As New Horizons reaches the end of the solar system, a Santa Cruz scientist says its findings are full of surprises
Francis Nimmo is the spaciest guy in Santa Cruz, at least for the past few weeks. As one of an elite group of researchers working on the first satellite to visit Pluto and the solar system beyond, the UCSC astronomer has been James T. Kirk-like, exploring strange new worlds and boldly going where no one has gone before.
It’s taken nine years and $722 million for the piano-sized New Horizons satellite to travel three billion miles to Pluto, and Nimmo, now stationed in a Maryland command center, was one of the first to see the photos it sent back when it reached the closest point on July 14. Now, it will travel out of our solar system.
Born in England and schooled at Cambridge University as a geologist, Nimmo, 44, became interested in the heavens after hearing a lecture about space exploration from an American professor who talked about studying Venus. It inspired him to do a project on Venus and study planetary geology. He’s taught planetary sciences, including what the planets are made of and their atmospheres, at UCSC for the past decade. Nimmo’s main job on the project is to determine the size of Pluto and its moon Charon, as well as whether they are perfect spheres.
So far, only two percent of the data from the probe has been analyzed, but Nimmo says the results have been worth the effort. His team spends long days looking at data, meeting in the mornings and analyzing photos and math long into the night. GT caught up with him by phone this week.
How do you feel right now?
NIMMO: It’s kind of overwhelming [laughs]. We’re seeing all this stuff, very little of which we understand, and so we’re trying to piece together the bits of the jigsaw puzzle and make sense of it all. There is so much information that it takes time to assimilate it and get it all into your head.
What’s been the biggest surprise?
To me, Pluto looks much more interesting and much more active than I expected. I expected it to be relatively uninteresting. I expected it to look like Callisto (a Jupiter moon), which is heavily cratered but not very active, whereas Pluto looks like it’s been active quite recently and it has all kinds of features on the surface that we really don’t understand at all right now. There are enormous canyons on Charon that are as big as the Grand Canyon, and Pluto has mountains of ice that are as big as the Rocky Mountains. There are some bits of Pluto that are smooth and look new, so there’s some active geological processes. It’s not a dead world at all. There’s probably some kind of energy source down there and what that means is that one of the things life needs, apart from water, is some kind of energy source. Pluto must be relatively warm, and that’s a good thing for making a habitable environment.
Why is it important to go to Pluto?
One way to think about it is it’s filling in the last bit of unknown on the map of the solar system. Every other appreciable science body we’ve been to, but nobody had any idea of what Pluto looked like. It was a pixel in the Hubble telescope. Now, it’s a world. We’re starting to understand it on a level that we understand all the other bodies in the solar system.
What’s the biggest difference between Pluto and the other bodies?
Pluto is half ice and half rock. There are other places like that, such as the moons of Saturn, Jupiter and Uranus. The big difference is that other moons are orbiting something much bigger than themselves so they get affected by the tides of the big body they are orbiting. Those tides can cause heating and fracturing. Pluto is not orbiting anything big, and so, in a sense, it’s a controlled experiment. What does an icy body look like with no tides acting?
When you get to the far reaches of the solar system, does it make you think there has to be more life out there?
As a general statement, there are two things that have changed since I was in high school. The first huge change is that we now know there are planets everywhere. When I was in high school 30 years ago, we didn’t actually know there were planets anywhere except this solar system. Now we know they are everywhere. The other big change is that there are oceans on many, many of these icy moons. And that’s a big change, because it means that liquid water is far more common in the solar system than we had expected. It’s not just found in this narrow band of the Earth, and liquid water is thought to be one of the prerequisites for having life.
Does that mean the odds are better of more life in the universe?
I think there’s got to be life somewhere in the universe. At this point, with so many other planets, I can’t imagine that there isn’t life somewhere. Now, whether it’s detectable, that’s another question. There’s a big difference between life, which might mean algae, or life like us. So, saying there’s life out there is a weak statement. Saying there’s intelligent life is much stronger. Finding something like algae out there is impossible with today’s technology, but in 20 years we may have the tools to see something like chlorophyll.
And what about intelligent life?
That’s a much harder thing to think about. How long does intelligent life survive, right? If civilizations only last a few hundred years before they destroy themselves, then, maybe it’s not out there. That’s a very hard calculation to make.
Star Trek or Star Wars?
For me, Star Wars, because I was at an impressionable age when it came out. It was the second movie I ever saw, and frankly I don’t think I’ve seen a movie that’s as good since.
How is it that we can get data from Pluto, but I can’t make a call from the beach in Santa Cruz?
Yes, right. The disparity is that you are not carrying around a 200-foot diameter aerial on your cell phone. That’s what’s listening in to New Horizons. It’s a 200-foot diameter dish, so it can collect a lot of signals.
If you had a chance to go on a space shuttle, would you?
Absolutely. And, you know, if somebody offered me a one-way trip to Mars, I would take that, too.
Seriously? Do you have a family?
I do have a family, so maybe I really wouldn’t. Things change when you have a family. But it would be way cool.
PHOTO: NEW HORIZONS UCSC professor Francis Nimmo says he would take a one-way trip to Mars if it were offered. Well, maybe. COURTESY OF FRANCIS NIMMO