asteroids Archives - Michael Dello-Iacovo

Xenon and lunar mining – Off-Earth Mining Forum Day 2

I woke up to the very strange sight of sunlight for perhaps the first time since I got to Sydney. With the Future Mining Conference over, all of the talks today were focussed specifically on space.

The first presentation was a review of lunar resources by researcher Ian Crawford, a summary of his paper published in Progress in Physical Geography. With only one or two exceptions, Ian claims, there are no resources on the Moon that would be worth importing back to Earth. The real market would be to use lunar materials on the lunar surface itself, or to use them in cis-lunar space.

Helium-3, touted by many as the solution to all of our energy woes (and the subject of the sci-fi novel by the name of Limit, which I highly recommend despite its 1000+ page length!), is implanted into the lunar regolith by solar wind. But, it only exists at an average concentration of 4 ppb in the regolith. As such, Ian is very sceptical about the economic feasibility of extracting and returning He-3 to Earth. If you’ll allow me to paraphrase him:

“Assuming equal efficiencies, in 1.4 years, the same solar energy falls on 1 metre squared as would be obtained from extracting and processing all the helium-3 contained in the 3 m of high titanium regolith below it.” A rather damning statement.

Some areas of rare Earth elements (REEs) such as uranium and thorium are enriched in some areas, but REEs, despite their name, are not actually that rare, and are certainly not rare or valuable enough to warrant returning to Earth – UNLESS Earth-side supply dropped (e.g. it became too environmentally unfriendly to extract).

A large economy in cis-lunar space (e.g. science, infrastructure, transport, tourism…) may tip the economics over the edge to make lunar exploration and exploitation viable. Note that it takes much less energy to get to Moon escape velocity and down to geosynchronous Earth orbit (GEO) than it does to get to GEO from Earth’s surface. If Moon infrastructure were sufficiently developed, it could become far more cost efficient to build infrastructure in GEO using Moon resources.

This was followed up by Jim Keravala, Chief Operating Officer of Shackleton Energy, who gave us some idea of the infrastructure that might be built in GEO. Shackleton proposes that solar panels, which are much more efficient at collecting energy in space than on Earth, could be built and used to transmit wireless power back to a receiver on Earth’s surface. The energy is non-ionising and thus not a danger to life. This technology is feasible and demonstrated (for example), and can achieve energy transmission efficiencies of around 54%.

Kyle Acierno of iSpace, who are chasing the Google Lunar XPRIZE, gave a quick summary of their progress. The first prize of $20 million goes to the first non-government group to land a rover on the Moon, have it drive 500 metres and broadcast high definition video feed back to Earth. iSpace has developed a small, lightweight rover weighing just 4 kg (compared to the Curiosity Mars rover weighing in at around 900 kg!) to do just this. It is able to be so light because it is purpose built specifically for the prize goals, and contains no science equipment, and it uses 4 wheels instead of the standard 6 for rovers.

Winning the prize is the first step in a long-term plan to spend a swarm of lightweight, cheap rovers to the lunar surface to explore and demonstrate technology, eventually leading to resource extraction and the selling of scientific data. For information about their team and rover click here.

A schematic of the iSpace rover. Apologies for the low res… time for a new camera?

My favourite quote of the day was actually outside a presentation, and consisted of someone loudly exclaiming “No there is NOT more xenon than oxygen in the atmosphere!”

I found out today that the talks were actually live streamed, and you can find some of them here.

I immensely enjoyed the conference – it was a great chance to learn what is happening in the space resource utilisation industry and to meet and collaborate with fellow researchers. For anyone working in this space, or even just interested, I strongly recommend going to the next one in 2017.

Until next time (hopefully before 2017).

Space dust and ethics – Future Mining Conference day 2

Today started at the much more relaxed 8:45 am – not because the conference organisers felt like that was a more appropriate time, but because our Minister for Industry, Innovation and Science decided he couldn’t make it. Or something. I felt doubly snubbed as Pyne is my local MP AND a graduate of my school. C’mon Chris.

There were a lot of great talks today, (and definitely more of a space theme) so I’ll just summarise some of my favourites.

The morning started off with a presentation by Rene Fradet, Deputy Director of NASA Jet Propulsion Laboratory (JPL), on the potential for a common journey between exploration/science and mining in space. My supervisor introduced me to Rene over lunch and we were able to broach the possibility of visiting JPL in California (or even spending some time researching there!?) and collaborating with their scientists, some of whom are also working on mapping the interior of asteroids with geophysics.

