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 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.
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.
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.
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.
Unless you’ve been sleeping under a rock you’ve no doubt seen the announcement by NASA today that water has been discovered on Mars (sort of, but we’ll get to that in a moment). After a day of sensational hype created from NASA’s pre-warning of an important press release, this was making headlines from the word go, with everyone speculating on the topic of discussion. The discovery of aliens, mysterious artefacts and water on Mars were all proposed.
Here is one of the images which helped make the discovery. Images of the same part of Mars’ surface at different times shows these streaks appearing between shots, indicating an active landscape. The dark streaks are on the order of 5 metres wide, often narrower, were first discovered over a decade ago, and have been called ‘recurring slope lineae’. There were numerous proposed causes for these, including water, but also avalanches or grains of material rolling down slopes.
Once the CHRISM spectrometer was applied to these streaks, the spectral signature of the features could be analysed, revealing their composition. Hydrated salts were found on every streak, but were strikingly absent from the surrounding surface. Water turns to liquid on Mars’ surface at 0 degrees Celsius, just as it does on Earth, but water with a high concentration of salts will melt at much lower temperatures (try this at home with some table salt!). The flows appear when temperatures rise over -23 degrees Celcius, which is reached during the warm season in parts of Mars.
Researchers are working on determining where this water has come from. Possible theories include porous rocks under the surface and saline aquifers existing in some areas below the surface in areas. Alfred McEwen, a planetary geologist, prefers the theory that the salts exist on the surface of Mars, and absorb water from the atmosphere until they reach a point where they have enough liquid to flow downhill, a process known as deliquescence. To me this would indicate that the surface of Mars where these features form would be laden in salts, but as mentioned earlier the spectral imagery does not seem to support this theory.
So why sort of? To be precise, we haven’t directly detected water flowing on Mars, only signs (however promising) that point towards water flow. But we must always be cautious and consider other processes that may create the same results (or even processes we have never encountered before!).
“Does this mean life on Mars?” everyone cries. The presence of liquid water (however transient in this case) is a good sign for the existence of life. Dr Grunsfeld of NASA has stated that “If I were a microbe on Mars, I would probably not live near one of these [sites]”. He suggests that underneath a freshwater glacier, such as those suspected in the north and south, would yield more ideal conditions for life.
In any case, these are certainly exciting times for Mars exploration. Of course, a ground-truthing experiment (physically checking these sites, drilling and collecting samples) would prove this theory right or wrong. Here’s to hoping we can get a geologist to these sites soon! If anyone asks, pick me.
Hey space lovers! I’ve recently signed up to be a member of The Planetary Society and if you should too if you aren’t already. Not only do you get an excellent t-shirt (see below) and a quarterly issue of The Planetary Report magazine, you are funding space advocacy and adding your name to an important body that will promote space exploration.
Have you ever wondered why comet 67P looks the way it does? It’s a strange shape and looks a little like 2 bodies that have been fused together, but to the researcher’s surprise, the cometary activity appears to originate in the neck. Why? Rapid temperature change in the neck, causing cracks and inducing volatile loss. Check out Emily Lakdawalla’s blog entry for the full spiel!
Today I was reading an article by Frank Stratford, CEO and founder of MarsDrive, about the benefits of going to Mars. I was nodding my head in agreement as I usually do, but after looking at the comments, one by Heinrich Monroe particularly threw me. It’s a long one, so I’ve picked out the key points (in my opinion).
“Oh, we’re going to get spinoffs from it? Like “from medical technology to food and water to new materials, safety technologies, and so much more”? … You know, if we spend $100B on just about any massive technological and engineering goal, spinoffs like that… will fall out as well. The question is whether those spinoffs were really worth $100B, and whether we couldn’t have gotten more value on them with smarter investment.” – Heinrich Monroe
When I talk about the value of having space science programs, in addition to the intrinsic value of advancing scientific understanding, I often refer to the unforeseen advances in technology that come as a result. For example, we probably wouldn’t have instant global communications via satellite feed, let alone the host of material science, medical and software advances that have resulted from space programs. But the comments made by Heinrich did make me wonder whether we could have achieved these better with direct, targeted programs.
