Category Archives: Asteroids!

Bennu, Not a Potato This Time

This week has humanity reaching out to another asteroid, this one named Bennu, the target of the OSIRIS-REx spacecraft. Bennu is not content to be a tumbling potato in space, but is rather geometric in shape, with even some flat facets that are eerily regular in appearance. One wonders what mechanism has produced such an enigmatic shape.




Bennu from about 50 miles away. (Click the image to see an animation.)


If all goes well, we’ll be getting a sample of the rubble-like surface in September 2023, and it may be some of the oldest stuff in our solar system. For more information, see:

Mars Study – Oldie But Goodie

Robert Zubrin’s The Case For Mars (TCM) has been in publication for a couple of decades now, and is a seminal work in the space advocacy genre. Really, it shares space next to weighty volumes like those from Carl Sagan and Gerard K. O’Neill.

It has occurred to me more than once that it would be useful to design an academic course around such books, with TCM as the main reference in this case.  So, that’s what I’m going to embark on now. I’ve just picked up the newest edition and will give it as solid an evaluation as I  can and start generating course materials. 

Ares vs. Luna – Should the Siblings Fight?

I am a very long-time supporter and member of the Moon Society, from way back in the 1990’s, and feel pretty strongly about the need to establish a beachhead on the Moon. There are a number of reasons for this.

It’s stable.

From an orbital consideration, it is an extremely well-known commodity. Many nations have now landed something on the moon, orbited it, or used it as a means of sling-shotting to some other place in the Solar system. We know how to get there, and how to maneuver around it. There is something to be said for consistency. Geologically, it is nearly silent, and between industry and science, the nearly lab-like conditions and vast tableaus have a great deal of value.

It isn’t new.

I know, this doesn’t sound like a great selling point, but hear me out. With the Apollo missions, the Moon has been characterized enough in a few surface locations to build upon, if one takes a more cautious exploration strategy. For all of those detractors of the “flag-n-footprints” nature of the Apollo program, what better way to make lemonade than to actually derive a better and longer-lasting program of habitation based on what we’ve already learned?

It’s geopolitically valuable.

Humans will be humans, and sometimes they will fight. Maybe an economic war, or maybe a hot war, but nations are going to be at opposition of some level at all times in human history. Get used to it. As such, what value can be made of the Moon will initially belong to who lives there first. And I mean lives there, not explore or take a vacation there. Some nation, someday, will claim the place. Functionally, it provides a low-g jumping off point for other places. Militarily, it is the ultimate high ground in the Earth-Moon system. Woe is it to those who lose that race to a belligerent foe.

Of course, in the logic of zero-sum mathematics, there are a lot of people who think that in a finite field of funds, going to the Moon is stale and wasteful compared to Mars. If that is the logic in play, then Mars is also a bad place to go, because Asteroids have a very good chance of repaying the development costs and then eclipsing them in short order. Much shorter than Mars.

But really, the division between the two is a matter of apples-and-oranges, and does nothing but cause feuds between the proponents of the two destinations. As far as I am concerned, if the Triad is the road to the rest of the Solar system, colonizing the Moon is the maturing of the Terrestrial system. Certain circles are taking umbridge that NASA is doing quiet study on going back there, but personally, I think it’s great. I think it’s appropriate. However, Mars missions push us towards technology that we need to go anywhere else nearby, say the moons of Jupiter or Saturn, or even farther afield. Why throw such activity out in a fit of Lunachauvinism, either?

NASA is supposed to look to the future, and it is kind of unrealistic to think that planning for Moon missions would be ignored. Lunar activity doesn’t become any more or less impractical because political winds blow in another direction. Going to Mars is something else we need, too, so we can spread ourselves out and protect the species, and to foster freedom.

Reasons to ARM Wrestle – Item 10

Leaving something permanent.

