A time-lapse of Supernova 1987A

PhD student Yvette Cendes models the aftermath of the supergiant star

A time-lapse of Supernova 1987A

Yvette Cendes, a PhD student in the Dunlap Institute for Astronomy & Astrophysics, used mathematical modeling to visualize a time-lapse of the aftermath of Supernova 1987A.

Based on existing quantitative data, the time-lapse observes the supernova’s shockwave — a powerful wave that causes a star to explode in space — from 1992–2017.

Since publishing her team’s findings in The Astrophysical Journal, Cendes has delivered several talks about Supernova 1987A.

The significance of the time-lapse

The team’s analyses show that the “expanding remnant” of the supernova is shaped like a three-dimensional torus, or donut, rather than a two-dimensional ring.

Cendes applied statistical and mathematical techniques to the time-lapse to show that the supernova produced a shockwave expanding outward and slamming into debris that ringed the original star before its demise.

As a result of the growing torus punching “through the ring of debris,” the supernova’s shockwave has accelerated, increasing in speed by some one thousand kilometres per second.

The team also found that the shockwave from the supernova models a classic shockwave system.

A principle similar to a shockwave can be seen when a rock creates ripples in a pond. In space, however, a shockwave operates on a much larger magnitude and causes a supernova to explode.

This explosion produces supernova remnants, which are seen in the donut-shape formation of Supernova 1987A.

The origins of Supernova 1987A

U of T astronomer Ian Shelton and telescope operator Oscar Duhalde discovered Supernova 1987A on February 24, 1987. The pair was the first to observe the death of the supergiant star and its resultant explosion from the Las Campanas Observatory in northern Chile.

Despite being 168,000 light-years — or 1.6 quintillion kilometres — away from Earth, Supernova 1987A has been the brightest supernova to appear in our skies since Kepler’s Supernova in 1604.

According to NASA, the supernova “blazed with the power of 100 million suns” for “several months following its discovery.”

While 1.6 quintillion kilometres might seem like a titanic distance, Supernova 1987A is “the closest supernova to us that we’ve observed since the invention of the telescope,” said Cendes in an interview with The Varsity.

This helps to explain Supernova 1987A’s brightness and why it is one of the most studied objects in astronomy.

The aftermath of Supernova 1987A

Under the supervision of U of T professor Bryan Gaensler, Cendes spent nine months analyzing data from 1992 to 2017, collected from a radio telescope called the CSIRO Australia Telescope Compact Array.

Cendes’ initial challenge was learning how to translate the raw radio data from the Compact Array into images, which she eventually presented in her time-lapse.

Since this was her first time using data from the Compact Array, Cendes began by replicating previously-published images that used data from the same telescope.

She then produced her own images by analyzing the datasets used, comparing them to the published images, and refining her technique until her images resembled the published ones.

After becoming proficient in data-to-image translation, Cendes analyzed the 25-year dataset from the radio telescope in full.

While previous researchers had analyzed parts of the dataset, Cendes said that she was “the first person to go back and really see this entire stretch of time.”

New planetarium in the works at UTSG

The world-class facility will provide unparalleled access to the cosmos

New planetarium in the works at UTSG

The Department of Astronomy & Astrophysics is planning to replace the current Astronomy & Astrophysics Building with a new structure that includes a planetarium, which could become a tourist and cultural centrepiece in Toronto. 

The proposed construction is at 50 St. George Street, where the facility is currently located. 

According to Raymond Carlberg, Chair of the Department of Astronomy & Astrophysics, the new planetarium will seat around 150 people, six times more than the 25-person capacity of the department’s current planetarium. Blueprints for the planetarium could be finalized as early as 2020.

The planetarium attracts students and the general public for its shows like the Grand Tour of the Cosmos and The Life and Death of Stars, which are usually led by U of T graduate students. 

However, the current theatre has limitations. 

It is not wheelchair-accessible, and requires patrons to plan early to avoid the dreaded ‘bad seats,’ where catching a glimpse of the stars comes with a side of neck tension. 

According to Carlberg, the new planetarium would also improve pedagogy.  

“In Canada, most of the planetariums are in things like the Ontario Science Centre — but they don’t have an academic use there,” said Carlberg. “We’re not looking to do what Ontario Science Centre does, which is orient it to the public at large. We’re interested in giving students the best possible education.” 

In addition to providing one-of-a-kind learning opportunities for their students, the department hopes that the new planetarium will be a forum for reconciliation and Indigenous education.  

“Indigenous people… have a sky lore of their own,” explained Carlberg. 

