One important concept in the grade 12 Physics unit of “Energy and Momentum” is the conservation of energy

Are we alone? Earth-like planet fuels curiosity about space By Barbara Aggerholm, Record staff

WATERLOO — At a New Year’s Eve party, astrophysicist Michel Fich wasn’t surprised when the conversation turned to planets outside our solar system.

One month earlier, NASA scientists announced they had discovered a planet outside our solar system, now called Kepler-22b, and that it seemed similar to Earth in many important ways.

“This is a major milestone on the road to finding Earth’s twin,” Douglas Hudgins, Kepler program scientist at NASA’s Washington headquarters, said in a statement.

The discovery has fuelled imaginations and raised again an age-old question explored in countless science fiction movies and books: Are we alone?

Fich, a University of Waterloo professor in the department of physics and astronomy, is a well-respected scientist currently working at the centre of three astronomical projects with international partners.

He leads a Canadian team collaborating on a superpowerful astronomy camera called SCUBA-2 that is expected to aid major breakthroughs in astronomy, including research on the origins of the universe. The camera, mounted on the James Clerk Maxwell Telescope in Hawaii, was turned on recently and has yielded some “exquisite” data that Fich is itching to talk about. He spent 19 days using the camera in early November.

He’s also the Canadian team leader of the Cerro Chajnantor Atacama Telescope (CCAT), which will be powerful enough to look back billions of years after it’s built in the Chilean mountains.

And he’s a Canadian leader in the European Space Agency’s Herschel Space Observatory. Fich led the Canadian team that developed a complex spectrometer, the only Canadian-built hardware flying on the satellite, which will help scientists study water in our galaxy and beyond.

So it’s natural that fellow guests at a New Year’s Eve party might turn to the personable astrophysicist — he jokingly calls himself a rocket scientist — for answers about Kepler-22b.

Fich doesn’t work on the Kepler space telescope, which made the discovery. But he’s glad to talk about why astronomers are excited about the find.

Scientists say the temperature on the surface of Kepler-22b could be about 22 C. Its star could be almost a twin of Earth’s sun and it probably has water and land. And it was found in the middle of what’s called the “habitable zone,” making it a potential site for life.

“All we know about it is that we know it’s orbital period is 290 days and we know its radius is about two and a half times the radius of the Earth,” Fich says. The rest, he adds, is speculation.

“Kepler-22b is the only planet in that solar system and it’s the only planet anywhere that we’ve ever found that has a strong likelihood of having a liquid water surface, which means it has a possibility of having life,” says Fich, adding that it’s likely a rocky planet.

He doesn’t rule out the possibility of intelligent life existing there, but says it’s not likely.

“It’s not impossible. It just seems to be oddly optimistic.”

Whether life exists there depends on how old the planet is, Fich says.

“We don’t know how life evolves. The way life evolved on the Earth is that roughly half a billion years after the Earth’s surface cooled to the point where we had liquid water, there were micro-organisms on the Earth’s surface,” Fich says.

“And then from that point to getting intelligent life on the Earth took four billion years. And even three and a half billion years after the first life appeared on the Earth, we still didn’t have dinosaurs or anything like that.

“I don’t know how old that star and that planet are. Maybe they’re really old, and so there has been lots of time for life to evolve.

“But that’s like wild speculation. That’s further than I can go,” he says.

“I would say there’s a very good chance there’s liquid water on this planet, which means there’s a possibility that life could be formed there, or could be forming or there could be life that’s started there.”

The most likely life would be micro-organisms, but it could be anything, he says. “There could be intelligent life there . . . depending on how old the whole system is.”

Even if there was intelligent life, how would we know?

“We might pick up radio signals from there if they were beaming something at us. But remember it’s 690 light years away. It would take 690 years for the signal to get to us,” Fich says.

People on Earth started generating strong radio signals into space about 60 to 70 years ago, during the Second World War, Fich says. So they — if there is a “they” — can’t have heard from us yet, he says. But that doesn’t mean we don’t try.

“I think it’s a very strong chance that there’s life out there somewhere. I am not optimistic that we’ll find it in my lifetime. I’m going to guess it’s going to be hundreds of years before we’re going to see any signs of communicating life.”

Nevertheless, the discovery of Kepler-22b is significant, considering that 20 years ago scientists had no evidence there were other planets anywhere, Fich says.

“And now there are hundreds, maybe a thousand solar systems that are now known and there are thousands of candidates that Kepler has identified that they still have to show that there really is a planet.

“It could be four or five years from now, we’ll know of 10,000 solar systems, of which probably a few per cent of them will have terrestrial planets in the habitable zone.”

As for the question of whether we’re alone, “I think we’ll know that within a few hundred years.

“We’ll have heard from somebody,” he says. “They’ll be so far away that we won’t be able to communicate back and forth, but we’ll at least have heard.”

The question interests Fich, who is also a science fiction buff, “in a sort of distant way,” he says.

“You’d kind of like humanity to continue to improve itself, to continue to expand, to be a growing civilization. . . . We’re going to presumably expand and grow as a society and perhaps expand to other places in the universe besides the Earth.”