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This new space telescope should show us what the universe looked like as a baby – WPRL

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Imagine knowing nothing about your childhood, nothing about where you came from, and spending years hunting for the answers. Then someone hands you a just-discovered trove of photographs of yourself as an infant. You’d finally be able to scrutinize every detail, searching for clues about yourself and how you came to be the way you are.

That’s just what it will be like for astronomers once a long-anticipated, $10 billion telescope finally blasts off into space in the coming days. If all goes well, it will soon show them what the universe looked like as a newborn, nearly 14 billion years ago.

NASA’s James Webb Space Telescope, the most powerful space telescope ever, is waiting at a launch site in French Guiana. It should be able to detect infrared light from galaxies that are so far away that the light from them has been traveling through space for almost the entire history of the universe.

That means when astronomers detect light from these stars and galaxies, it will be like receiving snapshots in time from the distant past.

“We are trying to build up the story of how the first galaxies ever emerged and how those evolved into galaxies we see today and we live in today,” says Maruša Bradač, an astronomer at the University of California, Davis. “If you don’t get the beginning right, it’s really difficult to figure out what the whole evolution looked like.”

A telescope, or a time machine?

The Milky Way Galaxy is humanity’s home sweet home, but the universe contains hundreds of billions, if not trillions of other galaxies.

“The Andromeda Galaxy is the closest big galaxy to ours. You can even see it with the naked eye, which is kind of cool,” says Bradač. “When you look at that galaxy, you see it as it was 2.2 million years ago.”

That’s because it takes 2.2 million years for light to travel all the way from the Andromeda Galaxy to Earth.

Using telescopes, astronomers have been able to see far more distant galaxies, which means they’ve been able to see farther back into the universe’s history. So far, the most distant galaxy ever discovered, GN-z11, was spotted by the Hubble Space Telescope.

To the untrained eye, it looks like a red blob, but “it’s basically like looking back in time about 13.3, 13.4 billion years ago,” says Charlotte Mason, associate professor at the Cosmic Dawn Center of the Niels Bohr Institute and the University of Copenhagen. “That’s just 300, 400 million years after the Big Bang.”

Hubble is limited in how far back in time it can look, so finding this galaxy was kind of a lucky break. Astronomers only spotted it because decades of using Hubble have let them scour much of the sky, and this particular early galaxy is surprisingly bright.

“It’s potentially more massive or is forming stars much more quickly than most theoretical models would predict,” says Mason. “Already, with that one galaxy, we’ve started to question some of our assumptions about how galaxies evolve.”

The James Webb Space Telescope should be able to provide more information about lots of additional galaxies this old and even older, which will help researchers understand how galaxies formed and changed into the familiar shapes and structures seen today.

“We really need much better samples, we need many more galaxies, and we need to step back in time to see how the galaxies are growing,” says Garth Illingworth, an astronomer with the University of California, Santa Cruz.

The James Webb Space Telescope has technology that should let it see back to 100 million to 200 million years after the Big Bang.

“So really, the period when we think the very first galaxies formed,” says Mason.

This telescope, which took decades to design and build, also has instruments that will let scientists probe the chemical make-up of the galaxies.

Watching the earliest stars in the universe explode

The holy grail for scientists who study the early universe is to find light from the very first galaxy, or the very first stars, says Mason. Those first stars would have formed from the elements created by the Big Bang, mainly helium and hydrogen.

“They set the stage for all of the subsequent galaxy and star formation,” says Mason. “They really fundamentally changed their surroundings.”

The odds of seeing those stars with the James Webb Space Telescope, however, are small. “There’s maybe even more of a chance that we might see one of those stars explode,” says Mason.

Those explosions would have spewed out other chemical elements forged in the earliest stars, setting the universe on a course where carbon, oxygen and other elements ultimately became the building blocks of life.

Illingworth believes that the James Webb Space Telescope won’t be able to see the very first star ever.

“That’s just practically impossible,” he says, adding that even the first little growing galaxies with just a few stars also aren’t likely to be detected.

“But we will go back to the point where we really start to see the galaxies at a very early stage, so that we can trace the whole history, essentially, from then, 200 million years after the Big Bang, through to now,” says Illingworth. “That’s what’s amazing about a telescope like this.”

Humans have long looked up at the skies and tried to make sense of our place in the universe, Mason points out, and the James Webb Space Telescope is the latest step forward in that ancient quest.

“How did we get here? What is the history of our universe that brought us to the point where we can sit here and think about it?” she asks. “To me, that really means starting at the beginning. How did the very first galaxies form in our universe? Because those are really the building blocks of the Milky Way that we live in.”

Copyright 2021 NPR. To see more, visit https://www.npr.org.

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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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