universe Archives - News@91��ɫ

Webb reveals a galaxy sparkling with the universe’s oldest star clusters

sandramc — Thu, 29 Sep 2022 15:16:39 +0000

TORONTO, Sept. 29, 2022 – Using the James Webb Space Telescope (JWST), researchers from the CAnadian NIRISS Unbiased Cluster Survey (CANUCS) team, including 91��ɫ, have identified the most distant globular clusters ever discovered. These dense groups of millions of stars may be relics that contain the first and oldest stars in the universe.

The early analysis of Webb’s First Deep Field image, which depicts some of the universe’s earliest galaxies, is published today in .

Adam Muzzin

“Globular clusters are quite mysterious. They orbit the Milky Way and other galaxies, however, we have little idea where they come from,” says study co-author Associate Professor Adam Muzzin of 91��ɫ’s Faculty of Science. “With the James Webb Space Telescope, we were able to see incredibly far into the past, much farther than we’ve ever been able to see before — and what we saw was spectacular.”

Ghassan Sarrouh

91��ɫ PhD student Ghassan Sarrouh, also a co-author on the research, says “In this case, we were able to identify several globular clusters, collections of ancient stars, far beyond our Milky Way some nine billion light years away when the universe was about a third of its current age. It’s a really exciting and significant finding.”

The research team looked at one galaxy in particular to understand what was happening around it.

“JWST was built to find the first stars and the first galaxies and to help us understand the origins of complexity in the universe, such as the chemical elements and the building blocks of life,” says Lamiya Mowla, Dunlap Fellow at the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto and co-lead author of the study. “This discovery in Webb’s First Deep Field is already providing a detailed look at the earliest phase of star formation, confirming the incredible power of JWST.”

In the finely detailed Webb’s First Deep Field image, the researchers zeroed in on what they’ve dubbed “the Sparkler galaxy,” which is nine billion light years away. This galaxy got its name for the compact objects appearing as small yellow-red dots surrounding it, referred to by the researchers as “sparkles.” The team posited that these sparkles could either be young clusters actively forming stars — born three billion years after the Big Bang at the peak of star formation — or old globular clusters. Globular clusters are ancient collections of stars from a galaxy’s infancy and contain clues about its earliest phases of formation and growth.

From their initial analysis of 12 of these compact objects, the researchers determined that five of them are not only globular clusters but among the oldest ones known.

This illustration shows a phenomenon known as gravitational lensing, which is used by astronomers to study very distant and very faint galaxies. Note that the scale has been greatly exaggerated in this diagram. In reality, the distant galaxy is much further away and much smaller. Lensing clusters are clusters of elliptical galaxies whose gravity is so strong that they bend the light from the galaxies behind them. This produces distorted, and often multiple images of the background galaxy. But despite this distortion, gravitational lenses allow for greatly improved observations as the gravity bends the light’s path towards Hubble, amplifying the light and making otherwise invisible objects observable. A team of astronomers has used Abell 383, one such gravitational lens, to observe a distant galaxy whose light is resolved into two images by the cluster. The gravitational lensing effect means that astronomers have been able to determine fascinating insights about the galaxy that would not normally be visible even with Hubble or large ground-based telescopes. Among their discoveries is that the distant galaxy’s stars are very old, meaning that galaxies probably formed earlier in cosmic history than we first thought.

“Looking at the first images from JWST and discovering old globular clusters around distant galaxies was an incredible moment, one that wasn’t possible with previous Hubble Space Telescope imaging,” says Kartheik G. Iyer, Dunlap Fellow at the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto and co-lead author of the study. “Since we could observe the sparkles across a range of wavelengths, we could model them and better understand their physical properties, like how old they are and how many stars they contain. We hope the knowledge that globular clusters can be observed at from such great distances with JWST will spur further science and searches for similar objects.”

The Milky Way galaxy has about 150 globular clusters, and how and when exactly these dense clumps of stars formed is not well understood. Astronomers know that globular clusters can be extremely old, but it is incredibly challenging to measure their ages. Using very distant globular clusters to age-date the first stars in distant galaxies has not been done before and is only possible with JWST.

