Canadian planet hunter seeking alien life

‘The shifting line of what is crazy’ says Toronto-born astrophysicist

Sara Seager has pledged to spend the rest of her life searching for another Earth among the billions of stars that inhabit our night sky.

“That’s our goal: to find life out there,” the Toronto-born astrophysicist says in a distinctly assured monotone, as if describing a walk to the local mall.

The highly acclaimed professor, who is scheduled to deliver a lecture on the heady topic later this week in Halifax, says the lofty objective is well within reach for the first time in human history.

And she should know.

“Forty years ago, people got laughed at when they searched for exoplanets,” she says, referring to planets found beyond our solar system. “It was considered incredibly fringe because it’s so hard … But there’s this shifting line of what is crazy.”

Seager, who teaches at the Massachusetts Institute of Technology, is considered one of the world’s leading experts on exoplanets. She has been profiled by The New York Times, CNN and Cosmopolitan, and won a MacArthur “genius” grant.

In the field of astronomy, she is a certified rock star.

Ultimately, her research could help answer some of the biggest questions facing humankind. But first, Seager and her team have plenty of work to do.

And that’s what she plans to talk about Friday when she delivers the third annual MacLennan Memorial Lecture at Saint Mary’s University.

Her mission to find alien life somewhere in the cosmos may sound like it was borrowed from an episode of “The-X Files,” but recent advances in astrophysics suggest this pioneer of planet hunting has good reason to be optimistic.

Prior to the 1990s, only two planets — Uranus and Neptune — had been discovered in the 4,000 years since the Babylonians looked up and recorded the celestial comings and goings of visible stars and planets. Pluto wasn’t spotted until 1930, but it was demoted to dwarf planet status in 2006.

There was a huge breakthrough in 1995, when two Swiss astronomers announced they had found the first planet outside our solar system orbiting a sun-like star. They called it 51 Pegasi B. Its existence was inferred by measurements showing its gravity is causing the star to wobble.

And then in 2014, NASA’s Kepler Space Telescope was used to find Kepler-186f, the first Earth-sized exoplanet in a star’s so-called Goldilocks zone.

“It’s where a planet is not too hot, and not too cold, but just right for life,” says Seager.

Thanks to rapidly improving computers and detection equipment, scientists have found more than 3,600 exoplanets in the past 30 years.

However, only 52 of them are in that habitable zone, where water in its liquid form may exist.

But being in the zone doesn’t automatically mean an Earth-sized exoplanet could support life as we know it.

“Until we can study the planet’s atmosphere … we really won’t know anything about that planet,” says Seager. “It doesn’t really mean anything until we get a better look.”

That’s not as easy at it sounds. Many of the recently discovered exoplanets are too far from Earth for direct observation.

But a tantalizing solution may have presented itself in August 2016, when researchers at the European Southern Observatory in Chile detected an Earth-sized exoplanet orbiting the habitable zone of the red dwarf Proxima Centauri, our solar system’s nearest neighbouring star at only 4.2 light years away.

That’s about 40 trillion kilometres away, but it’s still about 10 times closer than Kepler-186f.

“It was right next door, although very hard to find,” says Seager. “In astronomy, close really matters.”

Still, directly observing a relatively small planet that closely orbits a much larger star is tough because the intense light generated by the star must be blocked.

“Planets don’t have energy,” says Seager, “All they’re doing is reflecting light from the star. They’re like the little kid on the block … It’s hard for them to shine.”

That’s why the planetary scientist is working with NASA and Northrop Grumman to develop Starshade, which will be shaped like a daisy and stand taller than a 15-storey building. Deployed by spacecraft, the petal-shaped panels — first proposed in the early 1960s — would block waves of starlight that would otherwise overwhelm an accompanying space telescope.

“That’s my favourite project,” says Seager. “One of my life’s goals would be to make Starshade happen.”

She wants to adapt a new space telescope — the Wide-Field Infrared Survey Telescope or WFirst — to make it “Starshade ready” by the time it is ready for launch in the 2020s.

With Starshade, Seager hopes to study the atmospheres of exoplanets to determine if they have oxygen and other gasses that may indicate they are supporting alien life.

“When I help find all these planets, the goal is to … look for signs of life by way of gasses (like oxygen) that don’t belong,” she says. “We won’t even be 100 per cent sure that it’s made by life … And if it is, we won’t know if it’s intelligent beings or just slime.”

Seager recalls her introduction to astronomy, while growing up in Toronto, was attending her first outdoor “star party,” where amateur astronomers gather under dark skies to share their knowledge — and their telescopes.

