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Victoria astronomer helps discover 10 billion-year-old galaxy cluster – Victoria News

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A Victoria astronomer is amongst a group of international researchers responsible for capturing the clearest image to date of a space scene from a long time ago in a galaxy far, far away… 10 billion years away, to be exact.

Using high-powered telescopes, University of Victoria astronomer Jon Willis and his colleagues discovered a 10 billion-year-old galaxy cluster. Willis, who is the lead author of the group’s research, published in the science journal Nature, says a galaxy cluster can be likened to “a great city of galaxies,” though galaxies themselves are “collections of billions of stars all held together by gravity.”

Researching the stars that compose galaxies help researchers determine how old they are and when they formed, Willis says. In a media release, the University of Victoria says the recent discovery “provides clues the universe was more evolved than previously thought.”

READ ALSO: UVic astronomers help discover new planet

A composite image of the galaxy cluster XLSSC 122 using images from the Hubble Space Telescope and European Southern Observatory’s Very Large Telescope. (Photo by Jon Willis).

Willis likens the discovery to finding a Rosetta Stone.

“We’ve discovered what is the most ancient city of galaxies in the universe. It’s the clearest snapshot yet of a galaxy cluster,” he says. “The Rosetta Stone was a glimpse into ancient Egyptian history, this discovery provides clues to understanding the physics of what was going on in that environment billions of years ago.”

Willis says researchers were surprised to find a galaxy cluster so early in the universe’s development. The cluster, at 10 billions years old, is an old object in a young (13-billion-year-old) universe.

“It’s an equivalent of meeting a child who displays all the characteristics of an adult,” Willis says. “We have met these young clusters – think the universe was just over three billion years old – so we’ve found it’s quite a precocious object and it can teach us about how physics works in the early universe.”

The powerful, prominent images of the cluster were taken from the Hubble Space Telescope and European Southern Observatory’s Very Large Telescope. A number of other telescopes were used to get to the discovery, Willis says.

The research group, which includes scientists from Denmark, Canada and the U.S., will likely apply to study the cluster using NASA’s new James Webb Space Telescope, the successor to Hubble and expected to be available in 2020 or early 2021.

READ ALSO: Student protesters blockade UVic administrative building, fight for fossil fuel divestment

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Where’s the sea ice? 3 reasons the Arctic freeze is unseasonably late and why it matters – The Conversation US

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With the setting of the sun and the onset of polar darkness, the Arctic Ocean would normally be crusted with sea ice along the Siberian coast by now. But this year, the water is still open.

I’ve watched the region’s transformations since the 1980s as an Arctic climate scientist and, since 2008, as director of the National Snow and Ice Data Center. I can tell you, this is not normal. There’s so much more heat in the ocean now than there used to be that the pattern of autumn ice growth has been completely disrupted.

To understand what’s happening to the sea ice this year and why it’s a problem, let’s look back at the summer and into the Arctic Ocean itself.

Siberia’s 100-degree summer

The summer melt season in the Arctic started early. A Siberian heat wave in June pushed air temperatures over 100 degrees Fahrenheit at Verkhoyansk, Russia, for the first time on record, and unusual heat extended over much of the Arctic for weeks.

The Arctic as a whole this past summer was at its warmest since at least 1979, when satellite measurements started providing data allowing for full coverage of the Arctic.

With that heat, large areas of sea ice melted out early, and that melting launched a feedback process: The loss of reflective sea ice exposed dark open ocean, which readily absorbs the sun’s heat, promoting even more ice melt.

The Northern Sea Route, along the Russian coast, was essentially free of ice by the middle of July. That may be a dream for shipping interests, but it’s bad news for the rest of the planet.

Warmth sneaks in underwater

The warm summer is only part of the explanation for this year’s unusual sea ice levels.

Streams of warmer water from the Atlantic Ocean flow into the Arctic at the Barents Sea. This warmer, saltier Atlantic water is usually fairly deep under the more buoyant Arctic water at the surface. Lately, however, the Atlantic water has been creeping up. That heat in the Atlantic water is helping to keep ice from forming and melting existing sea ice from below.

It’s a process called “Atlantification”. The ice is now getting hit both from the top by a warming atmosphere and at the bottom by a warming ocean. It’s a real double whammy.

While we’re still trying to catch up with all of the processes leading to Atlantification, it’s here and it’s likely to get stronger.

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Climate change’s assault on sea ice

In the background of all of this is global climate change.

The Arctic sea ice extent and thickness have been dropping for decades as global temperatures rise. This year, when the ice reached its minimum extent in September, it was the second lowest on record, just behind that of 2012.

As the Arctic loses ice and the ocean absorbs more solar radiation, global warming is amplified. That can affect ocean circulation, weather patterns and Arctic ecosystems spanning the food chain, from phytoplankton all the way to top predators.

On the Atlantic side of the Arctic, open water this year extended to within 5 degrees of the North Pole. The new Russian Icebreaker Arktika, on its maiden voyage, found easy sailing all the way to the North Pole. A goal of its voyage was to test how the nuclear-powered ship handled thick ice, but instead of the hoped-for 3-meter-thick ice, most of the ice was in a loose pack. It was little more than 1 meter thick, offering little resistance.

