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Halifax researcher to study 'baby galaxies' using new space telescope – CBC.ca

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A space telescope launching next week will carry with it the hopes and dreams of a Halifax researcher Marcin Sawicki, who helped develop an instrument on board.

The telescope will be able to take pictures of the first stars that appeared in the universe after the Big Bang.

The James Webb Space Telescope is scheduled to launch on Dec. 24 at the earliest from the spaceport in French Guiana in South America.

Marcin Sawicki is a professor in the department of astronomy and physics at Saint Mary’s University. (Submitted by Marcin Sawicki)

The telescope, the size of a school bus while it’s nestled in the nose of the rocket, will unfurl to the size of a tennis court once it reaches its final destination about 1.5 million kilometres from Earth — five or six times the distance to the moon.

The telescope is so sensitive it will be able to capture images of what the first stars in the universe looked like about 13.5 billion years ago. That’s how long it has taken for the light to reach us.

“When the universe came out of the Big Bang, there were no stars, no galaxies, no light,” said Sawicki, a professor in the department of astronomy and physics at Saint Mary’s University and the director of the Institute for Computational Astrophysics. “It was a very, very, very dark place.

“We expect that the first stars started turning on in the very first galaxies. And so Webb is built to find, to detect these very, very first sources of light — cosmic dawn, as we like to say.”

For the past 20 years, Sawicki has been involved in the development of an instrument called NIRISS — Near Infrared Imager and Slitless Spectrograph — that will be on board the telescope.

The device will make it possible to detect very distant galaxies and exoplanets, or planets that orbit around stars outside our solar system.

NIRISS splits the light from everything in its field of view into a spectrum, like a rainbow, Sawicki said. By looking at the intensity of the different colours, the scientists will be able to tell how far away an object is.

The primary mirror of NASA’s James Webb Space Telescope is deployed at NASA’s Goddard Space Flight Center in Greenbelt, Md. (NASA/Desiree Stover)

The spectrograph is one of two Canadian-built instruments on board the telescope, along with a fine guidance sensor, which will allow the telescope to remain locked on a specific target.

Because of Sawicki’s involvement, he and his team will have exclusive access to some of the telescope’s data for one year.

100 times stronger than Hubble

The Webb telescope is about 100 times more powerful than its predecessor, the Hubble, which can capture light from about 12 billion years ago. The difference between what those early galaxies — what Sawicki calls “baby galaxies” — look like from Hubble and what they’ll look like from Webb is immense, he said.

“It’s sort of the difference between seeing newborn babies and seeing toddlers, you know, kids in kindergarten. That’s a huge difference.”

This color-composite mosaic of the central part of the Orion Nebula is based on 81 images from the European Southern Observatory (ESO) Very Large Telescope at the Paranal Observatory in Chile. Researchers will train Webb on this region to study phenomena associated with the birth of stars and planets. (ESO/M.McCaughrean)

Sawicki said he thinks it’s important to learn more about the early galaxies because they contain the history of Earth and every human being on it.

“Those stars, like our sun, contain a lot of chemical elements that were made in earlier generations of stars. And so every chemical element in your body, except for hydrogen has been made in a star,” he said.

“It’s our history, it’s our past, it’s our origins. That’s the exciting thing about it, looking back into the past to see where we come from.”

This image from the Hubble telescope shows the heart of the globular star cluster Messier 92 (M92), which packs roughly 330,000 stars together and is one of the oldest and brightest in the Milky Way. Webb will observe M92, or a similar globular cluster, early in its mission to demonstrate its ability to distinguish the light of its individual stars in a densely packed environment. (NASA/ESA/Gilles Chapdelaine)

In addition to showing what the early galaxies looked like, the telescope will help scientists understand how galaxies grow over time, Sawicki said.

“What kind of physical changes happen in them? How quickly do they build up their bodies, their mass, assemble new stars, produce these chemical elements?”

Once the Webb telescope arrives at its destination, it will go through a series of tests before starting to send data in about six months.

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Consistent Asteroid Collisions Rock Previous Thinking on Mars Impact Craters – SciTechDaily

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This image provides a perspective view of a triple crater in the ancient Martian highlands. Credit: ESA/DLR/FU Berlin

New Curtin University research has confirmed the frequency of asteroid collisions that formed impact craters on <span aria-describedby="tt" class="glossaryLink" data-cmtooltip="

Mars
Mars is the second smallest planet in our solar system and the fourth planet from the sun. Iron oxide is prevalent in Mars’ surface resulting in its reddish color and its nickname "The Red Planet." Mars’ name comes from the Roman god of war.

“>Mars has been consistent over the past 600 million years.

New Curtin University research has confirmed the frequency of asteroid collisions that formed impact craters on Mars has been consistent over the past 600 million years.

The study, published in Earth and Planetary Science Letters, analyzed the formation of more than 500 large Martian craters using a crater detection algorithm previously developed at Curtin, which automatically counts the visible impact craters from a high-resolution image.

Despite previous studies suggesting spikes in the frequency of asteroid collisions, lead researcher Dr. Anthony Lagain, from Curtin’s School of Earth and Planetary Sciences, said his research had found they did not vary much at all for many millions of years.

Impact Craters on Mars

One of the 521 large craters that has been dated in the study. The formation age of this 40km crater has been estimated using the number of small craters accumulated around it since the impact occurred. A portion of these small craters are shown on the right panel and all of them have been detected using the algorithm. In total, more than 1.2 million craters were used to date the Martian craters. Credit: Curtin University

Dr. Lagain said counting impact craters on a planetary surface was the only way to accurately date geological events, such as canyons, rivers, and volcanoes, and to predict when, and how big, future collisions would be.