Dr Seher Ata from UNSW spoke about ‘Resource recovery in space’, or more specifically, how to process and separate materials in space. If we want to to mine and then utilise material in space without having to bring it down to Earth, we’ll need to develop ways to process and separate materials in a microgravity environment. Many terrestrial separation methods such as froth flotation and magnetic separation rely on gravity. For example, using magnets to separate out magnetic material is only worthwhile if everything else is being pulled away by gravity, and bubbles won’t rise in a liquid, which makes froth flotation difficult to impossible. One audience member suggested centripetal force, but as you add more moving parts you increase the chances of something going wrong. I wondered aloud why we couldn’t utilise that lovely vacuum we have around us in space to induce some kind of air flow/movement and use that instead of gravity. Apparently that wasn’t actually too bad an idea, and I was told to look into it. Geez, I’m just a geophysicist! Let me know if you are a metallurgist and have some clue on how to advance this crack pot idea.

Another good talk was by Dr Jeff Coulton from UNSW Business School about an MBA elective he ran on costing resource projects. To make things a little more interesting, he gave the students a choice between three off-Earth mining projects; mining Ceres, mining the Moon or mining a near Earth orbit asteroid (NEO). The students were mostly from an IT or finance background, and so had little technical experience in terms of space science or engineering. They were told to assume the project was technically feasible, and to make assumptions on costs, resource values, demand etc. This simple experiment suggested that mining the boon had an initial capital expenditure of $9 billion (Au) and a net present value (NPV) of around $-450 billion. So you would lose $450 billion. Not very attractive. But – mining Ceres had a capex of around $22 billion and an NPV of around $80 billion, and mining an NEOhad a capex of just $492 million and an NPV of $295 million. Of course, these assume technical feasibility for these projects, which isn’t necessarily true at present, but what they demonstrate is a strong reliance of economics on the choice of discount rate and selling points.

I was pleasantly surprised to see a few talks on space law, but just plain surprised to see a presentation by an academic on space ethics. He opened his presentation with “As a humanities scholar I’m going to do something that annoys non-humanities scholars, and that is to read to you.” And he did just that. But I must say it was an enjoyable talk which got me thinking about a few things I hadn’t considered. For example, Dr Thom van Dooren focussed on the point that the economic, environmental, technical, scientific and cultural concerns related to space cannot be addressed individually, they are all entangled. Despite the low chances of humanity establishing a backup planet elsewhere, the implications for our survival and expansion are profound. One way to look at this is called ‘worlding’ – “What kind of world are we creating and what are the implications for whom?”

For example, mining helium-3 on the Moon might have obvious positive implications for some, but for others, damaging space environments may be seen as intrinsically wrong, and for others still it may be seen to be offending deities. How do we balance these concerns against others? Van Dooren argues that their concerns are not null.

Professor Steven Freeland began his presentation on space law with an amusing story. He was reading an article about space law in the Wall Street Journal. Oh great, he thinks, this will be interesting. Then he sees the title: “If a Martian crashes into your spacecraft, who is liable?” After a theatrical groan, he decides he can make a better summary of space law than the article.

Dr Alice Gorman gave a unique account of the importance of cultural heritage on the Moon and the implications of Moon dust, which, surprisingly, is actually a pretty big problem. Lunar dust is extremely sharp and abrasive due to the lack of erosional processes such as wind and flowing water. The grains can be highly electro-statically charged, and can levitate, especially when the terminator (sharp night/day boundary on the Moon) passes, due to the rapid change in temperature. Some particles are even assumed to reach lunar escape velocity speeds when human activity such as rover are in the vicinity. Imagine one of these dust grains hitting you at escape velocity!

Images of microscopic lunar dust. Image from commons.wikimedia.org.

Widespread mining of the lunar surface may even create an upper atmospheric dust layer, which could prevent aforementioned particles at escape velocity from actually leaving the surface. The implications of such a feature forming were left for us to imagine!

Apologies to any presentations that I missed, as they were all excellent talks. Leave a comment below or email me if you’d like to hear more about any of the talks, and I can go into more detail and discuss. A list of conference papers can be found via this link.