As Donald Rumsfeld has said, there are known knowns, known unknowns and and unknown unknowns. We don’t even know about some of the discoveries to be made working on space science and their implications to every day life until we make the discovery. However, one could perhaps say the same about a targeted research program. It’s certainly a tricky one to answer, although I will say this.
There is a lot of money being used for things that I disagree with ethically, and that isn’t being used for programs such as advancing medical science. By advocating for more space science funding, I’m not convinced that this would greatly cannibalise funding going towards these other programs. It’s not a choice between one or the other.
Having said that, I would be very interested to see a study that estimates the value of space science research compared to direct research in other fields. This is presumably very difficult, as it’s hard to put a number on the value of science development (would discovering life on Mars have intrinsic value?), but this shouldn’t stop people from trying. I’m sure something like this exists, but given my experience in determining the effectiveness of charities, I wouldn’t be that surprised if it didn’t. One example is the fact that for every dollar invested in NASA, there has been a $7-14 return on investment. If you are aware of any general studies of this nature, feel free to put a link in the comments below.
I may be biased – I am a space science researcher after all!
Here is a link to a neat infographic that summarises the spin-off benefits of NASA technology and funding.
Hey everyone. I’m in central Australia working on a seismic survey crew at the moment so my blogs will become a little less frequent, but luckily I still have (limited) internet connection so I can still post!
I just finished watching Europa Report, which was, overall, quite entertaining. Without giving away too much just yet, it’s a movie about the first human mission beyond the moon. A crew of 6 are sent to test whether life exists on the or under the icy surface of one of Jupiter’s moons, Europa.
A tale of human sacrifice, one of the more memorable quotes was “Compared to the breadth of knowledge yet to be known, what does your life actually matter?” I too have wondered this, and as a scientist I easily sympathise with the sentiment. I would gladly lay down my life for science, and often wonder what I would do and sacrifice in the face of overwhelming odds if I were chosen for a manned Mars mission (I think it’s likely Mars will happen before Europa!).
I definitely appreciated the cameo appearance of Neil deGrasse Tyson talking about a mission to Europa, even if not originally filmed for the movie.
Despite this moving quote and underlying theme, there were just far too many scientific flaws for me to ignore. I’m used to seeing unrealistic technology in sci-fi movies, but not blatant breaking of the laws of physics.
— SPOILER ALERT —
First, the crew were maintaining near instantaneous communication with their control centre on Earth for much of the mission. As far as several months into the journey, near Mars, there did not seem to be any delay in voice. Light takes as little as 4 minutes to travel from Earth to Mars (then 4 minutes back) and as much as 24 minutes. Even at the Moon the delay would be about 1 second either way. But that’s ok, maybe humanity in this near-future society has found a way to achieve faster than light communication.
Once the crew landed on Europa, I was looking forward to seeing the crew float around in the low gravity. Europa does have the mass of about 0.008 Earths after all, giving a gravity of 1.3 m/s/s, slightly lower than our own moon’s. Nope. They were stomping about and lugging equipment like they were being accelerated at a casual 9.8 m/s/s.
Speaking of landing on Europa, why did they need to send five crew members to the surface anyway? Why did they need to send anyone down? Surely the whole sample collection mission could have been done with robotics. But then if that’s the case, why send humans to Europa in the first place? The only benefit would be that humans could have a quicker response time to tweak the robotics and react to problems. But even that seems like an unduly large risk.
Last, the crew, especially the science team, spent way too much dialogue talking about how they were going to run tests or analysis on data they had just acquired (Which yielded ground breaking results in seconds. So much for data quality control!). Groan. People look at me strange when I start saying that in a lab!
Besides all that it was an enjoyable 90 minutes! But I wouldn’t watch it again. 7/10.
The title of this article might sound provocative and reminiscent of Interstellar, but it’s much simpler than that. Apparently.
Today I’m summarising the paper published in Acta Astronautica by Patrick Collins and Adriano Autino (full reference and link at end of article).
