Centre for Planetary Sciences

Can life exist on a 'snowball' planet? New 91�Թ� research says yes

noreen.rasbach — Tue, 06 Aug 2019 16:09:36 +0000

Can life exist on a 'snowball' planet? New 91�Թ� research says yes

noreen.rasbach Tue, 08/06/2019 - 12:09

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“What our research suggests is that snowball planets – that is, those with oceans that are completely covered in sea ice – shouldn’t be excluded as being inhospitable to life," says Adiv Paradise, lead author of the study (photo by Nick Iwanyshyn)

Don Campbell

Topic

Breaking Research

Centre for Planetary Sciences

Graduate Students

Research & Innovation

91�Թ� Scarborough

A new 91�Թ� study is challenging the definition of what makes a planet hospitable to life, finding that “snowball” planets may harbour the necessary conditions.

“When we think of a habitable planet, we tend to imagine a relatively warm place like Earth,” says Adiv Paradise, a PhD candidate in the department of astronomy and astrophysics and lead author of the study.

“What our research suggests is that snowball planets – that is, those with oceans that are completely covered in sea ice – shouldn’t be excluded as being inhospitable to life.”

For the study, Paradise and his colleagues, including supervisor Kristen Menou, associate professor in the department of physical and environmental sciences at 91�Թ� Scarborough and the Centre for Planetary Sciences, ran thousands of three-dimensional computer simulations of planets in the inner habitable zone with Earth-like climates.

What they found is that if there are areas of dark, bare ground that receive enough sunlight, those regions can be warm enough for liquid water and life, without causing the ice to retreat.

“These planets may get a similar amount of light as Earth and the temperature will be above freezing, but unlike Earth, they are trapped in a snowball state where the rest of the planet remains frozen.”

According to geological evidence, Earth has entered into a snowball state at least twice. The most recent was about a billion years ago and it lasted for tens of millions of years.

What likely triggered Earth’s emergence from its snowball state was the large accumulation of carbon dioxide (CO₂) in the atmosphere released mostly by volcanoes over millions of years. Once out of snowball, rain triggered by warming temperatures removed CO₂out of the air, where it was absorbed in rocks and soil. This balanced the CO₂ being added by volcanoes and helped stabilize warm conditions globally.

With a permanent snowball planet, CO₂is being removed faster than the rate at which it’s being put back through volcanoes. This can cause a planet to enter a snowball state, but it will only get locked into that state if the rate at which CO₂is removed (through rainfall on those patches of warm land) can balance the rate at which volcanoes are putting it back.

“What we’re arguing here is that we shouldn’t write off snowball planets as being inhospitable to life,” Paradise says.

“Some of the habitable planets we discover are going to be quite different from ours in terms of weather and climate, so we should reconcile ourselves to that fact.”

The study, which is published in the journal Geophysical Research: Planets, received funding from Natural Sciences and Engineering Research Council of Canada (NSERC).

There’s no way to know what percentage of exoplanets (those outside our solar system) are in a snowball state. As Paradise points out, the only way to find out at the moment would be to physically observe them, which is impossible with current telescopes.

He says another lingering question is how much CO₂ is on an average planet, and how volcanically active the average planet is compared to Earth.

“If most planets are less volcanically active than Earth, you might expect a significant fraction of them to be in snowball. At the same time, if Earth is less volcanically active than most, you’d expect snowball planets to be rare.”

As for what life on these snowball planets may look like, Paradise says it would most likely be aquatic. The Earth descended into a snowball state right after life first began to emerge, and it was entirely aquatic.

“With these snowball planets that we’re looking at, the ocean waters beneath the ice likely wouldn’t be radically different from the waters in the Arctic Ocean on Earth,” Paradise says.