Tonight featured a presentation by Brian Muirhead of JPL, who is the manager of NASA’s Asteroid Redirect Mission (ARM). I’ll do a separate blog post about that as it’s a mission I’m really excited about, but for now I’d just like to share this very amusing and poignant image.

Maybe the dinosaurs would have survived if they had put more funding into their space program? Let’s not make the same mistake.

The Future Mining Conference finished up today, but the Off-Earth Mining Forum will continue tomorrow, featuring more talks from asteroid mining start ups and space scientists/engineers.

Until then.

The geological mysteries of Ceres

Ceres – a 950 km wide dwarf planet in the main asteroid belt between Mars and Jupiter. As Dawn approached in early 2015 it detected strange bright spots on the surface in a 90 km wide crater later named the Occator Crater. They were so bright they dominated the pixel they resided in on the camera. Now, many months later, NASA’s Dawn team has still been unable to place their origin, though they are finding similar, but smaller, bright patches and streaks all over the surface. Initially, these were predicted to be the result of highly reflective ice, supported by a haze (possibly sublimated water) visible over the bright spots. The best guess at this point is a highly reflective salt, though a mechanism for how and why this salt is exposed at the surface is yet to be confirmed. Possible explanations include surface impacts removing surface material covering the salt (possible for the Occator Crater, but unlikely for the smaller streaks), or some internal mechanism for the salt rising to the surface, which would suggest a geologically active body. Such small bodies have historically been thought to be long since inactive, but Pluto is only 236 km wider and showed remarkable features that are almost certainly due to recent geological activity.

The Occator Crater - showing differences in elevation and the mysterious bright spots. Image from NASA/JPL-Caltech/UCLA/MPS/DLR/IDA. — The Occator Crater – showing differences in elevation and the mysterious bright spots. Image from commons.wikimedia.org.

The surface of Ceres appears to be covered with a hydrated rock alteration product, and may have some areas covered with frost. Thermal models also indicate that Ceres is an icy object subject in the past to hydrothermal activity and differentiation which would give it layers similar to Earth’s inner/outer core, mantle and crust, and even suggest the possibility of a liquid subsurface.

Dawn has generated a topographic map of Ceres’ surface in extraordinary detail. Carol Raymond, deputy mission chief from NASA’s Jet Propulsion Laboratory has noted that the shape of the craters on Ceres are irregular, resembling those on Saturn’s moon Rhea more than those on Vesta, the second largest body in the main belt. A mineral composition map reveals streaks across the surface around the Occator Crater that researchers believe may be relevant.

Topographic map of Ceres showing changes in elevation with a pixel resolution of 400 m. The Occator Crater is located centre right. Image from NASA/JPL-Caltech/UCLA/MPS/DLR/IDA. — Topographic map of Ceres showing changes in elevation with a pixel resolution of 400 m. The Occator Crater is located centre right. Image from commons.wikimedia.org.

Another great unsolved mystery is the origin of the feature known as ‘The Lonely Mountain’, a 6 km high feature with an approximately pyramidal shape. There is no evidence of volcanic activity or plate tectonics on Ceres that might have thrust up such a feature.

The Lonely Mountain. Image from NASA/JPL-Caltech/UCLA/MPS/DLR/IDA. — The Lonely Mountain. Image from commons.wikimedia.org.

I noticed that the mountain is somewhat reminiscent of the centre of some craters on the Moon, for example the crater Alphonsus, pictured below. The centre feature of Alphonsus is also pyramid shaped, but unfortunately the similarities seem to end there. It only rises 1.5 km from the Lunar surface and is surrounded by ejecta material from the impact which created the crater. As seen in topographic images, The Lonely Mountain does not appear to sit within any consistent surface depression the might suggest an impact. It’s possible that subsequent impacts and events have erased evidence of a crater, but if so they have carefully avoided the mountain in the centre. The small crater adjacent to The Lonely Mountain is of approximately the same size and appears to be too close for coincidence. I’m not saying the material from the crater was directly translated to the mountain by some kind of impact, but there may be a relationship.

The Alphonsus Lunar crater. Image from commons.wikimedia.org.

Dawn will cease operations in mid-late 2016 and remain in orbit as a permanent satellite of Ceres. Let’s hope we will collect enough data from Ceres’ surface to solve these questions and more before then.

