Planetary Resources

[JohnFornaro]

What about the rate of lazy tumbling?

Light curves can give rotation rate.

Diameter?

You can get a decent estimate, especially if you have mid IR data. This was one of the big contributions of NEOWISE.

Mass?

Not easily unless it has a moon, which a fair fraction of NEOs do. Of course you can get a ballpark from the size estimate and knowledge of other bodies with similar spectral type.

A flickering point of light can only give but so much info.

Most astronomy is done on flicking points of light

The other thing to keep in mind is that survey and followup will be done by different instruments. From what I gather the first generation Arkyds will be intended for survey.

All of that is just fine.   It is indeed a romantic notion about the flickering points of light which interest astronomers.  They always ask for more resolution.  A flickering point of light can only give but so much info.

The point stands that resolution is of crucial importance towards the whole picture of selecting the most desirable rock for this pressing purpose.

Or is an argument being made that the Arkyd line of satellites should not be improved?

[Robotbeat]

An astronomy professor told me he actually prefers flickering points of light because it makes certain things more straightforward.

[JohnFornaro]

An astronomy professor told me he actually prefers flickering points of light because it makes certain things more straightforward.

Of course, his pre-determined sub-set of those "certain things" has to do with his personal interests, and not at all with the general task of lassoing an asteroid, and putting it to practical use, which at least theoretically, is what PRI proposes.

[yg1968]

Google+ hangout:

http://www.youtube.com/watch?v=1u8KTH1xbLY&feature=youtu.be

[hop]

Or is an argument being made that the Arkyd line of satellites should not be improved?

No, the argument is that Arkyd will obey the laws of physics. If you have a telescope that will fit in the stated Arkyd size class, you aren't going to resolve many asteroids unless you get pretty close. In fact, if you have a telescope in the Hubble size class, you *still* won't resolve many asteroids. Hubble is good to ~0.1 arcsec, which works out to about 200 meters at lunar distance. 200 meters is pretty substantial for an NEO, and they don't spend much time closer than the moon.

According to http://www.planetaryresources.com/technology/ the Arkyd 200 series will solve this by intercepting asteroids that make a relatively close approach to earth.

Orbit, spectra and light curves should be plenty to decide whether to attempt those intercepts.

[jongoff]

It would appear that the very first hardware to be launched by Planetary Resources is NOT a full blown Arkyrd, but rather an early prototype.

Can a 3U CubeSAT be deployed from the Kibo airlock? I would imagine that whoever is handling this deployment for PR will make sure that such a deployment is possible.

JSSOD can handle a 3U, IIRC. And NanoRacks has talked publicly about how they're looking at doing a deployer that can handle even more cubesats than that. There are also some potential ways of handling even larger deployments from ISS, one that's being looked at by a JSC group (called SSIKLOPS) and another two options that Altius is looking at.

~Jon

[QuantumG]

In response to my question, Peter Diamandis confirmed today that it is a Nanoracks contract to launch the Planetary Resources 3U cubesat from the Kibo module next year.

[JohnFornaro]

Or is an argument being made that the Arkyd line of satellites should not be improved?

No, the argument is that Arkyd will obey the laws of physics.

I'm pretty sure that nobody up thread suggested that the satellites wouldn't obey the rules of physics.  Perhaps some straw blew out of the stables.

As I said above:  One technical issue I struggle with is how their camera can have enough resolution to look at the pinpricks; stabilize its view so as to follow multiple pinpricks in order to get valid data on their orbital characteristics; AND... accurately observe the tiny fluctuations in the brightness of the objects so as to accurately characterize their rates of tumble, and somehow note their size and mass.

If you don't want to talk about the part that comes after "AND", that's fine.

Their camera's got to be higher resolution than what  OldAtlasEGuy supposed.  He speculated on a 32megapixel camera, which would not be able to see the rock that is intended to be retrieved.

The PRI problem has not been publicly revised, to my knowledge.  They plan to scan the sky, so far with one Arkyd 100, and find moving points of light.  As you mention, "Orbit, spectra and light curves should be plenty to decide whether to attempt those intercepts." 

At the moment, their current plan is to dilute the orginal capabilities of the first Arkyd100 satellite, roughly in half.  Half the time they'll be looking for asteroids, half the time for exoplanets.  For exoplanets, resolution is their friend, and they will need more of it. 

But they're already diluting the capabilities of their very first satellite from the mission that they tooted so loud on their crowd sourced horn.  In order to carry out the originally advertised mission, they will need higher resolution satellites, or they could trade higher resolution to get up close and personal with one.

According to Jebbo above, "The 2nd $1m is to improve pointing accuracy and to dedicated time to exoplanet hunting, not to launch a 2nd publicly accessible telescope."  The term "publicly accessible" means that they will show the public a selected subset of pictures from what they actually discover.  It does not mean that the public gets access to the joystick which points the satellite.