Interstellar asteroid that recently flew past Earth likely came from a system with two stars: 91�Թ� research

noreen.rasbach — Mon, 19 Mar 2018 17:21:49 +0000

Interstellar asteroid that recently flew past Earth likely came from a system with two stars: 91�Թ� research

noreen.rasbach Mon, 03/19/2018 - 13:21

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An artist's rendering of ’Oumuamua, the rocky object that puzzled scientists

Don Campbell

Topic

Our Community

Centre for Planetary Sciences

Global

Research & Innovation

Space

91�Թ� Scarborough

New 91�Թ� research has found that the rocky object that puzzled scientists by barrelling through our solar system seemingly out of nowhere very likely came from a binary star system.

“It’s remarkable that we’ve now seen for the first time a physical object from outside our solar system,” says the study's lead author Alan Jackson, a postdoctoral researcher at the Centre for Planetary Sciences at 91�Թ� Scarborough. The study has garnered international headlines.

The object, called ’Oumuamua which means “scout” in Hawaiian, was discovered by the Haleakala Observatory in Hawaii on Oct. 19. With a radius of 200 metres and travelling at a blistering speed of 30 kilometres per second, the closest approach it made to Earth was about 33 million kilometres.

At first researchers assumed it must be a comet, one of countless icy objects that release gas when it warms up as it approaches the sun. But it didn’t show any comet-like activity as it neared the sun, and was quickly reclassified as an asteroid, meaning it was rocky.

For the study, Jackson and his co-authors set about testing how efficient binary star systems are at ejecting objects, and they also looked at how common these star systems are in the galaxy. Their findings are making headlines around the world:

Read about the research in Popular Mechanics

Read about the research in Scientific American

Read about the research in The Guardian

Read about the research in the Daily Mail

They found that rocky objects like ’Oumuamua are far more likely to come from binary than single star systems. They were also able to determine that rocky objects are ejected from binary systems in comparable numbers to icy objects.

“It’s really odd that the first object we would see from outside our system would be an asteroid because a comet would be a lot easier to spot,” says Jackson, who specializes in planet and solar system formation.

Once they determined that binary systems are very efficient at ejecting rocky objects, and that a sufficient number of them exist, they were satisfied that ’Oumuamua very likely came from a binary system. They also concluded that it likely came from a system with a relatively hot, high mass star since such a system would have a greater number of rocky objects closer in.

A binary star system, unlike our own solar system, has two stars orbiting a common centre. The researchers suggest that ’Oumuamua was very likely ejected from a binary system sometime during planet formation.

Alan Jackson, a postdoctoral researcher at the Centre for Planetary Sciences at 91�Թ� Scarborough (photo by Ken Jones)

Researchers were also pretty sure it was from outside our solar system based on its trajectory and high speed.

The research, which began this past October and was published in the Monthly Notices of the Royal Astronomical Society, was an intensive project for Jackson and his co-authors. The fact that ’Oumuamua was classified as an asteroid piqued his curiosity, and the driving motivation was figuring out the big unanswered question of where it came from.

As a starting point, Jackson says it’s important to understand that in order for an object to be ejected from a star system it needs to interact with something big. In single star systems like our own, comets make up the vast majority of objects that are ejected because they form farther away and are less bound by the gravity of the sun.

“Comets can be thrown out of our solar system by interacting with Jupiter, which is a big object, but we also have some idea that Jupiter-sized planets are not that common,” he says.

Past research has found that only three to 10 per cent of star systems contain Jupiter-sized planets. But another large object that can easily eject something could be another star.

Major questions about ’Oumuamua remain, notes Jackson. Researchers are trying to determine how it got its cigar-like shape and from where it may have originated.

“It’s very difficult to track exactly where it came from with any great precision,” he says.

For planetary scientists like Jackson, being able to observe objects like ’Oumuamua may yield important clues about how planet formation works in other star systems.

“The same way we use comets to better understand planet formation in our own solar system, maybe this curious object can tell us more about how planets form in other systems.”