One of the saddest things about the Apollo missions is that they didn’t leave anything permanent that made future missions any easier. When Apollo was canceled, all that was left were museum pieces, pictures and a few hundred kilograms of rocks. But the nice thing about ARM is that once the asteroid sample has returned to lunar DRO, it’s there. It doesn’t require continued expenditures from NASA for it to stay there. Until we’ve mined every last bit of it, it’s going to be there orbiting the moon, close enough that almost any spacefaring country or business in the world can reach it if they want to. It doesn’t need an ongoing “standing army” that can be defunded. It doesn’t need a mission control to watch over it 24/7. It doesn’t need a sustaining engineering contract that’s going to suck up significant portions of NASA’s limited human spaceflight budget on an ongoing basis. It’s just there. Having something that accessible and permanent out there is worth something, at least to me.

This may be one of the best rationales in the whole ARM mission plan. If we want to have a permanent presence in space, we have to do permanent things. I am an absolute fan of the Apollo program, for a number of reasons, be it political, entertainment, inspiration, or technological and scientific. It was a great period in our nation’s history, and has importance beyond itself as a political tool. But Goff is right: it didn’t last. With significant funding, it could have been built to last, but it was primarily a political program, and when the holders of the purse strings had wrung what they wanted out of it, they moved on. All big programs face such a peril.

But ARM? It has the real potential to develop an infrastructure that can endure, and has practical reasons for why it should endure. We would be building a space exploitation milieu that is focused on resource development, as a product and a way to expand human activity to the solar system in an understandable way. If you want to create something that really lasts, you have to make it of practical value to as many people as possible. You have to show that practicality in a clear, unspun way. We can do that with a strong ARM.

Reasons to ARM Wrestle – Item 9

Providing more experience with on-asteroid operations.

If the Rosetta/Philae mission should tell us anything, it’s that there’s still a lot to learn, from an engineering standpoint, about how to operate successfully on the surface of large, low-gravity objects like asteroids or comets. While we’ll continue to get some small-scale experience using other robotic missions, and while a manned mission to a “free-range” asteroid will also provide a good way to get more data, ARM will likely extend our knowledge about how to do operations like these safely with large objects, increasing the likelihood of success of future manned missions to free-range asteroids.

This topic ties back to something that I think some other commentators are missing, and that is there is nothing wrong with practicing at the Moon first for operations that take place in much more remote locations. It is eases the program into risk, while actually stretching boundaries that we haven’t expanded before. There are those that advocate living on the Moon before reaching for Mars, simply because there are a number of unknowns about how to even merely logistically address a Martian mission. I would generally be one of those advocates. The same applies for a post-ARM crewed rendezvous with the delivered asteroidal object – let the robots go far to the regions where higher risks lie, and bring a part of that environment back to us for study at the relatively nearby Moon. We still get the experience of getting to the Asteroids, we still get to stretch ourselves with a Lunar mission with high mission durations, and likely develop a permanent presence in cis-lunar space, all as bonuses to the basic goal of providing a proving ground for asteroid exploration and development. There are enough gremlins in the Earth-Moon system as it is to keep us quite busy, and as Goff points out, there are enough unknows with asteroid rendezvous punctuated by the experience of the Rosetta team. Heading directly to the asteroids isn’t necessary from the point of view of solar system expansion. Setting up an R&D location in the Lunar location is a very valuable idea.*

We have the Mercury-Gemini-Apollo model to fall back on to understand why this is a winning strategy, so why shouldn’t we use it? I see little overtly wrong with heading back to the Moon to stay, or even a dash to Mars, though the latter may be a flag-and-footprints effort as Apollo became, if there isn’t an infrastructure behind it. Pursuing ARM can be implemented to provide that infrastructure.

*I have no problem at all with a direct-to-the-Moon colony, or a sprint to Mars, or sending crews to the asteroids. I think those are ALSO very valuable ideas. Any of those missions are better than the handwringing of politicians in what passes for the so-called “leadership” demonstrated at the current time.

