We’re going to get better and better at characterizing planets around other stars. That’s going to be a big thing. We’re going to start to find smaller planets, Earth-like planets. I think—I’ll make a prediction here—we’re going to start to realize that Earth-like planets are relatively common and this will feed into the whole idea of, is there life on other planets out there? We’re going to learn to detect remotely any signs of life—if it’s an oxygen-rich atmosphere, or if it’s some other atmospheric signature, or maybe it’s something you can see, changes on the surfaces or something like that. I think we’re going to really start to get better and better at characterizing and detecting extra-solar planets. That expands our number of targets from nine, keeping Pluto as a planet, to hundreds and thousands of objects in nearby space to us. Planetary science is going to blossom enormously because there’s simply that many more planets out there that need to be studied.
I think the fact that the field has grown so much is because there’s so much excitement in it right now. It’s not just our solar system, either; it’s the discovery of planets in other solar systems. The big growth areas I see are extra-solar planets, which are now a really hot topic; and I also see astrobiology. It’s growing in fits and starts, but ultimately there are really interesting constraints that planetary science provides for life and vice versa. I think that will be another big growth area as we become more sophisticated.
Scientifically, the lab is getting more and more interested in extra-solar planets. Exobiology, astrobiology, things like habitability—you can have a discipline in astrobiology even if you don’t find any extraterrestrial life. Stephen Gould called it “that great discipline in search of its first data point.”
I think since the discovery of extra-solar planets, planetary system formation has gotten to be more respectable astronomy. We now have a lot more bridges with the Steward Observatory. There’s a group there that works on planet formation and collaborates very closely with LPL. That old separation is being healed over.
It’s a joy to see each of these worlds turn into a place that you can get really familiar with, intimate with. But the nature of science is changing for each of those worlds; the obligation of how much you have to explain is correspondingly higher. I do see us turning more and more worlds from complete unknowns into well-categorized places, but the fact that we’ve found planets around other stars means that we’ve got a good set of fuzzy points of light that we have yet to explain. I find extra-solar planets a true growth field for planetary science.