Using AI to count craters on the moon at 91�Թ�'s Centre for Planetary Sciences

lanthierj — Mon, 12 Mar 2018 13:53:01 +0000

Using AI to count craters on the moon at 91�Թ�'s Centre for Planetary Sciences

lanthierj Mon, 03/12/2018 - 09:53

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This is a detailed view of the back side of moon in the vicinity of Crater No. 308 taken during the Apollo 11 mission (photo courtesy of NASA)

Don Campbell

Topic

Global Lens

Alumni

Artificial Intelligence

Centre for Planetary Sciences

Graduate Students

Research & Innovation

91�Թ� Scarborough

A new technique developed by researchers at the 91�Թ� is using the technology behind self-driving cars to measure the size and location of crater impacts on the moon.

“When it comes to counting craters on the moon, it’s a pretty archaic method,” says Mohamad Ali-Dib, a postdoctoral researcher at the Centre for Planetary Sciences (CPS) at 91�Թ� Scarborough.

“Basically we need to manually look at an image, locate and count the craters and then calculate how large they are based off the size of the image. Here we’ve developed a technique from artificial intelligence that can automate this entire process that saves significant time and effort.”

Researchers have tried in the past to develop algorithms that could identify and count lunar craters but when they were used on new, previously unseen patches of craters they tended to perform poorly.

Mohamad Ali-Dib, a postdoctoral researcher at the Centre for Planetary Sciences at 91�Թ� Scarborough (photo by Ken Jones)

“It’s the first time we have an algorithm that can detect craters really well, for not only parts of the moon, but also areas of Mercury,” says Ali-Dib, who developed the technique along with alumnus Ari Silburt, postdoctoral researcher Chenchong Charles Zhu, and a group of researchers at CPS and the Canadian Institute for Theoretical Astrophysics (CITA).

In order to determine its accuracy, the researchers first trained the neural network on a large data set covering two-thirds of the moon, and then tested their trained network on the remaining third of the moon. It worked so well that it was able to identify twice as many craters as traditional manual counting. In fact, it was able to identify about 6,000 previously unidentified craters on the moon.

The technique itself relies on a convolutional neural network, a class of machine learning algorithms that has been successfully used for computer vision to power robots and even self-driving cars. The data used by the algorithms was taken from elevation maps gathered from orbiting satellites.

While none of the researchers had previous experience in crater counting, they were able to develop the technique as a result of a series of workshops held at 91�Թ� Scarborough, co-organized by Associate Professor Kristen Menou, on how machine learning and deep learning could help tackle specific scientific problems.

Ari Silburt, a former graduate student in the department of astronomy and astrophysics, is now a postdoc at Penn State University

“Tens of thousands of unidentified small craters are on the moon, and it’s unrealistic for humans to efficiently characterize them all by eye,” says Silburt. A former graduate student in 91�Թ�’s department of astronomy and astrophysics, Silburt is now a postdoc at Penn State University.

“There’s real potential for machines to help identify these small craters and reveal undiscovered clues about the formation of our solar system.”

Knowing the size and location of craters on bodies like the moon is important because it offers a window into the history of our solar system. By studying impact craters of all shapes, sizes and ages, researchers can better understand the distribution of material and the physics that occurred in the early stages of our solar system, notes Ali-Dib.

Since the moon lacks an atmosphere, plate tectonics and water, there is little erosion and as a result some impact craters as old as 4 billion years are visible. The ages of large craters can also be determined by counting how many small craters are found inside it.

“For this technique to work you need an airless body like the moon or Mercury, bodies where there’s little erosion taking place,” adds Ali-Dib.

As for next steps, Ali-Dib says the plan is to further improve the algorithm to allow researchers to find more craters, and to also test it on other solar system bodies like Mars, Ceres and the icy moons of Jupiter and Saturn.

The research, which is currently under review in the journal Icarus, received funding from the Natural Sciences and Engineering Research Council of Canada (NSERC).

Tesla shot into space will likely collide with Earth or Venus – in millions of years: 91�Թ� researchers

noreen.rasbach — Thu, 15 Feb 2018 19:45:35 +0000

Tesla shot into space will likely collide with Earth or Venus – in millions of years: 91�Թ� researchers

noreen.rasbach Thu, 02/15/2018 - 14:45

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Researchers at the Centre for Planetary Sciences have found that the Tesla Roadster recently sent into space as part of SpaceX's test flight will eventually collide with Earth or Venus (photo courtesy of SpaceX)

Topic

Global Lens

Centre for Planetary Sciences

Global

Space

91�Թ� Scarborough

The Tesla Roadster that was recently shot into space as part of SpaceX’s rocket test flight will likely collide with Earth or Venus eventually, according to new 91�Թ� research.

