains why there are only a few, larger impact features. The rest might be covered by lower velocity eruption events, I suppose (with the debris slowly falling back to Bennu).

The universe is an interesting place. Even what people might assume to be a tiny, boring rock is anything but boring.

[cubinator]

Now that's unexpected. Every place we visit reinforces for me the idea that space is every bit as exciting as science fiction makes it seem.

[ThatGuyWithALongUsername]

16 minutes ago, cubinator said:

Now that's unexpected. Every place we visit reinforces for me the idea that space is every bit as exciting as science fiction makes it seem.

Yes. This. Space is so cool, even random rocks or floating piles of rubble have active mini-volcanism, or are contact binary disc shaped, or have moons... etc.

 

There's just so dang much to explore... we haven't even scratched the surface yet- and that's an understatement if anything!

(I wonder if Ryugu has this, too, and if it doesn't maybe that will help us figure out what's causing this, given their similarities and differences)

[IonStorm]

2 minutes ago, ThatGuyWithALongUsername said:

(I wonder if Ryugu has this, too, and if it doesn't maybe that will help us figure out what's causing this, given their similarities and differences)

Ryugu has not been observed to be active, though images at the specific camera angles that made them apparent for OSIRIS-REx (for improving navigation accuracy) have not (yet) been taken by Hayabus2.  However, the hydration bands in the infrared are much weaker in Ryugu than Bennu and the magnetite features are absent in Ryugu.  This points to a Bennu being wetter, which might be the mechanism for ejecting particles while at perihelion.  

[tater]

Fun image. Cross your eyes til you see three images, then focus on the center image that results. (click image to enbiggen it )

 

[IonStorm]

1 minute ago, tater said:

Fun image. Cross your eyes til you see three images, then focus on the center image that results. (click image to enbiggen it )

You can also put it on your phone and use a (cheap) VR headset to see it.

[StrandedonEarth]

6 hours ago, tater said:

Fun image. Cross your eyes til you see three images, then focus on the center image that results. (click image to enbiggen it )

That was awesome. Zoned right into it.

[IonStorm]

This might be good enough for RSS.

This is also the shape model we are superimposing image data on, so it is professional grade (until we get a lidar based one in the summer). 

https://www.asteroidmission.org/updated-bennu-shape-model-3d-files/v20_shapea_24fps_sm_1/

Also, if you want the latest science here are a series of manuscripts just published (many behind paywalls, but per NASA policy all will appear here after a proprietary period: https://www.ncbi.nlm.nih.gov/pmc/funder/nasa/)

• The unexpected surface of asteroid (101955) Bennu https://rdcu.be/btlxy
• Craters, boulders and regolith of (101955) Bennu indicative of an old and dynamic surface https://rdcu.be/btlx8
• The dynamic geophysical environment of (101955) Bennu based on OSIRIS-REx measurements https://rdcu.be/btlxX
• The operational environment and rotational acceleration of asteroid (101955) Bennu from OSIRIS-REx observations https://rdcu.be/btlxS
• Evidence for widespread hydrated minerals on asteroid (101955) Bennu https://rdcu.be/btlxR
• Properties of rubble-pile asteroid (101955) Bennu from OSIRIS-REx imaging and thermal analysis https://rdcu.be/btlxL
• Shape of (101955) Bennu indicative of a rubble pile with internal stiffness https://rdcu.be/btlxI

 

[tater]