Solar System

It wasn’t that long ago that astronomers only knew of eight planets (nine before Pluto’s demotion back in 2006) – those here in our own solar system. Now we know of nearly 10,000 planets orbiting stars beyond our sun – known as exoplanets – and that flood of new worlds has ushered in something of a golden age for planetary scientists.

For astronomers like Marta Bryan, an assistant professor at the ��Ƶ Mississauga and in the David A. Dunlap department of astronomy and astrophysics in the Faculty of Arts & Science, it means there’s no better time to be studying these distant worlds.

“This is such a dynamic field,” says Bryan, who joined U of T in January after four years as a postdoctoral researcher at the University of California, Berkeley. Studying the properties of exoplanets provides “a unique opportunity to put ourselves and our world in the broadest of contexts – how does our solar system, our planet and our species fit into our universe?”

Bryan, who specializes in the study of planetary formation and evolution, was recently awarded the Annie Jump Cannon Award from the American Astronomical Society for her work on exoplanets.

As the tally of exoplanets began to grow, astronomers noticed how diverse planetary systems appear to be, with planets varying widely in size, composition and surface temperature. Some orbit very close to their host stars, while others follow orbits comparable to the Earth’s, or to the giant outer planets in our solar system.

“We’ve found thousands of exoplanets, with a huge diversity of properties,” Bryan says. “For me, one of the driving goals in the field is to understand where that diversity comes from. What does the process of planet formation and evolution look like?”

Marta Bryan uses a range of observational techniques to detect and characterize gas giant planets outside our solar system to explore how planetary systems form and evolve (photo by Nick Iwanyshyn)

While much research on exoplanets has focused on the search for Earth-like worlds, Bryan is interested in gas giant planets, analogous to Jupiter and Saturn in our own solar system. That’s because their sheer heft means they play an important role in determining how smaller planets in the same system evolve.

As Bryan puts it, gas giant planets “dominate the dynamics” of whatever system they’re in. Which means that learning about gas giants can, in fact, help us understand something about Earth-like planets – worlds whose evolution may have been affected by the presence of these much more massive bodies.

As a result, Bryan says, “gas giant planets are an obvious place to start if we want to understand the physics of planet formation.”

The gas giant planets in our own solar system are thought to have played a crucial role over the past five billion years. Jupiter, for example, is believed to have migrated inward before reversing direction and ending up in its current position. Jupiter’s foray into the inner part of the solar system is thought to have stunted the growth of the inner planets, particularly Mars, by scattering some of the gas and dust that might otherwise have been gravitationally pulled toward the red planet.

“We think that Jupiter and Saturn played a dominant role in the early history of our solar system, helping to shape the formation and evolution of our terrestrial planets,” Bryan says. “As a result, we want to understand in the broader extrasolar context what role gas-giant analogs to Jupiter and Saturn have played in shaping the lives of terrestrial worlds.”

The future looks bright – data from the James Webb Space Telescope is already pouring in. Bryan is especially excited about large, ground-based telescopes with mirrors up to 30 metres across, which are currently being planned. These next-generation telescopes may even reveal “biosignatures” on other worlds – signs of life that can be inferred from the composition of a planet’s atmosphere.

And if astronomers do end up finding conclusive evidence of life beyond our own planet, such a discovery “would definitely be transformational,” Bryan says.

#UofTGrad18 and Toronto Pride: Check out these June events

Romi Levine — Fri, 01 Jun 2018 04:00:00 +0000

#UofTGrad18 and Toronto Pride: Check out these June events

Romi Levine Fri, 06/01/2018 - 00:00

Cutline

This year's convocation ceremonies begin on June 7 (photo by Romi Levine)

Topic

Faculty of Applied Science & Engineering

Faculty of Arts & Science

Undergraduate Students

In less than a week, the ��Ƶ will once again be abuzz with students from all three campuses, sporting robes of all stripes, as they mark an important milestone in their academic career: convocation.

At the same time, LGBTQ Torontonians and their allies will be painting the city rainbow as they kick off this year’s Pride festivities, taking place at U of T and beyond.

There’s much to celebrate this month and plenty of events to choose from. Here are just a few of them:

June 1

It’s the beginning of Pride month in Toronto – launching on all three campuses with the raising of the Pride flag.

Attend the ceremony on your campus: downtown Toronto and U of T Mississauga, with a transgender flag-raising ceremony at U of T Scarborough on Saturday.

Catch up with old classmates at this year’s Alumni Reunion, taking place from now until June 3, featuring lunches and brunches galore and stress-free lectures on everything from dinosaurs to life on other planets.

June 2

U of T’s Faculty of Medicine is diving deep into the issue of the health implications of cannabis at a panel event in conjunction with the launch of UofTMed magazine’s latest edition.

June 3

Throughout the month, graduate students are invited to share their accomplishments on a chalkboard at the Grad Room on 66 Harbord St. as a way of reflecting on all of the great achievements and hard work that goes into graduate studies. Give yourself a pat on the back while you’re at it!

June 5

More than 1,000 elementary school students will be descending on U of T’s downtown Toronto campus for Go North Youth – the largest STEM event in Canada. Fifty classes from across the GTA of students from Grades 3 to 8 will be participating in a day of fun and learning with experts from U of T’s Faculty of Applied Science & Engineering and the department of computer science in the Faculty of Arts & Science, Google and Actua, Canada’s largest STEM outreach charity.

June 7

It’s the first day of convocation – check the events calendar for the full list of ceremony dates.