Reasons To ARM Wrestle – Item 8

Providing the beginnings of a lunar gateway.
It turns out that getting to and from lunar DRO, and to the lunar surface from a lunar DRO, isn’t massively different from getting to and from Earth-moon L1 or L2. The orbital dynamics are a bit more complex but the propellant and travel times are relatively similar. And some lunar DROs can be long-term stable without active station-keeping. If we were ready to go straight to the moon, L1 or L2 might be slightly preferable to a lunar DRO as a location for a lunar gateway, but if we did something like ARM, with the habitat module, you’d already have a de facto start to a lunar gateway — one that likely would be set up (by NASA or follow-on efforts) with ISRU hardware and include at least rudimentary rocket fuel storage and handling capabilities.
For those unaware of Distant Retrograde Orbits (DRO) they are, simply put,orbits that are placed at a significant distance altitude from the body they orbit, and at a direction of travel opposite of that parent body. They are typically very stable orbits, and ARM Option B intends to use a Lunar DRO (LDRO)* to capture the retrieved asteroid boulder around the moon for the later crewed rendezvous.
I will have to give Goff the benefit of the doubt on this, as I don’t have a grasp of the differences between the orbital dynamics of LDRO and Lagrange points. That said, I suppose if the differences really aren’t that great and the logistics likewise not much different, I could certainly see an opportunity to bootstrap an early gateway capability. The real challenge here is to convince mission planners to include the gateway capability into the ARM plan. I don’t know that it is something we can sort of just scab on later, or at least doing so without pre-planning for it is likely to cost more.
*I have also seen the term Selenian DRO (SDRO) used, I am not sure yet what the most common convention for this term actually is. Time will tell.

Triad – Three Technologies Unite for Mars

VASIMR Plasma Propulsion
Small Fusion Systems
Asteroid Retrieval

In the past few months the three items of my extreme interest have hit the news, and it has me pondering if NASA may be putting together (finally) a real set of architectures for a larger solar system mission. The most recent news about Dr. Franklin Chang-Diaz’s Ad Astra VASIMR getting the go-ahead for a mission seemed like a final puzzle piece falling into place. See:

Could we get to Mars in 39 DAYS? Nasa selects companies to develop super fast deep-space engine

If a mission to places farther than Earth orbit or Mars are to become anything other than naked, skin-of-the-teeth exploration forays, we will have to have propulsion sources like VASIMR. You need something that can cross these larger distances quickly, be reusable and re-directable to multiple destinations, and be able to perform an abort is something goes wrong. VASIMR is capable of doing all of those things.

There was also the news late last year about Lockheed Martin’s small, but high-power-density fusion power plants now in development, discussed here:

Fusion Power May Be On Its Way (Finally)

In short, these are the power systems VASIMR is looking for. They make the mission work.

And now we have OSIRIS-REx going forward with spacecraft assembly for its 2016 launch, announced right on the heels of Asteroid Retrieval Mission (ARM) option B being given the green light for development.

The combination of these three things, the Triad, are the road for development of the solar system. Resource exploitation and permanent human exploration and settlement ride that road.

It May Not Be ARM Option B, But It Helps Light The Way

For more background on this mission:

The Origins Spectral Interpretation Resource Identification Security — Regolith Explorer spacecraft will travel to a near-Earth asteroid, called Bennu (formerly 1999 RQ36), and bring at least a 2.1-ounce sample back to Earth for study. The mission will help scientists investigate how planets formed and how life began, as well as improve our understanding of asteroids that could impact Earth.

OSIRIS-REx is scheduled for launch in late 2016. As planned, the spacecraft will reach its asteroid target in 2018 and return a sample to Earth in 2023.

It seems that NASA has turned on the part of this project that allows for the construction of the actual spacecraft, so that’s a great bit of news. It is only bringing back a small part of an asteroid, but a lot of what OSIRIS-Rex will do is an analog for ARM Option B.

NASA’s OSIRIS-REx Mission Passes Critical Milestone

Artist concept of OSIRIS-REx, the first U.S. mission to return samples from an asteroid to Earth. Image Credit: NASA/Goddard





NASA’s groundbreaking science mission to retrieve a sample from an ancient space rock has moved closer to fruition. The Origins Spectral Interpretation Resource Identification Security Regolith Explorer (OSIRIS-REx) mission has passed a critical milestone in its path towards launch and is officially authorized to transition into its next phase.

