Being a principal investigator on Cassini and knowing about all of the discoveries there, I have to say that investigation of [Saturn’s moon] Titan in detail is really an intriguing possibility. The discovery by Cassini of these lakes and rivers of methane at minus 182 degrees centigrade is just astounding. In addition, there is an inference that there is an underground ocean of liquid water under the crust of Titan. To go and land there, and watch the weather, and float in the lakes and see lightning and other things as they operate in the primitive atmosphere of mostly nitrogen and methane and acetylene—it would be a terrific exploratory mission. And it is possible with today’s technology. I think that’s one big objective.
The other part at Saturn is, of course, the Enceladus geysers that are coming from the south pole, which have all these organic materials with no real understanding of where that organic material is coming from. I think of these two questions just because I’m so intimately involved in the Cassini mission.
But I have to say that now that we know what we know from Voyager, I think the country is missing a big opportunity to really further explore where our solar system is headed into the galaxy. We have been studying for years—by “we” I mean the whole scientific community—what’s called an interstellar probe that would go much faster than Voyager and get into the galaxy and provide data for the next 30-40 years, but unfortunately, the funding isn’t there to do such pioneering missions anymore.
Do you think New Horizons will provide some of that data?
Not really, New Horizons of course will do this exploratory mission of Pluto, and after that we’re going to try to head it to a Kuiper belt object, but it is not as fast as Voyager, simply because in addition to going by Pluto we will also do this KBO flyby. So New Horizons will not have either the communications capability or the speed, even if it lives as long as Voyager. We’re going to have to come up with a brand new mission with new technology and ways to speed it up a lot, maybe by getting the gravitational assist from the sun itself to really move it out at a speed at least three to four times that of Voyager. And I don’t see that happening, unfortunately.
My dream for years had been to do a solar probe, and finally we are doing that here at this laboratory. It’s called Solar Probe Plus. It will get within six million kilometers of the sun after we launch in 2018. So we’re making progress—we have a mission to a star!