Monday, December 29, 2008

Reusing the Skycrane design

One downside to news readers for blogs is that it really cuts down on user posted comments. I received the following from Ken today with some questions on reusing the Mars Science Laboratory Skycrane landing system. With Ken's permission, I'm posting his e-mail and my response.

Blogs and blogs have talked about the US’ one shot deals in missions…. There upside and downside and the long prep time to get one launched… obviously budget has something to do with it. And that is where my idea comes into play. Although still not proven…… we are spending a lot of money on it….. so it better work….. what about participating with other countries on future missions by either offering… or better yet, selling the Sky Crane idea? Yes, it has to work first, but we all know the risk in space exploration. I know there is some intl law for this…. But come on!!!

It just seems we always have to re-invent the wheel (with the exception of the landing bags concept for Pathfinder and MER), but lets use our ideas to help mankind explore. If, indeed, we want to continue to lead in the exploration of outer space, that can be done by helping another country get there. ExoMars comes to mind as a perfect oppty to participate. With their recent delays, this gives them more time to adapt the Sky Crane as its landing option instead of airbags. We get to do another mission of this scope instead of waiting another 12 years…..lets face it, MSL will not happen before then…. And we could recoup some money lost in past budget overrides. Now, we put some cameras on the Sky Crane and we get some extra photos at a great perspective.

Again, after reading your blogs, you may know if there is even a breath of this concept going around. Or maybe once again we just let NASA continue these one shot wonders… I mean there has not been any talk of a Sky Crane 2 for another mission.

My reply:

Ken -

You have some good ideas here that follow some of mine. A few thoughts:

1) The Skycrane is a very novel idea for landing on Mars. One big problem with landing a rover is how do you get it off the lander? Ramps were used for the MERs, but they rested on a minimal platform enabled by an airbag landing. MSL is too large (as I understand it) for an airbag landing system. So, if you have a powered lander like Phoenix, how do you build a practical set of ramps (you need several in case a boulder or other feature makes one unusable). The Skycrane eliminates that problem. It's too difficult to quickly describe, so here are some links: MSL website,, and on-going discussion at the Unmanned Spaceflight forum.

2) Right now, NASA's ideas for the next rover mission appear to be just that -- ideas. Preliminary thinking is to use either airbags or the skycrane. Also tied into this is how much to reuse the entire MSL entry and descent system since it allows much more precise targeting of the landing site. This opens up much more Martian terrain to exploration. It is much easier to find a small safe landing location (near some very interesting geologic formations that are not safe landing zones) than a large one.

3) NASA and ESA have said that they will jointly work on a 2016 rover, but nothing has been publicly said about how. One statement from an ESA official is that they want to develop their own expertise in entry and landing. To me, this is not an optimal solution to making the most of tight budgets on both sides of the Atlantic. I think that a superb sharing of expenses and expertise would be for NASA to supply a modified MSL entry and landing system and share its knowledge of the wheel system (a lot of work has been done to optimize that!). ESA would build the rover. NASA would supply data communications either through the (then) old MRO or preferably through a new orbiter, the Mars Science Orbiter. Either NASA or ESA could provide the launch, although my understanding of US technology export laws suggest that it would be legally simpler for NASA to provide the launch (our technology never needs to leave the US).

No comments:

Post a Comment