Until now, astronomers could not see the surrounding compact objects of the Sparkler galaxy with the Hubble Space Telescope (HST). This changed with JWST's increased resolution and sensitivity, unveiling the tiny dots surrounding the galaxy for the first time in Webb’s First Deep Field image. The Sparkler galaxy is special because it is magnified by a factor of 100 due to an effect called gravitational lensing — where the SMACS 0723 galaxy cluster in the foreground distorts what is behind it, much like a giant magnifying glass. Moreover, gravitational lensing produces three separate images of the Sparkler, allowing astronomers to study the galaxy in greater detail.

“Our study of the Sparkler highlights the tremendous power in combining the unique capabilities of JWST with the natural magnification afforded by gravitational lensing,” says CANUCS team lead Chris Willott from the National Research Council’s Herzberg Astronomy and Astrophysics Research Centre. “The team is excited about more discoveries to come when JWST turns its eye on the CANUCS galaxy clusters next month.”

The researchers combined new data from JWST’s Near-Infrared Camera (NIRCam) with HST archival data. NIRCam detects faint objects using longer and redder wavelengths to observe past what is visible to the human eye and even HST. Both magnifications due to the lensing by the galaxy cluster and the high resolution of JWST are what made observing compact objects possible.

The Canadian-made Near-Infrared Imager and Slitless Spectrograph (NIRISS) instrument on the JWST provided independent confirmation that the objects are old globular clusters because the researchers did not observe oxygen emission lines — emissions with measurable spectra given off by young clusters that are actively forming stars. NIRISS also helped unravel the geometry of the triply lensed images of the Sparkler.

JWST will observe the CANUCS fields starting in October 2022, leveraging JWST data to examine five massive clusters of galaxies, around which the researchers expect to find more such systems. Future studies will also model the galaxy cluster to understand the lensing effect and execute more robust analyses to explain the star formation histories.

Collaborating institutions include Saint Mary’s University and institutions in the United States and Europe. The research was supported by the Canadian Space Agency and the Natural Sciences and Engineering Research Council of Canada.

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91��ɫ is a modern, multi-campus, urban university located in Toronto, Ontario. Backed by a diverse group of students, faculty, staff, alumni and partners, we bring a uniquely global perspective to help solve societal challenges, drive positive change and prepare our students for success. 91��ɫ's fully bilingual Glendon Campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education. 91��ɫ’s campuses in Costa Rica and India offer students exceptional transnational learning opportunities and innovative programs. Together, we can make things right for our communities, our planet, and our future.

Media Contact:

Sandra McLean, 91��ɫ Media Relations, 416-272-6317, sandramc@yorku.ca

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$3M investment at 91��ɫ U will bring wonders of universe to more students, wider public

roshanp — Tue, 07 Aug 2018 14:17:24 +0000

TORONTO, Tuesday, Aug. 7, 2018 – 91��ɫ will expand its astronomy outreach and teaching to communities across Canada with the help of a new $1.5-million gift matched by the University for a total of $3 million. 91��ɫ U will announce the details of this initiative, believed to be the first of its kind in North America, Thursday, Aug. 9.

Media are invited to hear first-hand what the new matched gift will allow the University to achieve in the way of astronomy outreach and the excitement it hopes to build in the wonders of the Universe.

WHAT: 91��ɫ announcement of endowed Chair

WHEN: Thursday, Aug. 9 at 9:30am

WHO:

Rhonda Lenton, President & Vice-Chancellor
Ray Jayawardhana, Dean, Faculty of Science
Allan Carswell, Carswell Family Foundation
Jeff O’Hagan, VP Advancement
Paul Delaney, University Professor, Faculty of Science

WHERE: Lobby of Life Sciences Building, Keele campus, 91��ɫ, (number 90 on the .)

