Sunday, November 10, 2013

The Threat From Space May Be Much Greater Than We Thought

We have known for some time that Near Earth Objects (NEO) are a serious threat to civilization. We also know, more-or-less, how to reduce that threat significantly at very reasonable cost. We have thought, however, that comets were much less of a threat which is a good thing, as they are much harder to deal with.

Unfortunately, it appears that a large comet may have missed Earth by only a few hundred kilometers in 1883. If the comet fragments "had collided with Earth we would have had 3275 Tunguska events in two days, probably an extinction event" [MIT Review].

We know that comet Comet Shoemaker–Levy 9 struck Jupiter in 1994. Comet C/2013 A1 is currently believed to have a 1-in-8,000 chance of striking Mars in October 2014, passing within 120,000 km. That's close enough to endanger satellites orbiting the Red Planet.

It appears that either we are in a period of unusually frequent close encounters with comets, or cometary threats to our existence are fairly common. Defense against comets is much more difficult than against NEOs. Comets spend most of their lifetime in the far outer portions of the solar system where they are hard to observe, and when they do come through the inner solar system they are usually moving very fast, giving little time to respond even if we detect the threat before a collision.

NASA spends about $20 million/year of NEO detection, most of which pays for ground telescopes. For one percent of NASA's budget ($160 million) we could have an absolutely outstanding NEO detection and deflection program. The immediate need is for an infra-red space telescope to find most of them, for example, the B612 Sentinel. As NEO defense is essential to our survival, it is a little silly, and potentially criminally negligent, that we spend orders of magnitude more money on very interesting, but much less important, projects.

Cometary defense, however, is not cheap. Detecting a cometary threat in time to do something about it requires extremely capable telescopes. Comets are dirty snowballs which tend to break into pieces making them very difficult to deflect. If further analysis finds comets to be a significantly greater threat than currently believed, be prepared to open the checkbook.

Sunday, October 27, 2013

Space Debris, an Interesting Number

"On-orbit, predicted conjunctions vary based on the debris density at the altitude of the vehicle. For altitudes of 350-400 km, approximately 3 maneuvers would need to be made annually." from the FAA's Draft Established Practices for Human Space Flight Occupant Safety.

This gives one an idea of the impact space debris is having right now: an average of three maneuvers per spacecraft per year to avoid collision. As space debris is expected to increase, the costs associated with dealing with space debris will undoubtedly rise. We can also expect the destruction of more operational satellites, which has happened twice so far.

The most dangerous space debris is the thousands of large pieces, mostly Russian upper stages, in polar orbits. When these have collisions, tens of thousands of pieces of debris are created. Indeed, we may be currently in a very slow motion chain reaction of collisions creating debris that in turn creates collisions which create debris ... The debris is moving at very high speeds, so even a small piece can destroy a satellite. The film 'Gravity,' while not particularly accurate technically, highlighted this quite effectively.

What to do: the single easiest and most effective act would be to get rid of the large pieces. It's been estimated that removing 10 per year would be sufficient, statistically, to start reducing the total amount of debris in LEO assuming other activities don't add much. We should get started on serious debris reduction. Otherwise, given enough time we could easily pollute Earth orbits with enough debris to end the space age.

Sunday, October 20, 2013

Launching Commercial Space Enterprises Workshop

This workshop was put on by CASIS (Center for the Advancement of Science in Space) and the Silicon Valley Space Center 18-20 October, 2013. Highlights (for me) included:

  • CASIS will fly your ISS (International Space Station) payload for free. You can also get free astronaut time. You can even have materials returned to Earth, again, for free. By law, CASIS can give away up to half of the US resources on the ISS. Although CASIS is not allowed to charge for ISS resources, in practice you'll probably pay a small amount for one reason or another. To get (almost) free access to the ISS you can either compete in periodic CASIS calls for proposals or submit an unsolicited proposal. If you don't need power on the trip up or back there are ample resources right now.
  • Through CASIS you can get ISS Hyperspectral Imager for the Coastal Ocean images for free. They aren't on the web, but you can make requests. You can also ask that the instrument look at specific locations.
  • CASIS has a small amount of money (about $3 million a year right now) to fund proposals. Not only can you fly for free, you can even get paid!
  • Made In Space will be flying a 3D printer on the ISS in the next year or so. It will be able to print objects up to the size of a cubesat (10x10x10 cm). They are interested in ideas about what to print.
  • BBC Aerospace has a 3d printer for any weldable metal using an electron beam. They say they can make very large objects. Currently they can produce 20 lb/hour and expect to double that soon.
  • Blue Origin said that they intend to fly a hydrogen/LOX orbital vehicle by 2018. If all goes as planned, this vehicle will have a reusable first stage! They also mentioned a recent study that found a market for about 500 sub-orbital seats per year, 80% filled by tourists.
  • S3 received $250 million from private investors to develop a launcher based on a half sized version of the European reusable Hermes space plane design. The first stage is an Airbus (a commercial jetliner) which carries the space plane to 40,000 ft or so. The space plane gets up to space altitudes (100km or so) and returns for an airplane-like landing. It can carry an upper stage that will get small sats into orbit. Alternately, it could carry sub-orbital tourists. However, their target market is point-to-point high speed human transportation. They are creating a presence world-wide that they hope to develop into destinations for very fast intercontinental transportation.
  • DragonLab, which is a Dragon capsule flight on a Falcon 9, costs $100 million/flight with a maximum of 2,175 kg of returnable pressurized cargo, a maximum of 3,310 kg of unpressurized cargo (which won't return) with a cap on total payload of 3,310 kg to an ISS-like orbit. You can probably get more mass to a lower inclination orbit. For ISS inclinations, that works out to about $30,000/kg.
  • Zero Gravity Solutions presented their work on the ISS showing that micro-g strongly affects gene expression. They believe they have ways of manipulating that expression to improve plant species without genetic modification, just turning on and off genes that are already there. One target is a plant that grows in the tropics and produces jet fuel. They are working on modifying gene expression of this plant so that it can grow in colder climates; for example, Texas.

  • There is quite a lot of protein crystalography work on the ISS.
  • There are a number of small companies that offer bundling of launch services. The idea is to do the paperwork and other mundane tasks associated with launching a payload to allow the customer to focus on the spaceflight itself.
  • Alan Gassan presented some software that predicts exactly what the ISS can see on the ground depending on time. This is being used by the astronauts to take photos. There is also a crowd-sourcing app to register the images to the ground (the place is known by the time stamp on the photos but not the orientation of the camera).
  • I had a couple of not-very-well-formed thoughts while there:

  • One could use Gassan's system combined with the programmable communication testing equipment already onboard to test space solar power related energy transmission. Gassan's system would tell you when power can be transferred to ground receivers.
  • There might be an educational market for cubesats with hardware to grow plants. Hardware would include LED lights, camera, nutrient and water delivery and an API to command it. Sensors for temperature, atmospheric water content and so on would be good too. Such a cubesat has been flown, but the idea here is to make it easy for students to fly different seeds. A major problem is delivering enough water over a long enough period to get more than seedlings before the water runs out.

    I attended the conference hoping to find new killer apps for space settlement, something other than tourism and space solar power. I didn't find any, but I did see a lot of small-step progress in many directions all heading toward the commercialization and industrialization of near-earth space which, in turn, is probably essential to building the first free-space settlements. See Paths to Space Settlement.

  • Sunday, August 11, 2013

    If you like Space Settlement, go see Elysium!

    I saw the new sci-fi movie Elysium with Matt Damon and Jodie Foster a couple nights ago. First, it's a good movie, not a great movie, but a good movie that held my interest, made me care about the characters, had a good message, and included a goodly bit of drama, humor, and excitement. Three days later I'm still seeing scenes in my head, a good sign.

    Elysium is set in a world with an over-populated, dirt-poor Earth and a wealthy, beautiful, wonderful and extremely large free-space settlement in Low Earth Orbit called, you guessed it, Elysium. The movie answers one of the great questions of space settlement: why would anyone want to live in space? Because it can be a really great place to live. There's another important pro-space settlement message but I don't want to spoil anything, so I won't tell you what it is.