However, this is inconsistent with Tass' remarks:

...aaaaaand, now we can tell you that it is about launching a kickstarter to finance an extra Arkyd100 for private us.

(Private use?  Not clear)

At least they have a NanoRacks contract for next year.  I'm sure they'll put their first $1M to good use.  Not one hundred percent clear is whether that $1M is for the first Arkyd 100 or the second.

[Robotbeat]

They don't really need resolution for either asteroids or exoplanets. They're looking at lightcurves, which can be used to model the shape and size and spin rate of asteroids (yes, all from a single pixel) and for looking for exoplanet transits again looking at precise timings and the exact light curves to look for other non-transiting planets, the size of the exoplanets, etc. Again, all from a single pixel. You don't need spatial resolution for that. Simply being outside the atmosphere helps a lot.

Exoplanets are (except for very rare exceptions) detected in the following ways:
*looking at periodic doppler shift of the host star's spectral lines
*gravitational microlensing
*from transits
*direct imaging (using some sort of stellar coronagraph)...

Only the last one (and maybe microlensing?) requires lots of resolution (but mostly it's limited by the efficacy of the coronagraph, not resolution per se). They've chosen transit as the detection method (which is most similar to what they're already doing with the asteroid light curves).

I'd imagine they wouldn't try to find the detailed light curves of lots of asteroids at once. I'd imagine that once they've narrowed down the list of targets, they'll look at them one at a time.

And if they track the position of the asteroids very precisely (esp. when it comes near other asteroids), they can pick out the mass from the single pixel as well. Having a full spectrum of the asteroid helps as well, since you can start with the brightness and get a good idea of the size and composition and thus a reasonable estimate of density and thus mass.

[neilh]

I don't think the thread's live yet, but in their email today Planetary Resources said they're doing an AMA on reddit today at 10am PT.

[sublimemarsupial]

Per reddit AMA, they hope to fly the 3U cubesat test bed on SpaceX CRS-4 in April 2014.

[FutureSpaceTourist]

Reddit AMA is at http://www.reddit.com/r/IAmA/comments/1h47je/we_are_engineers_from_planetary_resources_we_quit/

[StephenB]

In response to my question, Peter Diamandis confirmed today that it is a Nanoracks contract to launch the Planetary Resources 3U cubesat from the Kibo module next year.

Thanks QG.

[hop]

Their camera's got to be higher resolution than what  OldAtlasEGuy supposed.  He speculated on a 32megapixel camera, which would not be able to see the rock that is intended to be retrieved.

The bolded statement doesn't follow at all. As others have pointed out, the resolution of the sensor is a relatively minor factor. Google "diffraction limit" if you want to actually understand this. Kepler has a huge ~95MP sensor but does not have particularly fine resolution. Hubble has modestly sized sensors but still gets close to the theoretical limit.

It's stated right on the kickstarter page the telescope will have a 200mm aperture, a "5mp+" sensor. The stated resolving power is ~1 arcsec, which is pretty close to the theoretical limit for a telescope of this size.

The PRI problem has not been publicly revised, to my knowledge.  They plan to scan the sky, so far with one Arkyd 100, and find moving points of light. 

This doesn't isn't what I get from their public statements or the web page I linked. It is clearly stated clearly on the kickstarter that the "crowd funded" telescope is supposed to be one of several, and is not their main asteroid hunting telescope. Their business model involves selling time and telescopes to other people to fund their space mining efforts.

For exoplanets, resolution is their friend, and they will need more of it. 

This is not at all true for the kinds of exoplanet studies they could do with a small telescope. They need better (more stable AFAIK) pointing for exo-planets, not more resolution. Telescopes that do high precision photometry are often designed to be slightly out of focus (Kepler and MOST are examples of this)

[FutureSpaceTourist]

Press release:

3D Systems and Planetary Resources Announce Investment and Collaboration
Innovative collaboration will transform the manufacturing of asteroid prospecting spacecraft

ROCK HILL, South Carolina, June 26, 2013 – 3D Systems (NYSE:DDD) and Planetary Resources, Inc. today announced that 3D Systems has joined Planetary Resources’ core group of investors and will be a collaborative partner in assisting Planetary Resources to develop and manufacture components of its ARKYD Series of spacecraft using its advanced 3D printing and digital manufacturing solutions.

Planetary Resources already has multiple contracts to develop miniaturized and responsive technologies with far-reaching applications to space assessment, accessibility and resource recovery with a primary goal to mine near-Earth asteroids for raw materials, ranging from elements used in rocket fuel to precious metals, through the development of innovative and cost-effective robotic exploration technologies. The companies see additive manufacturing technologies as enabling to the development of future space infrastructure.

“We are excited to work very closely with Planetary Resources’ engineering team to use advanced 3D printing and manufacturing technologies to increase functionality while decreasing the cost of their ARKYD spacecraft,” said Avi Reichental, Chief Executive Officer, 3D Systems. “In success, we will create the smartphone of spacecraft and transform what has been an old-style, labor-intensive process, into something very scalable and affordable that will democratize access to space, the data collected from space and off-Earth resources for scientists and the public.  We are delighted to join the Planetary Resources team.”