The authors argue for the development of an industry based around passenger space travel, arguing that is could be economically and socially very beneficial. It would create a use for half a century of technological development and sharply reducing the cost of space travel by creating economies of scale, making other activities in space cheaper and even profitable. The paper rather boldly finishes the abstract with the following statement:
“The paper discusses the scope for new employment, stimulating economic growth, reducing environmental damage, sustaining education particularly in the sciences, stimulating cultural growth, and preserving peace by eliminating any need for “resource wars”.”
Wow, all that just by creating a space tourism industry? Let’s back up for a moment.
The authors argue that if German rocket development continued as it had at the time of 1942 when they achieved first successful spaceflight, fully reusable sub-orbital passenger flights could have been feasible using reusable, piloted spaceplanes by 1950. Under this scenario, passenger travel services to and from low Earth Orbit would have been feasible by the 1960s. Instead, rocket development was primarily focused on producing thousands of long-range missiles during the cold war.
Because of this, launch vehicles were based on rockets, rather than passenger vehicles as aircraft had been. This focus meant that launch vehicles had safety and cost/passenger more aligned with missiles than passenger vehicles.
Slightly related, check out this video compilation of early rocket failures I’ve been itching for an excuse to share.
The mobile phone is used as an example of faster than predicted uptake of a new technology, and the argument seems to be that therefore space tourism and travel will take off faster than expected. But not all technology works like that (one only need look at the Segway for a technology that went in the opposite direction).
It is argued that even a small government investment into the personal spaceflight industry would yield high returns, and with investments of around 1% of what governments give to space agencies. This is “utterly negligible compared to the trillions that they have given to banks during 2008-9.”
“Starting from today, in order to achieve the scale of activity shown in Fig. 1 over the next 30 years, government funding [required is] equivalent to about 10% of space agencies’ budgets, or some € 2 billion per year… Thereafter most of the funding would come from private companies, just as airline and hotel companies finance their own growth today.” I’m always suspicious of anyone who says ‘It wouldn’t cost that much money to fund, and the benefits are huge!’ If that were the case, there must be good reasons governments aren’t doing this already. Sure there are vested interests, which is partly why it has taken so long for governments to get on board with renewable energy, but there must be some reason.
Cost estimates from several sources indicate that once the space travel industry grows to 1 million passengers/year (no small figure!) prices could fall to € 5000 for sub-orbital flights and € 20,000 for orbital flights. Much cheaper than it is now, to be sure, but I still wouldn’t be signing up for leisure trips at these prices. Sure, some will, but I wonder if it will still be the domain of millionaires who have a bit too much money on their hands. And if so, how will the industry grow to 1 million passengers/year?
Don’t get me wrong, this would all be great, and as the authors say, “orbiting hotels seem likely to create the first market for non-terrestrial materials like ice, water, oxygen and hydrogen…”, which, as an asteroid mining researcher, sounds pretty good to me. I’m just sceptical and playing devil’s advocate a little.
I’ll skip over the employment and economic growth sections to get to the areas I’m more familiar with. “Economic development in space… could contribute greatly… to solving world environmental problems.” This is proposed through a space-based solar power (SSP) supply (which would become much cheaper with lower space travel costs) and carbon-neutral space travel (utilising the SSP).
“The use of solar power satellites for reducing the severity of hurricanes… In the extreme case… SSP might even include a role in the stabilisation of climate.” I haven’t heard this form of geoengineering proposed for Earth (similar ideas are proposed to terraform Mars, see my article here), but it seems awfully reminiscent of spraying particulate matter into the atmosphere to reflect sunlight and other extreme geoengineering solutions to climate change for 2 reasons. One, we don’t know what the potential negative implications are, and two, these types of solutions should really be a last resort in case we can’t get our shit together and mitigate climate change by just reducing greenhouse gas emissions. I’ve heard it argued that having geoengineering solutions as a backup may make people and policy less motivated to act now to stop climate change.
There is something to be said for having more humans look at our planet from a new perspective. One of my favourite quotes is by astronaut Edgar Mitchell who said “From out there on the moon, international politics look so petty. You want to grab a politician by the scruff of the neck and drag him a quarter of a million miles out and say, ‘Look at that, you son of a bitch.’”