Make sure you head to the polls today to join Ontarians in deciding who will become our next premier. Haven't made your mind up yet? U of T Libraries has rounded up 10 tips to help you make an informed vote. Be sure to drop by the engagement station on the second floor of Robarts Library.

Head to the Jackman Law Building for a tour of its public spaces, including the Bora Laskin Law Library, classrooms and meeting rooms.

June 8

The annual Pride pub takes place this evening in the Hart House Quad. Come for the BBQ, drinks and good company and dance the night away with DJs and performers.

You'll hear the carillon bells during convocation, but this tour of Soldiers' Tower is a chance to see them up close and meet a carillonneur.

The Pride, U of T and Varsity flags flying together on the downtown Toronto campus (photo by Romi Levine)

June 10

Need to get away from Front Campus crowds? Come to the Grad Escape spring hike at Evergreen Brick Works for some fresh air and tasty treats at the farmers’ market.

June 11

U of T Mississauga’s International Education Centre global mobility co-ordinator Andrew Sedmihradsky and his eight-year-old son Max will stop at the Mississauga campus on their journey from Hamilton to Ottawa. The fourth annual father-son trip aims to help find a cure for Duchenne Muscular Dystrophy, in partnership with Professor Patrick Gunning and the Centre for Medicinal Chemistry at U of T Mississauga.

June 13

U of T Scarborough alumnus Tenniel Chu, vice chairman of Mission Hills Group, will share his success story as he transitioned from management classes at U of T to working in the sports management industry. Chu holds the Guinness World Record for owning/running the world’s largest golf resort. He also gave the ��Ƶ a $1.675-million gift in November to establish a sports management program at U of T Scarborough.

June 14

For new grads and current students alike, it’s tough to start the job search. There are plenty of sessions hosted by the Career Centre to help you on your journey, such as one taking place today on how to motivate yourself in the job search process.

June 20

Today’s the day to #DisplayYourPride. Every year, students, staff and faculty at all three campuses are encouraged to wear bright colours, decorate their work spaces, and share photos on all social media outlets using #displayyourpride.

June 21

Spend some time with U of T Scarborough Principal Bruce Kidd as he hosts his last Healthy Campus Walk. Tour through the ravine lands and to other notable locations, including the Lash Miller House. Meet at noon on the Humanities Wing Patio (HW).

June 22

Join U of T friends and colleagues for the Trans March at 8 p.m.

June 23

Lace up your shoes and join U of T’s team for the Pride & Remembrance Run, supporting and raising money for local LGBTQ organizations.

June 24

The Pride parade – Toronto Pride month’s grand finale – takes place today. Cheer on members of the U of T community and wave hello to Pride’s honoured guest Scott Jones and honoured youth Cho Chua – both U of T students.

June 26

The second-annual Black Graduation will be celebrating the achievements of Black-identifying students at the ��Ƶ who are a part of the Class of 2018. The Black Graduation celebration allows for students, family and friends to come together in one setting to celebrate their hard work and dedication.

Google and Netflix use it: algorithms can also predict our solar system's stability, say U of T researchers

ullahnor — Thu, 01 Dec 2016 21:37:14 +0000

Google and Netflix use it: algorithms can also predict our solar system's stability, say U of T researchers

ullahnor Thu, 12/01/2016 - 16:37

Cutline

Artist's depiction of a collision between two planetary bodies (photo illustration by NASA/JPL-Caltech)

Don Campbell

Author legacy

Don Campbell

Topic

Global Lens

Solar System

machine learning

Artificial Intelligence

UTSC

U of T Scarborough

Machine learning is used today for everything from detecting fraud and sorting spam in Google to recommending movies on Netflix.

Now a team of ��Ƶ researchers has developed a novel approach to using algorithms to determine whether planetary systems are stable.

“Machine learning offers a powerful way to tackle a problem in astrophysics, and that’s predicting whether planetary systems are stable,” says Dan Tamayo, lead author of a report published online in the Astrophysical Journal Letters.

The postdoctoral researcher in the Centre for Planetary Science at U of T Scarborough and his team have developed a method that's 1,000 times faster than traditional means of predicting solar system stability.

Planetary system stability can tell us a great deal about how these systems formed, Tamayo said, adding that it can also offer valuable new information about exoplanets that is not offered by current methods of observation.

The findings could come in handy when analyzing data from NASA’s Transiting Exoplanet Survey Satellite (TESS) set to launch next year. The two-year mission will focus on discovering new exoplanets by focusing on the brightest stars near our solar system.

“It could be a useful tool because predicting stability would allow us to learn more about the system from the upper limits of mass to the eccentricities of these planets,” says Tamayo. “It could be a very useful tool in better understanding those systems.”

U of T Scarborough planetary science researcher Dan Tamayo wants to use algorithms to study solar system stability (photo by Ken Jones)

There are several methods of detecting exoplanets that provide information such as the size of the planet and its orbital period. But they may not provide the planet’s mass or how elliptical their orbit is, which are all factors that affect stability, notes Tamayo.

“In the past we’ve been hamstrung in trying to figure out whether planetary systems are stable by methods that couldn’t handle the amount of data we were throwing at it,” he says.

The method developed by Tamayo and his team is the result of a series of workshops at U of T Scarborough covering how machine learning could help tackle specific scientific problems.

“What’s encouraging is that our findings tell us that investing weeks of computation to train machine learning models is worth it because not only is this tool accurate, it also works much faster,” he adds.