“It will likely end up colliding with Earth or Venus, but there’s no need to panic since the probability of that happening even within the next million years is very small,” says the research's author Hanno Rein, an assistant professor of physics at 91�Թ� Scarborough and director of the Centre for Planetary Sciences.

The car was sent into space as part of the payload for SpaceX’s Falcon Heavy test flight on Feb. 6. While rocket test flights usually have a dummy payload, SpaceX founder Elon Musk sent up his personal Tesla Roadster instead.

Though it’s mostly a publicity stunt – the car doesn’t have any scientific instruments on board – it’s now classified as a near-earth object, meaning it is catalogued and being tracked by NASA’s Jet Propulsion Laboratory along with other objects that will travel relatively close to Earth.

Read about the research on BBC News

Read about the research on CBC News

What motivated Rein and his team was the question of what will be the car’s long-term fate. After running a series of simulations using sophisticated software that can track the motion of objects in space, they determined the probability of it colliding with Earth and Venus over the next one million years to be six per cent and 2.5 per cent, respectively.

They also determined that the first close encounter the Tesla will have with us will be in 2091, when it will pass within a few hundred thousand kilometres of Earth.

Assistant Professor Hanno Rein (left) and postdoctoral fellow Dan Tamayo from the Centre for Planetary Sciences wanted to see what the long-term fate of the Tesla Roadster would be after it was launched into space (photo by Ken Jones)

The car is currently on a Mars and Earth crossing orbit, meaning it will travel on an elliptical path that repeatedly carries it beyond Mars and then back to Earth’s orbital distance from the sun. How the car's orbit evolves over time will depend a lot on its encounters with Earth, especially how close it will get to Earth since any small change in its trajectory could have a large effect on its orbit.

While the path of the Tesla can be accurately predicted in terms of years, after hundreds of years and many close encounters with Earth it becomes impossible to predict the object’s precise orbit. By studying a large number of orbital simulations, however, the researchers were able to arrive at a statistical distribution of possible outcomes.

Read: Out of this world: 91�Թ� student's SpaceX internship involved working on Falcon Heavy's engines

“Each time it passes Earth, the car will get a gravitational kick,” says Dan Tamayo, a postdoctoral fellow at 91�Թ� Scarborough who is a co-author on the paper that has yet to be published.

“Depending on the details of these encounters, the Tesla can be kicked onto a wider or smaller orbit, so it’s random. Over time the orbit will undergo what’s called a random walk, similar to the fluctuations we see in the stock market, that will allow it to wander the inner solar system.”

While they only ran simulations for the first three million years of its space journey, Rein says the most likely outcome for the Tesla is for it to crash into Earth or Venus in the next 10 million years or so.

“Although we are not able to tell on which planet the car will ultimately end up, we’re comfortable saying it won’t survive in space for more than a few tens of millions of years,” he says.

While the car’s likely final destination is Earth, they note there’s nothing to fear since much or all of it will likely burn up in the atmosphere.

The research, which received funding from the Natural Sciences and Engineering Research Council of Canada (NSERC), has been submitted for publication. A preprint of the paper is available online.

91�Թ� astrophysicist-musician helps blind, partially sighted experience the cosmos with musical planetarium show

Romi Levine — Wed, 24 Jan 2018 18:25:12 +0000

91�Թ� astrophysicist-musician helps blind, partially sighted experience the cosmos with musical planetarium show

Romi Levine Wed, 01/24/2018 - 13:25

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Astrophysicist Matt Russo makes music using the movements of objects in space (photo by Romi Levine)

Romi Levine

Topic

Our Community

Canadian Institute for Theoretical Astrophysics

Centre for Planetary Sciences

Faculty of Arts & Science

91�Թ� Scarborough

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"It's kind of like there's an electric guitar in space and I'm plugging in the cable"

Robyn Rennie hasn’t seen the night sky for almost 13 years.