The authors also argue that having a space based economy would eventually mean that more of Earth’s industry would operate outside the biosphere. I’m not so convinced that there would be enough industry in the near term for that to make a difference, and surely an expanding space economy would equal an expanding ground-based economy.
Flying past education, more space travel means more young people fascinated by science, technology and engineering, yes of course… Culture benefits… Ah, world peace and preservation of human civilisation.
“The major source of social friction, including international friction, has surely always been unequal access to resources.” The argument is that if we expanded into space and tapped into the vast resources available there, we wouldn’t need to have ‘resource wars’ on Earth. I’m iffy about that. It’s a nice idea, and would most likely reduce wars, but even if everyone had equal access to resources, someone would want more than their equal share.
The final argument is that having a thriving space economy not just around Earth, but on the moon, on Mars and even beyond would reduce the chance that humanity is wiped out by a single catastrophic event. I agree with this completely, and this is what Elon Musk is working towards with his plans to colonise Mars. Given the vast potential future number of human lives, it would be selfish to not try to reduce existential risk. Neil Bowerman from the UK who I met recently in Melbourne is working on various forms of existential risk, and his website is worth looking at if you want to read more about that.
I’ve been purposely pessimistic throughout this article, but I truly hope for all of the arguments for a space economy that I’ve mentioned come to fruition. It’s one of the reasons I am a space science researcher; it’s what drives me to work every day.
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.
One of the main arguments for not sending humans to Mars yet is the dangers of interplanetary radiation. Luckily the Earth’s magnetic field protects us and low orbit astronauts from solar radiation, but unfortunately en route to Mars we lose this natural protection.
Metal is not very good at protecting from radiation, so some engineers have suggested surrounding living quarters (or at least one emergency room for high intensity events) with water which is much more effective at blocking radiation. Dr Robert Zubrin has even proposed surrounding a room with a certain human waste product produced mid-flight that happens to contain a high percentage of water. Might as well use it if it’s there! With this level of shielding, the total radiation exposure is expected to be low enough that a 6 months journey would give you a lower increased risk of cancer than regularly smoking.
CERN scientists are producing an experimental magnetic shield technology utilising the same superconducting coils used in the Large Hadron Collider (click here for the full article on IFLS). The end effect would be to deflect incoming particles in a way similar to the Earth’s magnetic field. While this technology has some way to go before being placed on a spaceship, the existence of the above combination of technologies and techniques should by now be sufficient to put to rest at least this one fear of sending humans to Mars.
Hey everyone, just a quick post for today to summarise some stuff I’ve read that I thought was pretty cool.
Apparently the cost of travelling to the Moon can be reduced by a factor of around 10; down to $10 billion US from $100 billion US. Utilising water and hydrogen on the lunar surface as fuel, this can also significantly reduce the cost of travelling elsewhere in the Solar System. This of course flies in the face of Dr. Robert Zubrin’s claim that we don’t need to go back to the Moon to get to Mars. The study says that in 10 to 12 years, a four-person industrial base on the Moon could be built at a cost of $40 billion US. Of course, as the study admits, the fuel resources are not guaranteed, and some kind of exploration would have to be undertaken to prove their existence in quantities large enough to be worth extracting. Check out the summary article here or the report here. The report is a long read and I’m still working my way through it; I’ll put up my own summary when I’ve finished.
This article by Tanya Harrison explains how some of the cool surface features at Mars’ south pole formed, and tell you how YOU can help map Mars! Click here to check out the Zooniverse project that puts you in the scientists’ chair to pick surface features on imagery taken by the Mars Reconnaissance Orbiter.
So it turns out Pluto is red, and the reason is ‘tholins’. What are tholins? They’re basically complex organic molecules. Find out more about these and the implications here.
Finally, the B612 Foundation is worth looking into if you haven’t already heard of it. Simply put, they aim to enhance our capability to protect Earth from future asteroid impacts which can be potentially catastrophic for our civilisation through science, technology, advocacy and education.
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.
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