“On Earth, the erosion of plate tectonics erases the history of our planet. Studying planetary bodies of our Solar System that still conserve their early geological history, such as Mars, helps us to understand the evolution of our planet,” Dr. Lagain said.

“The crater detection algorithm provides us with a thorough understanding of the formation of impact craters including their size and quantity, and the timing and frequency of the asteroid collisions that made them.”

Past studies had suggested that there was a spike in the timing and frequency of asteroid collisions due to the production of debris, Dr. Lagain said.

“When big bodies smash into each other, they break into pieces or debris, which is thought to have an effect on the creation of impact craters,” Dr. Lagain said.

“Our study shows it is unlikely that debris resulted in any changes to the formation of impact craters on planetary surfaces.”

Co-author and leader of the team that created the algorithm, Professor Gretchen Benedix, said the algorithm could also be adapted to work on other planetary surfaces, including the Moon.

“The formation of thousands of lunar craters can now be dated automatically, and their formation frequency analyzed at a higher resolution to investigate their evolution,” Professor Benedix said.

“This will provide us with valuable information that could have future practical applications in nature preservation and agriculture, such as the detection of bushfires and classifying land use.”

Reference: “Has the impact flux of small and large asteroids varied through time on Mars, the Earth and the Moon?” by Anthony Lagain, Mikhail Kreslavsky, David Baratoux, Yebo Liu, Hadrien Devillepoix, Philip Bland, Gretchen K. Benedix, Luc S. Doucet and Konstantinos Servis, 7 January 2022, Earth and Planetary Science Letters.
DOI: 10.1016/j.epsl.2021.117362

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B.C. researchers uncover mechanism that keeps large whales from drowning while feeding on krill – CTV News Vancouver

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Vancouver –

New research from the University of British Columbia is shedding light on the ways that whales feed underwater without flooding their airways with seawater.

The research, published this month in Current Biology, shows that lunge-feeding whales – the type that lunge and gulp at large schools of krill – have a special mechanism in the back of their mouths that stops water from entering their lungs when eating.

“It’s kind of like when a human’s uvula moves backwards to block our nasal passages, and our windpipe closes up while swallowing food,” says lead author Dr. Kelsey Gil, a postdoctoral researcher in the department of zoology, in a statement.

Specifically, a fleshy bulb acts as a plug, to close off upper airways, while a larynx closes to block lower airways.

The humpback whale and the blue whale are both lunge-feeders, but the scientists’ research focused on fin whales, thanks in part to being able to travel to Iceland in 2018 and examine carcass remains at a commercial whaling station.

“We haven’t seen this protective mechanism in any other animals, or in the literature. A lot of our knowledge about whales and dolphins comes from toothed whales, which have completely separated respiratory tracts, so similar assumptions have been made about lunge-feeding whales,” Gil said.

Lunge-feeders are impressive, Gil said, because sometimes the amount of food and water they consume is larger than their bodies. After snapping at krill, and while blocking the water from their airways, the whales then drain the ocean water through their baleen, leaving behind the tasty fish.

The study’s senior author Dr. Robert Shadwick, a professor in the UBC department of zoology, says the efficiency of the whales’ feeding is a key factor in their evolution.

“Bulk filter-feeding on krill swarms is highly efficient and the only way to provide the massive amount of energy needed to support such a large body size. This would not be possible without the special anatomical features we have described,” he said in a statement. 

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Study confirmed the frequency of asteroid collisions that formed Mars craters – Tech Explorist

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Mapping and counting impact craters are the most commonly used technique to derive detailed insights on geological events and processes shaping the surface of terrestrial planets. Scientists from Curtin University have used a crater detection algorithm to analyze the formation of more than 500 large Martian craters.

The algorithm they used automatically counts the visible impact craters from a high-resolution image. Scientists found that the frequency of asteroid collisions that formed Mars craters has been consistent for over 600 million years.

Lead scientist Dr. Anthony Lagain from Curtin’s School of Earth and Planetary Sciences said, “Despite previous studies suggesting spikes in the frequency of asteroid collisions, this research had found they did not vary much at all for many millions of years.”

“Counting impact craters on a planetary surface was the only way to accurately date geological events, such as canyons, rivers, and volcanoes, and to predict when, and how big, future collisions would be.”

“On Earth, the erosion of plate tectonics erases the history of our planet. Studying planetary bodies of our Solar System that still conserve their early geological history, such as Mars, helps us to understand the evolution of our planet.”

“The crater detection algorithm provides us with a thorough understanding of the formation of impact craters, including their size and quantity, and the timing and frequency of the asteroid collisions that made them.”

“Past studies had suggested that there was a spike in the timing and frequency of asteroid collisions due to the production of debris.”

“When big bodies smash into each other, they break into pieces of debris, which is thought to affect the creation of impact craters.”

“Our study shows it is unlikely that debris resulted in any changes to the formation of impact craters on planetary surfaces.”

Co-author and leader of the team that created the algorithm, Professor Gretchen Benedix, said“the algorithm could also be adapted to work on other planetary surfaces, including the Moon.”

“The formation of thousands of lunar craters can now be dated automatically, and their formation frequency analyzed at a higher resolution to investigate their evolution.”

“This will provide us with valuable information that could have future practical applications in nature preservation and agriculture, such as the detection of bushfires and classifying land use.”

Journal Reference:

  1. Anthony Lagain et al. Has the impact flux of small and large asteroids varied through time on Mars, the Earth, and the Moon? DOI: 10.1016/j.epsl.2021.117362

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