Though her father David — a well-known expert in hair-transplant procedures — would try to dissuade her from becoming an astronomer, Seager would later earn a bachelor of science in math and physics at the University of Toronto, before earning a PhD in astronomy at Harvard.

She says the math suggests there is life out there. But finding it won’t be easy, given the vastness of space.

“I know that it could be a multigenerational search,” Seager says. “It could be a really, really long time.”

Michael MacDonald, The Canadian Press

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

NDP headquarters on election night, Oct. 24, 2020. (Katya Slepian/Black Press Media)
ELECTION 2020: Live blog from B.C. party headquarters

BC NDP projected to win majority government – but celebrations will look different this election

B.C. Green Party leader Sonia Furstenau outlines her party's climate action platform at Nanaimo's Vancouver Island Conference Centre earlier this month. (News Bulletin file photo)
Green leader Furstenau declared victor in her home riding on Vancouver Island

Cowichan Valley voters elect freshly minted party leader for her second term

Submitted
BC VOTES 2020: John Rustad re-elected in Nechako Lakes riding

The result is based on preliminary vote count and the final results will be available after Nov.6

John Horgan has been re-elected the MLA for Langford-Juan de Fuca. (File-Black Press)
Horgan trounces challengers to be re-elected in his Vancouver Island riding

MLA has represented constituency of Langford-Juan de Fuca and its predecessors since 2005

The track washrooms will be opened up again next year in May. (Priyanka Ketkar photo/Lakes District News)
Toilets, sinks torn off, graffiti on walls at the Burns Lake track washroom

“Seems to happen once or twice a year” says the Village CAO on the vandalized track washroom

NDP Leader John Horgan celebrates his election win in the British Columbia provincial election in downtown Vancouver, B.C., Saturday, Oct. 24, 2020. THE CANADIAN PRESS/Jonathan Hayward
Horgan celebrates projected majority NDP government, but no deadline for $1,000 deposit

Premier-elect says majority government will allow him to tackle issues across all of B.C.

FILE – Prime Minister Justin Trudeau greets Premier John Horgan during a press conference at the BC Transit corporate office following an announcement about new investments to improve transit for citizens in the province while in Victoria on Thursday, July 18, 2019. THE CANADIAN PRESS/Chad Hipolito
Trudeau congratulates Horgan on NDP’s election victory in British Columbia

Final count won’t be available for three weeks due to the record number of 525,000 ballots cast by mail

Comedic actor Seth Rogen, right, and business partner Evan Goldberg pose in this undated handout photo. When actor Seth Rogen was growing up and smoking cannabis in Vancouver, he recalls there was a constant cloud of shame around the substance that still lingers. Rogen is determined to change that. (Maarten de Boer ohoto)
Seth Rogen talks about fighting cannabis stigma, why pot should be as accepted as beer

‘I smoke weed all day and every day and have for 20 years’

Provincial Green Party leader Sonia Furstenau speaks at Provincial Green Party headquarters at the Delta Victoria Ocean Pointe in Victoria. (Arnold Lim / Black Press)
VIDEO: Furstenau leads BC Greens to win first riding outside of Vancouver Island

Sonia Furstenau became leader of BC Greens one week before snap election was called

NDP Leader John Horgan elbow bumps NDP candidate Coquitlam-Burke Mountain candidate Fin Donnelly following a seniors round table in Coquitlam, B.C., Tuesday, October 20, 2020. THE CANADIAN PRESS/Jonathan Hayward
Horgan, NDP head for majority in B.C. election results

Record number of mail-in ballots may shift results

Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

The Canadian border is pictured at the Peace Arch Canada/USA border crossing in Surrey, B.C. Friday, March 20, 2020. More than 4.6 million people have arrived in Canada since the border closed last March and fewer than one-quarter of them were ordered to quarantine while the rest were deemed “essential” and exempted from quarantining. THE CANADIAN PRESS/Jonathan Hayward
Majority of international travellers since March deemed ‘essential’, avoid quarantine

As of Oct. 20, 3.5 million travellers had been deemed essential, and another 1.1 million were considered non-essential

Canada’s Chief Public Health Officer Theresa Tam responds to a question during a news conference Friday October 23, 2020 in Ottawa. Canada’s top physician says she fears the number of COVID-19 hospitalizations and deaths may increase in the coming weeks as the second wave continues to drive the death toll toward 10,000. THE CANADIAN PRESS/Adrian Wyld
Canada’s top doctor warns severe illness likely to rise, trailing spike in COVID-19 cases

Average daily deaths from virus reached 23 over the past seven days, up from six deaths six weeks ago

Most Read