Peter H. Diamandis, M.D., Co-Founder and Co-Chairman, Planetary Resources, Inc. said, “We are absolutely thrilled to partner with 3D Systems, the world’s pioneer and leader in 3D printing and advanced manufacturing, as we pursue our vision to expand the resource base beyond Earth. 3D Systems has a long history of inventing, advancing and democratizing manufacturing – and our vision of mass producing the ARKYD 100, 200 and 300 line will greatly benefit from their thinking and technology.”

In connection with this investment, the 3D Systems announced the formation of 3D Systems Ventures, a new investment arm that will identify, seek and manage its seed investments in promising enterprises that will benefit from or be powered by the company’s leading technologies. The venture arm will be headed by Hugh Evans from T. Rowe Price who will join 3D Systems as the Vice President Corporate Ventures.

[JohnFornaro]

Their camera's got to be higher resolution than what  OldAtlasEGuy supposed.  He speculated on a 32megapixel camera, which would not be able to see the rock that is intended to be retrieved.

The bolded statement doesn't follow at all.

You raise some interesting points as usual.  I'll be brushing up on diffraction limits.  BTW, I've already read their K/S page.  I'm sure that they'll revise it as they see fit.

I certainly wish them good luck with their pixels, and offer kudos for being privately funded.

The news about 3D Systems is also interesting:  Once they figure out the 3D printing part, then the liklihood of there being mass produced "fleets" of satellites at low cost increases.

Call it what you want, but the more sats they can get out there, the better their chances of resolving the issue of which ones are worth lassoing.

[BrightLight]

Their camera's got to be higher resolution than what  OldAtlasEGuy supposed.  He speculated on a 32megapixel camera, which would not be able to see the rock that is intended to be retrieved.

The bolded statement doesn't follow at all.

You raise some interesting points as usual.  I'll be brushing up on diffraction limits.  BTW, I've already read their K/S page.  I'm sure that they'll revise it as they see fit.

I certainly wish them good luck with their pixels, and offer kudos for being privately funded.

The news about 3D Systems is also interesting:  Once they figure out the 3D printing part, then the liklihood of there being mass produced "fleets" of satellites at low cost increases.

Call it what you want, but the more sats they can get out there, the better their chances of resolving the issue of which ones are worth lassoing.

From what I've read, I doubt the 100 series will be diffraction limited, it seems they want to have "fat" pixel pitch on the focal plane (on order 10 micros wide) - high sensitivity in the visible and near IR at the expense of spatial resolution. This makes sense if you want to separate bodies by albedo, as was described in there blog site - distinguish between C-class and M-class. To do this they don't need to resolve the body, what they need is a fast, sensitive focal plane and filter wheels or focal plane spectral arrays with wide 100nm bandwidth channels. They could do it with three channels or bands but will work better with six channels.

[jebbo]

From what I've read, I doubt the 100 series will be diffraction limited, it seems they want to have "fat" pixel pitch on the focal plane (on order 10 micros wide) - high sensitivity in the visible and near IR at the expense of spatial resolution. This makes sense if you want to separate bodies by albedo, as was described in there blog site - distinguish between C-class and M-class. To do this they don't need to resolve the body, what they need is a fast, sensitive focal plane and filter wheels or focal plane spectral arrays with wide 100nm bandwidth channels. They could do it with three channels or bands but will work better with six channels.

I expect large pixels also gives them a better noise floor which would allow longer integration times and a higher magnitude limit (higher = fainter). 

[BrightLight]

From what I've read, I doubt the 100 series will be diffraction limited, it seems they want to have "fat" pixel pitch on the focal plane (on order 10 micros wide) - high sensitivity in the visible and near IR at the expense of spatial resolution. This makes sense if you want to separate bodies by albedo, as was described in there blog site - distinguish between C-class and M-class. To do this they don't need to resolve the body, what they need is a fast, sensitive focal plane and filter wheels or focal plane spectral arrays with wide 100nm bandwidth channels. They could do it with three channels or bands but will work better with six channels.

I expect large pixels also gives them a better noise floor which would allow longer integration times and a higher magnitude limit (higher = fainter). 

this is correct and the large pixel pitch will decrease "shot noise" and pixel to pixel cross talk.

[jebbo]

this is correct and the large pixel pitch will decrease "shot noise" and pixel to pixel cross talk.

I'll be interested to see what the point spread functions for each pixel look like (dilution is an interesting issue with Kepler data and can lead to underestimation of the size of planet candidates; for asteroid detection it probably matters much less but might make spin rate determination harder). 

And cross-talk -- charge bleed produces some whacky light curves!

[ guess which stretch goal I'd like to see but that is darned unlikely:-) ]

--- Tony