“We have a sky lore with our Greek and Roman constellations and they have theirs. In fact, there [are] several, for different native communities across North America because they each have their own stories. So that’s a thing we would like to do, is reach out to folks and to try to help them succeed within the University of Toronto.”

The department is now in the ‘idea stage’ of the design process. Since the current Astronomy & Astrophysics Building would have to be demolished to build the planetarium, there is discussion over other potential features of the building including an observatory, faculty offices, and teaching labs. 

Though details are sparse, the department hopes  that the new facility will be an architectural landmark whose purpose goes beyond the scope of astronomy, from visualizing climate data to exploring the neural networks of the human brain. 

The ultimate guide to watching meteor showers

Here’s how you can wish upon a shooting star this year

The ultimate guide to watching meteor showers

Despite being pieces of space debris, meteors put on a magnificent display when they enter Earth’s atmosphere, decorating the night sky with vivid colours of blues, greens, yellows and reds. Whether you are an avid meteor shower watcher or a first-time goer, here are tips to help you catch a better glimpse of Earth’s rocky visitors.

Where do I go?

Although this may come as a surprise, it is actually not very difficult to find a good location to view meteor showers. Just keep in mind the following points when hunting for your spot of the night:

Look for an open area like a field or a park. Steer clear of places where your view of the sky is obstructed by buildings, trees, or other tall objects.

Make sure it’s dark enough. City lights can be a huge distraction and take away from the visibility of the meteors. Department of Astronomy and Astrophysics Associate Professor Michael Reid recommends that you refrain from looking at your phone. “Your eyes take about ten minutes to fully adapt to darkness,” said Reid. “If you look at a cell phone screen or streetlight even briefly, you’ll degrade your night vision.”

How do I prepare?

You don’t need any fancy equipment to view this celestial event. However, the following tips can make your viewing experience more pleasant:

Grab a lawn chair. Keeping your eyes on the skies so you don’t miss a single second of stars shooting across the darkness requires a lot of upwards gazing. Bring a chair or a blanket to spread on the ground so you can do so in comfort.

Pack bug spray and a jacket. Summer nights spent outdoors entails mosquitoes and other little critters. Stay bite-free with bug spray and have a light jacket to throw on when it gets chilly.

Gather your friends. “Meteor watching requires patience, so it is a great chance to pick out constellations in the sky,” said Professor Raymond Carlberg, Chair of the Department of Astronomy and Astrophysics. Having your friends to share the moment can make wait times between meteor fly-bys a lot more entertaining. You could try to spot stars or play a round of astronomy trivia.

Check the weather. Nothing can be worse than a rainwstorm on the night you scheduled your outing, or the moon outshining all the meteors in your area. Be sure to check the weather and location of the moon prior to making your trip.

When is the next meteor shower?

Now that you’re ready to go, be on the lookout for more accurate predictions of the best times to catch each of these events. Meteor showers typically occur over the span of a couple of days, so if you miss the days listed below, try your luck another time. The International Meteor Organization also has a detailed calendar of upcoming meteor showers.

October 21 – peak for the Orionids showers

November 17 – peak for the Leonids showers

December 13 – peak for the Geminids showers

Happy meteor shower watching!

A day — or millennium — in the life of a star

PhD candidate Alysa Obertas hosts Life and Death of Stars planetarium show

A day — or millennium — in the life of a star

It is truly a shame that light pollution prevents Torontonians from gazing at the stars because, as Alysa Obertas demonstrates, they are some of the most beautiful objects in all of existence. Admittedly, stars being beautiful isn’t exactly news. But Obertas, a PhD candidate with U of T’s Department of Astronomy & Astrophysics, breathes new life into this tired cliché in the brilliant planetarium show Life and Death of Stars.

Originally created by U of T astrophysicist and Outreach Coordinator of the Department of Mathematics Dr. Ilana MacDonald, the show is presented in the basement planetarium of the Astronomy & Astrophysics Building. Life and Death of Stars opens with a sweeping view of the Toronto skyline, familiarly devoid of stars and overwhelmingly polluted by the glaring city lights. Obertas soon shows us city dwellers what we’ve been missing by transforming a murky screen into a majestic illumination of the skies outside the city.

From there, the audience is brought on a voyage from the surface of our planet into the sprawling grounds of the cosmos. Moving from one celestial object to another, Obertas meticulously explains each astrophysical concept and fundamental law governing the birth, life, and death of stars. Notable curiosities like the red supergiant Betelgeuse and goldmine supernova SN1987A are given special attention, with their unusual traits fully exposed via high-resolution images on-screen, and a comprehensive commentary given by Obertas off-screen.

