Wednesday, August 28, 2013



Based on a plan instigated by Obama, there will be a US Asteroid mission. Granted in 2016 there is OSIRIS-Rex, an unmanned probe of sorts who is to collect samples from an asteroid and return to Earth – sometime in 2018. However, at the moment, NASA’s other main objective is to devise a plan, to come up with options and evaluate a plan to bring an asteroid to a lunar orbit. The basic outline proposed so far is to have the SLS lift a robotic Asteroid Redirect Vehicle into orbit in the year 2025 then make a trip to an asteroid using an ion propulsion system.

You may recall the discussion on this blog about ion propulsion and how inefficient it is when utilized by a manned spacecraft. Very low thrust, actually it doesn’t produce its own power – an external power source is needed. Additionally it would have a de-acceleration phase as it came close to its target which means it would require an additional source of energy – maybe Nuclear Fusion? VASIMIR? OR NASA does already have a great system  NEXT, which utilizes thehuge solar panels needed or a nuclear battery. (They ran it nonstop for five and a half years as part of a test!)Unmanned probes are already successfully using ion propulsion. Deep Space 1 was the first and the DAWN probe which has been tasked with the exploration of Vesta & Ceres (2 massive objects in the asteroid belt). Ion propulsion while certainly having its disadvantages is consistent and long running.

After the propulsion drive gets there, that’s the interesting part. The plan states that the vehicle would surround the asteroid with a huge inflatable cylinder. (Sounds like a job for Bigelow Aerospace?) Once secured, the cylinder would pull tight, cinching the asteroid and uponhaving been de-spun it would be re-directed to its new home in the lunar orbit. Once there, astronauts on the Orion would dock with the redirect vehicle, go to the asteroid via a boom type device then using the numerous metal rings around asteroid to secure themselves, cutthe Kevlar like cloth that envelops it and proceed to take samples and otherwise spend about six days doing the balance of the mission before returning to Earth.

Interesting. So then the mission is to understand more about an asteroid before one slams into us. Always good to know thine enemy

There is also the space elevator. There is a need for carbon for the tether. The biggest problem WAS forming a Carbon Nanotube Ribbon, but there is a group at Rice University this year that says they are able to form it and there were advances by another group as well, so this may be the dominos falling to say the technology is there. Next up, we will need to gather the carbon, and also we need to discuss the politics. There should be a joint venture – between at the very least the ESA and the US. Maybe Canada, and other ISS partners? It’s a pricey item (~10 billions)with the ability to open up the skies! From enabling more frequent space travel, to dropping satellites, perhaps to having tourists invade space hotels. Remember just one launch for satellites or other reasons costs from $400 million to $800 million so we would be able to pay for the cost of it in 10-20 uses. Unprecedented turn-around time in launches. (Bring the price down, no reason to wait!) For those who whine about forget space, what about earth – the costs of putting up a satellite plus the cost of an advanced piece of communications or otherwise satellite does get passed on to you. Between the Space Elevator bringing the cost to put it up down and the RRM making it last longer before needing to be replaced, the Space Elevator is for Earth!

I know you are tired of hearing it, but I tell you again – NASA never does just one thing. Every mission seems to satisfy three or four needs and maybe a hope or two. Mission, capture an asteroid. Mission, success!

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