She has centrocecal vision loss, a condition that stemmed from an illness, leaving her with only peripheral vision and a loonie-sized area of vision at the centre.

“When I'm looking at the normal night sky, I'll see something at the corner of my eye twinkling but when I turn to look at it directly, I can't see it anymore,” she says.

She says she misses being able to spot Orion from the window of her Orillia home. She used to find it constant and comforting.

Wanting to help her mother relive that experience, Rennie’s daughter Erin decided to contact 91�Թ�’s planetarium to see if there was something they could do.

She came to the right place.

Erin was put in contact with Matt Russo, a planetarium operator at 91�Թ�, formerly a postdoctoral researcher at the Canadian Institute for Theoretical Astrophysics (CITA) in 91�Թ�'s Faculty of Arts & Science.

Russo is both an astrophysicist and a musician. He decided to combine his passions to create music out of the movement of objects in space alongside Dan Tamayo, a postdoctoral researcher at CITA and the Centre for Planetary Sciences at 91�Թ� Scarborough, and friend and band mate Andrew Santaguida. Their musical project is called SYSTEM Sounds.

Read about Matt Russo's musical process

When Erin got in touch, Russo just happened to be designing a planetarium show geared towards the blind and partially sighted. He invited Rennie and her family to come to 91�Թ� for a preview.

“My son came from Belleville and my brother came from Wasaga Beach. Everybody came down to Toronto for the day,” says Rennie.

Rennie and her family were blown away. “We were all so impressed. We couldn't believe it.”

Russo is now bringing the unique experience to the public with Our Musical Universe, an audio-focused planetarium show debuting this Friday at the 91�Թ� Planetarium on the downtown Toronto campus, presented by the Dunlap Institute for Astronomy & Astrophysics.

Read about Our Musical Universe in the Globe and Mail

Read the transcript from the audio story

Attendees will hear the sound of a night sky full of stars, fly through the solar system and hear the rings of Saturn and the moons of Jupiter, listen to deep space through the sounds of the Voyager probe and hear the afterglow of the Big Bang, says Russo.

To make this genre of cosmic music, Russo and his colleagues use the rhythm of planets orbiting and the pitch from speeding up the sound of planets oscillating by around 200 million times, he says.

“The music is out there,” says Russo. “I'm just finding a way to make it audible. It's kind of like there's an electric guitar in space and I'm plugging in the cable.”

When Russo began releasing “space music,” as he calls it, he was contacted by people who were blind or partially sighted who said they were thankful for having a way to experience and engage with astronomy. This was the driving force behind creating the planetarium show, he says.

“There's something special about music in that it flows in time and it flows in time at the same rate for everybody that's listening to it,” says Russo. “It has a way of synchronizing everybody's emotions and their experiences of a certain event in a way that visual images can't.”

In addition to the audio and visual presentation, Russo’s planetarium show will offer a tactile experience.

People will be able to feel Saturn’s rings on a three-foot-long wood carving, touch the spiral arms of a galaxy or the cloud bands of jupiter, and hold 3D-printed constellations.

“They can feel the bumps and lines to feel the shapes of the constellations in the night sky,” says Russo.

Inspired by her trip to the planetarium, Rennie, who is an artist, created a painting called “Myth,” using textures and rich colours to tell the story of how she sees the universe.

“Stories are the same. Stories are always open to interpretation,” she says.

Myth, a painting by Robyn Rennie

91�Թ� researcher finds Earth-like conditions in little-known exoplanet – and discovers a new planet

ullahnor — Tue, 05 Dec 2017 17:19:51 +0000

91�Թ� researcher finds Earth-like conditions in little-known exoplanet – and discovers a new planet

ullahnor Tue, 12/05/2017 - 12:19

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Researchers at the Centre for Planetary Sciences at 91�Թ� Scarborough have found that K2-18b could be a scaled-up version of Earth and discovered it has a neighbouring planet (illustration by Alex Boersma)

Don Campbell

Topic

Global Lens

Astronomy & Astrophysics

Centre for Planetary Sciences

Global

91�Թ� Scarborough

A 91�Թ� PhD student has found that a little-known exoplanet called K2-18b could be a “super-Earth,” and in the process discovered a new planet in the same solar system.