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About 91��ɫ
is known for championing new ways of thinking that drive teaching and research excellence. Our students receive the education they need to create big ideas that make an impact on the world. Meaningful and sometimes unexpected careers result from cross-discipline programming, innovative course design and diverse experiential learning opportunities. 91��ɫ students and graduates push limits, achieve goals and find solutions to the world’s most pressing social challenges, empowered by a strong community that opens minds. 91��ɫ U is an internationally recognized research university – our 11 faculties and 26 research centres have partnerships with 200+ leading universities worldwide. Located in Toronto, 91��ɫ is the third largest university in Canada, with a strong community of 53,000 students, 7,000 faculty and administrative staff, and more than 300,000 alumni. 91��ɫ U's fully bilingual Glendon campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education.

Media Contact:

Sandra McLean, 91��ɫ Media Relations, 416-736-2100 ext. 22097, sandramc@yorku.ca

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Unravel the mysteries of the universe with 91��ɫ U scientists

roshanp — Tue, 10 Oct 2017 19:29:21 +0000

TORONTO, Tuesday, October 10, 2017 – 91��ɫ scientists will share secrets of the universe, a vast and mysterious place that pushes the boundaries of imagination, at the Faculty of Science and Toronto Public Library speaker series.

Watch / share video: https://youtu.be/zYU6CXz_mS4

The series will run from Oct. 11 to Nov. 14 with speakers talking about everything from quasars and dark matter to the possibility of life on another planet.

Quasar, Quasar, Burning Bright, Oct. 11, from 6:30 to 7:30pm,
Professor Patrick Hall of the Faculty of Science talking about the brightest objects in our Universe, how they are formed and how they tap the strong gravity of black holes. Quasars contain rotating disks as big as our solar system and hotter than the Sun.
How to Get to Mars, Oct. 12, from 6:30 to 7:30pm,
For decades, NASA has been sending orbiters, landers and rovers to Mars and other planets within our solar system for research and exploration, providing a window onto strange new worlds. Professor John Moores of the Lassonde School of Engineering will provide an overview of our past, present and future planetary exploration mission.
The Social Habits of Galaxies, Oct. 17, from 7 to 8pm, & Nov. 16, from 7 to 8pm,
Most galaxies enjoy the company of other galaxies and organize into various shapes known as the “cosmic web.” Many of them also like to spin. PhD student George Conidis of the Faculty of Science, will examine copies our own galaxy, The Milky Way, and its friends to better understand the social habits of disk galaxies and how they spin.
The Secrets of Our Dark Universe, Nov. 11, from 2 to 3pm,
Most of our Universe is made up of dark matter and dark energy, but so far scientists have had a hard time detecting or explaining them. PhD student Alexandra Terrana of the Faculty of Science will explore some of the big open questions in cosmology, what dark matter and energy are, and how an alternative theory of gravity might solve these mysteries.
Is Anyone Home? Nov. 14, from 6:30 to 7:30pm,
Since 1995 thousands of planets have been detected orbiting other stars. Many of these worlds could possibly contain liquid water and even life. Professor Paul Delaney of the Faculty of Science will describe our current understanding of exoplanets, the ongoing search for them and the implications for the search for life.

Watch / share video:

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is known for championing new ways of thinking that drive teaching and research excellence. Our students receive the education they need to create big ideas that make an impact on the world. Meaningful and sometimes unexpected careers result from cross-discipline programming, innovative course design and diverse experiential learning opportunities. 91��ɫ students and graduates push limits, achieve goals and find solutions to the world’s most pressing social challenges, empowered by a strong community that opens minds. 91��ɫ U is an internationally recognized research university – our 11 faculties and 26 research centres have partnerships with 200+ leading universities worldwide. Located in Toronto, 91��ɫ is the third largest university in Canada, with a strong community of 53,000 students, 7,000 faculty and administrative staff, and more than 295,000 alumni. 91��ɫ U's fully bilingual Glendon campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education.

Media Contacts:

Sandra McLean, 91��ɫ Media Relations, 416-736-2100 ext. 22097, sandramc@yorku.ca

The post Unravel the mysteries of the universe with 91��ɫ U scientists appeared first on News@91��ɫ.