Kudos to NASA for launching code.nasa.gov, where NASA will try to nurture some of the space-related open source projects in its, ahem, orbit.
In 2005, I was briefly involved in some efforts to create a code hub within NASA, but balked when I read the NASA Open Source Agreement and NASA appeared unable the modify it. The license is fatally flawed. Here’s what FSF says about it:
The NASA Open Source Agreement, version 1.3, is not a free software license because it includes a provision requiring changes to be your "original creation". Free software development depends on combining code from third parties, and the NASA license doesn't permit this. We urge you not to use this license. In addition, if you are a United States citizen, please write to NASA and call for the use of a truly free software license.
That’s quite the right position on this license, which is to say if you are choosing a license for your project, please don’t choose NOSA. You’re probably better off with something more permissive (i.e. something that can be turned into NOSA if needed).
NOSA is also not a general license, although my initial 2005 look at the world of NOSA-licensed code turned up a lot of stuff using it as such. If you are going to release a new project under NOSA and you are not a Government Agency, things can get murky. Best to avoid NOSA when you can.