The researcher, who had set a goal to discover a new exoplanet for his thesis, made the discovery by scouring data collected by the European Southern Observatory (ESO).

“Being able to measure the mass and density of K2-18b was tremendous, but to discover a new exoplanet was lucky and equally exciting,” says Ryan Cloutier, a PhD student in 91�Թ� Scarborough’s Centre for Planetary Science, 91�Թ�’s department of astronomy and astrophysics in the Faculty of Arts & Science and the Université de Montréal Institute.

Both planets orbit K2-18, a red-dwarf star located about 111 light-years away in the constellation Leo. When the planet K2-18b was first discovered in 2015, it was found to be orbiting within the star’s habitable zone, making it an ideal candidate to have liquid surface water, a key element in harbouring conditions for life as we know it.

“It wasn’t a eureka moment because we still had to go through a checklist of things to do in order to verify the data,” Cloutier said. “Once all the boxes were checked it sunk in that, wow, this actually is a planet.”

Interested in publicly funded research in Canada? Learn more at UofT’s #supportthereport advocacy campaign

The James Webb Space Telescope, which will be launched in 2019, will be instrumental in collecting a range of data for studying the solar system, early universe and exoplanets.

“There’s a lot of demand to use this telescope, so you have to be meticulous in choosing which exoplanets to look at,” says René Doyon, a co-author on the paper who is with Université de Montréal Institute and a principal investigator for NIRISS, which is the Canadian Space Agency instrument on board the James Webb Space Telescope.

“K2-18b is now one of the best targets for atmospheric study, it’s going to the near top of the list.”

It was while looking through the data of K2-18b that Cloutier noticed something unusual. In addition to a signal occurring every 39 days from the rotation of K2-18, and one taking place every 33 days from the orbit of K2-18b, he noticed a different signal occurring every nine days.

Who kicked a giant planet out of our Solar System 4 billion years ago? We're looking at you, Jupiter

sgupta — Thu, 29 Oct 2015 12:40:59 +0000

Who kicked a giant planet out of our Solar System 4 billion years ago? We're looking at you, Jupiter sgupta Thu, 10/29/2015 - 08:40

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Don't be fooled by Jupiter's romantic exterior (image courtesy NASA/JPL/Space Science Institute)

Sean Bettam

Author legacy

Sean Bettam

Topic

Breaking Research

Centre for Planetary Sciences

Can life exist on a 'snowball' planet? New 91�Թ� research says yes

Interstellar asteroid that recently flew past Earth likely came from a system with two stars: 91�Թ� research

Read about the research in Popular Mechanics

Read about the research in Scientific American

Read about the research in The Guardian

Read about the research in the Daily Mail

Using AI to count craters on the moon at 91�Թ�'s Centre for Planetary Sciences

Tesla shot into space will likely collide with Earth or Venus – in millions of years: 91�Թ� researchers

Read about the research on BBC News

Read about the research on CBC News

Read: Out of this world: 91�Թ� student's SpaceX internship involved working on Falcon Heavy's engines

91�Թ� astrophysicist-musician helps blind, partially sighted experience the cosmos with musical planetarium show

Read about Matt Russo's musical process

Read about Our Musical Universe in the Globe and Mail

91�Թ� researcher finds Earth-like conditions in little-known exoplanet – and discovers a new planet

Read more at CBC News

Read more at CTV News

Interested in publicly funded research in Canada? Learn more at UofT’s #supportthereport advocacy campaign

Read more in the San Francisco Chronicle, the International Business Times and the India Times

Who kicked a giant planet out of our Solar System 4 billion years ago? We're looking at you, Jupiter