Australia’s role in an asteroid industry

On the 13th of June 2010, in the Australian outback, the first successfully returned asteroid samples touched down. The Hayabusa 1 mission suffered major technical setbacks, yet many scientific insights were still able to be gleaned from the tiny fragments of the S-type asteroid 25143 Itokawa. The partnership between Australia and Japan for this mission yielded remarkable results and set a top example for future sample return missions. Already, Hayabusa 2 is en route to asteroid 1999 JU3 for another sample return mission, arriving in 2018 and back on Earth in December 2020.

Japan has of course asked Australia if they can land their samples in Australia again. Australia’s response has supposedly been one along the lines of ‘We’ll think about it!’ Given the vast potential for the future of scientific sample return and asteroid mining, it is astounding that Australia take such a passive stance to such a remarkable opportunity, yet is typical of Australia’s space policy of late. If Japan goes elsewhere to land their samples, that would likely be a disaster for future partnerships with Australia.

When the regular iron, nickel and platinum group metal shipments start landing in another country which then reaps the benefits to their transportation and infrastructure industries, perhaps Australia will realise its mistake.

Asteroid mining economics

Hey everyone. I’ve got a few asteroid mining articles to talk about. This article by Jonathan O’Callaghan discusses the asteroid mining plans of Planetary Resources Arkyd 3 Reflight (A3R) CubeSat, which will spend 90 days in orbit testing electronic systems and software. This is an early step in the plans of Planetary Resources to return commercial quantities of resources from asteroids to Earth. The article is somewhat critical of the reality and likelihood of turning a profit through asteroid mining, citing ‘market saturation’ as the reason. Basically by drastically increasing the supply of platinum group and rare earth metals in the market the price will drop (and some asteroids are estimated to have a LOT of PGM and REMs! Atlantis has a total estimated resource value of over 42 trillion dollars!). Therefore the profitability of the PGM and REM industry, both terrestrial and off-Earth, will plummet.

Not a bad argument, and that’s certainly highly likely, but I think the author misses one of the key opportunities of acquiring resources from asteroids. They are already in space. Given that, by my last reading of the value, it costs $50,000 US to put 1 kilogram of material in space due to fuel costs, being able to acquire resources in space and bring them to orbit for less than $50,000 per kg would be a huge boon to the space exploration industry. Even if we can only create fuel initially (by mining water ice on asteroids and using electrolysis to break it down into hydrogen and oxygen, which can then be used as fuel and oxidiser) this can drastically reduce space travel costs. Not to mention that it costs hundreds of thousands of dollars a year to keep a satellite in a stable orbit, making the potential market for space-based fuel huge. Eventually we may even be able to utilise nickel and iron to directly manufacture space equipment in orbit. This article discusses another way that an asteroid mining company can make money. To overcome the market saturation issue, a company could prepare to mine a large volume of PGMs from an asteroid then sell PGM futures, essentially a contract for assets bought at agreed prices but delivered and paid for later. Then when the market is flooded and the price of PGMs drops, they swoop in and buy up all the now cheap terrestrial PGM mining and processing business and infrastructure using their asteroid money. They can then just announce that, due to the price drop, they won’t be mining any more asteroids. The prices will increase and hey presto they’ve just acquired a near monopoly on the terrestrial PGM business. All perfectly legal. Apparently. I think it would be a missed opportunity to only see asteroid mining as returning a resource to Earth. There are other potential ways for an asteroid mining company to supplement their profit. For example, the first company to regularly send probes to asteroids and return material could partner with research organisations and sell data and samples. For more about Planetary Resources’ plan to develop asteroid resources, check out their site here and their Youtube video here on the potentially trillion dollar size of the market for fuel in space. Until next time. Note – I got my figure for the value of Atlantis from Asterank, the Asteroid Database and Mining Rankings.

Pluto, measuring gravity with probe swarms and more!

A lot of exciting space science news coming in this weekend! Lets start with this project brief from Johns Hopkins University.

The proposal is to use a series of orbiting probes and a mothership to measure the gravity field of an asteroid or comet, and use this information to model the internal structure. Modelling the interior of small planetary bodies is something that we haven’t achieved yet as a species, simply because most of our exploration tools focus on large scale and surface features. We haven’t been able to put a drill hole into the centre of an asteroid yet!

