Steinn reports that the NRC has made its recommendations for NASA's Beyond Einstein program. The winners appear to be LISA, a gravity wave observatory, and JDEM, a competition of dark energy focussed satellites. Steinn has lots of links to the various projects. The executive summary of the report is availabe here (pdf).
I know next to nothing about these things, but from afar it always seemed like LISA was one of those neat ideas that was never actually going to happen. The basic idea is to put three satellites in orbit around the sun and bounce lasers around to measure gravitational waves. To keep things stable, as I understand it, the lasers would be inside the satellites, but not actually attached to them. Not cheap, but it could possibly open up an entirely new spectrum with which to do astronomy. But, as I said, I know nothing of the politics or technical details, so hopefully some astronomer/astrophysicist can write something up.
Update: Sean weighs in.
It would help immensely if LIGO would see a signal one of these days...
(I'm not dead, just immersed in lab mini-disasters. There should be a couple more posts before Chad returns...)
My understanding is that LISA was the one thing that was going to happen, because the ESA was likely to drive it even if we didn't.
LISA is likely to happen. LISA is kind of the perfect storm of NASA projections. It is hard, expensive and scientifically interesting. The money is big enough to keep some contractors happy, but the project is hard enough to make the money flow for a long time. It will have lots of support from the community, which will give NASA a reason to keep funding it.
Apparently the NRC committee tallied the number of likely Nobel prizes for each satellite, LISA lead at 3. The committee was a bit skeptical that LIGO would ever see anything.
My gut reaction to LISA has always been "Wow. That'll never work."
One expects LISA, as with Gravity Probe B, to succumb to minutia. Fat solar flare, unexpected mass swishing by, hard radiation... or an unanticipated, unexplained, unpreventable ground anomaly,
NOAA N-Prime satellite slipped off its turnover cart because 24 bolts were missing, 06 September 2003. TWENTY FOUR HUGE BOLTS!
Technicians were *not* required to verify bolts were there. Nobody spoke up given discharge for cause/insubordination. Everything went by the book, including gravity (Principia).