Key Decision Point-D (KDP-D) occurs after the project has completed a series of independent reviews that cover the technical health, schedule and cost of the project. The milestone represents the official transition from the mission’s development stage to delivery of systems, testing and integration leading to launch. During this part of the mission’s life cycle, known as Phase D, the spacecraft bus, or the structure that will carry the science instruments, is completed, the instruments are integrated into the spacecraft and tested, and the spacecraft is shipped to NASA’s Kennedy Space Center in Florida for integration with the rocket.

For More…

Reasons To ARM Wrestle – Item 7

Developing technologies for a Phobos/Deimos large sample return.

One of the keys to affordable exploration and settlement of Mars will be determining if Phobos and/or Deimos have water in them, and if so, how to extract it efficiently. Having a large source of propellant feedstocks available in Mars orbit (for supersonic retropropulsion on landing, hydrogen feedstock for surface ISRU, and Earth-return propellant) could significantly reduce the amount of propellant needed for both round-trip and one-way Mars missions. If Option B is selected, and if it is designed properly, it would be possible to use the same hardware to capture and return a decent-sized sample — more than 1 metric ton — to lunar distant retrograde orbit (DRO) for evaluation and hopefully ISRU process development/debugging.

There is an operationally rough descent to Mars, due to the sparse Martian atmosphere. We really can’t rely on an Earth-like reentry using aerodynamic forces and parachutes to slow us down. Of course, this means using copious amounts of propellant to slow down large and relatively delicate Mars mission craft for a proper landing on the Red Planet. So do you carry your fuel all the way from Earth, or use ISRU to produce what you need at Mars? The solution here, which I certainly agree with, is ISRU propellant production as a baseline.

With that in mind, if Phobos and/or Deimos can serve as a resource complex, that’s ideal. Goff’s assertion of using the Option B mission as an operational and technological training ground looking forward to Martian resource assays makes good sense. The only area that I disagree at all is an assumption that Option B hardware would be used for the Martian missions. Given the sorts of timelines we are subject to in developing space missions, lessons learned will play a big part in each mission, in the design of every system. Even in the relatively break-neck pace of Apollo, no two spacecraft were the same, there were always upgrades from mission to mission. I’m not really criticizing Goff here, rather I’m just pointing out that the evolution of missions will improve upon Option B successes and failures.

Reasons to ARM Wrestle – Item 6

Demonstrating planetary defense techniques.

If something similar to ARM Option B is selected, NASA is interested in using it to demonstrate the “gravity tractor” method for deflecting the parent asteroid. Learning how to deflect potentially hazardous asteroids is probably one of the more worthwhile things NASA could be spending money on right now, and providing a way of getting real hands-on experience applying those techniques would be very useful.

This is a big one to me, as it is aligns with one of the major rationale for the existence of the Outbound project. Even as a kid, I generally understood that an asteroid or comet impacting the Earth could ruin your whole day. Or your civilization. Or species. Given that seems that having the whole of humanity living on just Earth was never a good long-term plan. I’ve read my share of science-fiction, and books like Rendezvous with Rama and Lucifer’s Hammer drove the point home in good literary fashion, but real-life events in 1994 made it very clear to me that we are living on borrowed time. Comet Shoemaker-Levy 9 collided with Jupiter that July, with some spectacular results.

That comet, fragmented as it was, left multiple impact marks in the atmosphere of Jupiter, including one that was twice the diameter of the Earth. That is impressive, and frankly intimidating, to contemplate. We are fortunate in the extreme that we have Jupiter and Saturn acting as cosmic shop-vacs, clearing much of the debris of the solar system before it reaches the inner orbits such as ours. However, from impact evidence on Earth, not every object is pulled in by our gas giants. If there are rocks out there lurking around that can blot out the Earth so effectively, I can’t imagine why we’d hesitate in getting off of our home rock and leaving more than one target for the cosmos to aim at.

As noted a few days ago here and elsewhere, ARM Option B is now the mission in play, and if it does anything at all to further our ability to get off-planet or divert inbound species-killer object, that’s outstanding.

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