“One thing I hope audiences take away is that stars aren’t fixed they change and evolve throughout their lifetimes,” wrote Obertas in an email to The Varsity. “Even more incredible is that as stars evolve and eventually end their lives, they create heavier elements. This material gets mixed back into surrounding clouds of gas, which new stars and planets form out of. We wouldn’t be here on Earth if it weren’t for dead stars.”

It is important to note that the experience is not at all a tedious lecture. No physics foreknowledge is required; Obertas explains everything clearly, concisely, and without technobabble. In fact, portions of the presentation have little to do with astrophysics at all as they focus on constellations and what can be seen with the naked eye. Dazzling visuals that fill the room delight children and adults, alike. “I hope that people who are curious about science, space, and astronomy attend the shows and leave with a new perspective and appreciation for our place in the universe,” said Obertas. “You don’t need to be an expert to appreciate the cosmos we all share the night sky.”

Altogether, Obertas deftly weaves astronomy with entertainment to create an experience accessible for all educational backgrounds and recommendable for all ages. Obertas’ stunning visuals and eloquent descriptions are an excellent primer for anyone seeking a comfortable introduction to the cosmos. In both the literal and the metaphorical sense, the show is absolutely stellar.

The show is roughly an hour long and costs $10 per person. More information can be found here.

We are all #UnitedByTheStars

New planetarium series from the Dunlap Institute to deliver aid to Syrian refugees

We are all #UnitedByTheStars

With Canada welcoming approximately 25,000 Syrian refugees this year, U of T is full of exciting student initiatives to raise funds that will help landed refugees resettle. These initiatives include a special series of planetarium shows, organized by graduate students, Jielai Zhang and Pegah Salbi of the University of Toronto, Department of Astronomy and Astrophysics. The show is called “Astronomy’s Golden Age,” and the students intend to give 100 per cent of the proceeds from ticket sales to Red Cross Canada. The Varsity sat down with Zhang and Salbi to discuss the upcoming series.

The Varsity (TV): How did you come up with this idea?

Jielai Zhang and Pegah Salbi: We had been watching the news and heard about this huge problem about people being displaced both in Syria and to the neighbouring regions. There were all these problems about people not having enough food to eat or places to stay and everyone was helping to solve this issue. So we thought that we should do something to help them too. We thought that there is a planetarium in our department, and we should use astronomy to educate people and at the same time, they can do good too by supporting Syrian refugees. We set a target for raising $10,000 and we are already at 20 per cent [of that amount].

TV: When you first came up with this idea, how did the department respond?

Zhang and Salbi:We first pitched this idea to the graduate students, because we wanted to see what the response would be, and also because we couldn’t do all the shows and advertisement by ourselves. The response was phenomenal and very positive. All the people in the department also helped us to take care of the financial and administrative aspect.

TV: What is the show about?

Zhang and Salbi: We wanted to relate the show somehow to the cause that we’re trying to raise money for. One of our colleagues gave us an idea of representing Islamic contributions to astronomy so we can relate the show to Syria. There are a lot of connections between modern-day astronomy and Islamic astronomy. For example, a lot of the stars’ names are derived from Arabic. Astronomers present our planetarium shows, and they start from Earth and can travel to different planets, etc. The room is a black dome, and it can simulate the night sky.

TV: Why did you choose to support Red Cross Canada?

Zhang and Salbi: Red Cross has many programs designed to help refugees, and we were interested in two of them. One of them is focused on internally displaced Syrians as well as refugees in neighbouring countries, and the money directly goes to buying them food, emergency kits, medication, water, and basic survival needs. The other program helps Syrian refugees coming to Canada resettle smoothly and help them transition into the Canadian culture. The reason we picked Red Cross was because it is one of the most efficient organization[s] in terms of providing food, healthcare and shelter. Ninety-five per cent of the funds go directly to helping the Syrians. In total, we have scheduled 24 shows up to March. Each show holds 26 people.

TV: What was your favourite part about organizing the shows?

Zhang and Salbi: Our favourite part was the enthusiasm and positive energy we received from the department to pursue our idea. We have four people who [have] worked endlessly to formulate the presentation[…] We have been working on this project for the past two months, [and] about 30 people have been a part of this process.

TV: Do you have anything else you’d like to say to the readership?

Zhang and Salbi: As an endnote, we want to pose a challenge for the rest of the U of T community to support the Syrian refugees in any way possible. We, as astronomers, are teaching about astronomy so we want to see what other departments and faculties can do to support the refugees. By investing in their health and well-being, they will become resettled in Canada, and they will gain knowledge and may advance the field of science. The stars unite us all, and humanity should too.

The series will be held at the planetarium at 50 St George St. Tickets are $10; the first show is scheduled for January 22 and the second for January 28.