Scientists are turning to remote sensing techniques like gravity, ground penetrating radar and radio tomography (think penetrating an asteroid with lightwaves of different frequencies and measuring the signal returning signal bouncing off different internal structures) to cheaply gather data on an asteroid’s interior.

In the above proposal the mothership will precisely monitor the position of the orbiters as they rotate the asteroid. Even a small change in orbit will reveal changes in density which can be caused by heavier or lighter material and empty spaces within. The combined data will be used to build a picture of the asteroid’s interior. This technique is already shown to be feasible through a series of simulations.

The benefits of such a project include the mothership being able to perform other experiments simultaneously, even leaving room to send a lander to the surface.

My only concern is in accurately tracking the position of the orbiters with respect to the asteroids surface. On Earth we need 4 GPS satellites to provide accurate location coordinates.

In other news, an incredible new photo reveals signs of geological features on Pluto, making a geophysicist like myself giddy with excitement. Even with a resolution of 27 kilometres, breathtaking new features can already be made out.

I think my reaction can be neatly summarised by this photo of science team members.

While it is unlikely that Pluto is still geologically active due to its small size, it seems apparent that it underwent a series of events leaving clues on its surface to its past.

As New Horizons principal investigator Alan Stern said, “After nine and a half years in flight, Pluto is well worth the wait.”

Different materials reflect various wavelengths of light in different proportions. As a result, each material has its own characteristic spectral signature.

Even with the most advanced telescopes, the light from distant planets beyond our solar system constitute a single pixel. This makes it hard to look for life, as the light signature from a planet gives us only the average of the near side of the planet.

Researchers from the University of Washington and the Virtual Planetary Laboratory published a paper in May in Astrobiology. They have found that if an organism with nonphotosynthetic pigments (which use light for things other than energy) cover enough of a planet’s surface, their influence on the spectral signature could be strong enough to be detected by a new generation of telescopes currently in development.

This possibility has been overlooked in previous searches for life, and while there are some difficulties with this method, it certainly broadens our ability to detect life at great distances.

A link to the original paper can be found here.

Until next time.

Rosetta and 67P

67P/Churyumov-Gerasimenko, named after its founders by the same names, is rapidly approaching its closest point in orbit to the Sun. At almost 38 km/s to be precise.

Comet 67P/Churyumov-Gerasimenko. Image from wikimedia.commons.org.

Last November, the Rosetta spacecraft’s lander, Philae, became the man-made object to perform a soft landing on a comet.

And what a landing it was! Philae was unsuccessful at anchoring itself to the surface of the comet with its landing harpoons and bounced twice before coming to a halt in a dark zone. This was a problem as the lander couldn’t charge its batteries as well as planned using solar panels, and went into hibernation 3 days after touchdown.

Although Philae made contact at a very low speed, the low gravity on the comet (around one ten-thousandth that of Earth), meant that a small bounce was disastrous.

One proposed theory for the greater than expected ‘bounce factor’ is that the surface of 67P was elastic, with a hard crust under a metre thick overlying an elastic material (S. Ernst pers. comms.). This made me think of the recent announcement that the mysterious ‘craters’ on the surface are created when porous rocky material which has lost its water-ice due to outgassing. Eventually this porous rock can no longer hold its own weight, even in the low gravity of the comet (suggesting high porosity indeed… and a very high current or previous water content for the comet overall!), and it collapses, creating a sinkhole-like feature.

Perhaps the proposed ‘spongy material’ causing Philae to bounce is the same porous rock that is causing these sinkholes?

If so, is the whole surface of the comet poised on the brink of collapse with high porosity? Or did Philae get unlucky and land on a soon to be sinkhole?

These are the questions that excite me about space science. Part of my PhD will involve developing new and novel ways to test various models for the structure of asteroids and comets. Currently I’m looking at seismics and ground penetrating radar, but endless possibilities abound!

Until next time.

Edit: This article suggesting that 67P could be home to microbial life refers to an organic rich crust which is being constantly replenished. The presence of this crust and the replenishment of water (by outgassing from the deeper ice?) would support the above hypothesis!

Second edit: The Skeptics Guide to the Universe has stated that the original scientific research the above article was based on doesn’t actually make any claim to the existence of life on the comet. It just goes to show that one should always read the original science before commenting, as science journalism does get it wrong from time to time!