    Some in the space movement have criticized Elysium because, among other things, it is a haves vs. have nots movie and they don't like such things. To me, that's like complaining that dogs bark. It's a movie, and this is one of the standard stories of the entertainment business (going back, at least, to Cinderella). Other's complain about technical inaccuracies, of which there are plenty. To which I say, it's a movie, folks, not an engineering project!

    So if you want to see a beautiful depiction of exactly how great living in space could be, and have a good two hours of entertainment to boot, go see Elysium!

    Friday, April 5, 2013

    A Gutsy Asteroid Move!

    "NASA's fiscal 2014 budget request will include $100 million for a new mission to find a small asteroid, capture it with a robotic spacecraft, and bring it into range of human explorers somewhere in the vicinity of the Moon," according to Aviation Week and Space Technology. For more detail on the concept behind this mission see A Comparison of Astronaut Near-Earth Object Missions by the Asteroid Mining Group (including yours truly) and/or the more detailed Asteroid Retrieval Feasibility Study by the Keck Institute at JPL.

    If successful, I believe this is a game-changing mission. There would be roughly 500 tons of asteroid safely stored in a convenient, easy-to-get-to orbit. It is reasonable to expect that the government would lease mining rights, which is done all the time with federal lands on Earth, at little or no cost. Thus, one of the hardest parts of space mining would be accomplished, the first delivery of large amounts of extra-terrestrial material much closer to potential customers (i.e., people on Earth and the satellite industry). The asteroid mining industry would get a huge lift not only from the materials delivered, but the fact that a second (or third or ...) delivery would cost much less.

    Furthermore, put enough of these missions together and you have the materials to build the first space settlement in Earth orbit! Admittedly, this would requie a lot of missions and/or returning larger asteroids. Still, this mission would be a significant step on one of the Paths to Space Settlement, my vision of the most effective approach to space settlement.

    If you think this mission has merit, consider contacting your elected representatives.

    Saturday, March 2, 2013

    A Small Step Toward Space Hotels

    On January 11, NASA announced a $17.8 million contract with Bigelow Aerospace to provide an inflatable BEAM module to attach to the ISS in 2015.

    The eighth ISS SpaceX Dragon flight is expected to deliver the module in 2015, and it should stay at least two years before being released and sent to burn up in the atmosphere. Interior pressure, temperature and radiation levels will be monitored and compared to conventional rigid modules. Folded up, the BEAM can ride within the “trunk” section behind the SpaceX Dragon capsule. The BEAM is 4m long and 3.2m in diameter when inflated. That’s slightly shorter and a somewhat wider than the two Genesis modules currently in orbit.

    This is a nice step on the way to a private space hotel!

    BTW: current prices for Bigelow's to their in-work Alpha station, consisting of two BA-330 modules are:

  • Astronaut flights: $26.25 million/seat via Dragon/Falcon 9
  • Leasing volume: 1/3 of a BA-330 (110 cubic meters) for $25 million for 60 days, which works out to $150 million for the whole facility.

    This would work nicely for a Space Olympics! See a space olympics educational proposal

    Space hotels are, of course, part of one of the Paths to Space Settlement.

  • Friday, February 15, 2013

    We Just Got a Warning Shot, More Coming

    This morning a small asteroid streaked through the Russian sky and exploded, breaking windows, damaging buildings, and injuring about 1,000 people, 40-50 of whom needed hospitalization. See the New York Times article. There have been at least three other hits like this in the past few years.

    Here's some of my favorite videos of today's hit:

    There is a truth that needs to be told: there are thousands of much larger asteroids out there that will hit us, we just don't know when. Before the next big one hits, we need to find it and deflect it. Finding and deflecting asteroids is not particularly expensive as space projects go, but the current NASA funding is pathetic, about $5 million/year (in a $17,000 million budget). We have to find these killers some day, why wait and risk disaster? Why not do it now?

    If you want to help, consider donating to the B612 Foundation Sentinel Space Telescope. If successful this project will find 100 times more potentially dangerous asteroids than we have found so far (about 10,000). Once we find the next good sized incoming asteroid, funding for a deflection mission should be easy to come by :-)

    To see how this relates to space settlement, see Paths to Space Settlement, Al Globus, NSS Space Settlement Journal November 2012.