For sea ice to build up again this year, the upper layer of the Arctic Ocean needs to lose the excess heat it picked up during summer.

The pattern of regional anomalies in ice extent is different each year, reflecting influences like regional patterns of temperature and winds. But today, it’s superimposed on the overall thinning of the ice as global temperatures rise. Had the same atmospheric patterns driving this year’s big ice loss off Siberia happened 30 years ago, the impact would have been much less, as the ice was more resilient then and could have taken a punch. Now it can’t.

Is sea ice headed for a tipping point?

The decay of the Arctic sea ice cover shows no sign of stopping. There probably won’t be a clear tipping point for the sea ice, though.

Research so far suggests we’ll stay on the current path, with the amount of ice declining and weather systems more easily disrupting the ice because it’s thinner and weaker than it used to be.

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The bigger picture

This year’s events in the Arctic are just part of the climate change story of 2020.

Global average temperatures have been at or near record highs since January. The West has been both hot and dry – the perfect recipe for massive wildfires – and warm water in the Gulf of Mexico has helped fuel more tropical storms in the Atlantic than there are letters in the alphabet. If you’ve been ignoring climate change and hoping that it will just go away, now would be an appropriate time to pay attention.

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New Methane Discharge Discovered in Russia's Arctic – Guardian – The Moscow Times

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A new source of methane discharge has been discovered in the Arctic Ocean near eastern Siberia, raising concerns of a “new tipping point” that could speed up the pace of global warming, The Guardian reported Tuesday. 

Scientists found the potent greenhouse gas bubbling from a depth of 350 meters in the Laptev Sea, with surface-level concentrations that vent into the atmosphere between four and eight times the normal amount. One of the six monitoring points showed methane concentrations 400 times higher than expected under the normal air-sea equilibrium.

“The discovery of actively releasing shelf slope hydrates is very important and unknown until now. This is a new page,” said Igor Semiletov, chief scientist onboard the Akademik M. Keldysh research vessel that’s part of a multi-year Russian-Swedish International Siberian Shelf Study expedition.

The discovery is prompting concerns that a new feedback loop that accelerates climate change may have already been triggered. A recent study co-authored by a member of the expedition found that the loop could be activated if the Arctic warms by just a few degrees.

At this moment, there is unlikely to be any major impact on global warming, but the point is that this process has now been triggered,” Swedish scientist and study co-author Örjan Gustafsson told The Guardian from the vessel.

This East Siberian slope methane hydrate system has been perturbed and the process will be ongoing.” 

The Guardian reported that warm Atlantic currents driven by human-induced climate disruption are the likely cause of the massive methane discharge.  

The Arctic is warming twice as fast as any other place on Earth and The Guardian reported that it is yet to begin freezing for the winter, already surpassing records for the latest date for sea ice formation after melting unusually early this spring. 

This is potentially the third source of methane emissions from the shallower parts of the Laptev Sea and the East Siberian Sea. Semiletov’s expedition released first photos of a massive fountain of methane gas bubbling from the floor of the East Siberian Sea last fall.

The scientists stressed that their findings are considered preliminary until they analyze the data collected on the ground and have their studies peer-reviewed.

The discovery of actively releasing shelf slope hydrates is very important and unknown until now,” Semiletov said. “Potentially they can have serious climate consequences, but we need more study before we can confirm that.

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Researchers Worry Methane Discovery in Arctic Ocean Could Signal Dangerous New Climate Feedback Loop – Common Dreams

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An international team of researchers aboard a Russian research ship has discovered evidence that frozen methane deposits in the Arctic Ocean have been dispersing over a large area of Siberia, potentially fueling a dangerous new climate feedback loop. 

The Guardian reports the International Siberian Shelf Study (ISSS-2020) found that slope sediments spreading over much of the continental shelf are rich in frozen methane hydrates that have been detected to a depth of 1,150 feet in the Laptev Sea.

Although the scientists said that most of the methane hydrate bubbles are dissolving in the water, methane levels at the sea surface are four to eight times higher than normal and the gas is venting into the atmosphere. What makes methane especially dangerous is that its heating effect is 80 times stronger than CO2 over 20 years. The new discovery has raised serious concerns that a new climate feedback loop may be starting.

According to ISSS-2020:

One of the greatest uncertainties surrounding climate warming [concerns] the emission of naturally accurring greenhouse gases, such as methane, carbon dioxide, and nitrous oxide (N2O) from Arctic thawing permafrost, and collapsing methane hydrates—crystals made of methane gas molecules “caged” between solid water molecules—in the seabed north of Siberia will increase in the future.  

“At this moment, there is unlikely to be any major impact on global warming, but the point is that this process has now been triggered,” Stockholm University researcher Örjan Gustafsson told The Guardian. “This East Siberian slope methane hydrate system has been perturbed and the process will be ongoing.” 

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Gustafsson, a member of the research team, warned last month that “climate warming is awakening the ‘sleeping giants’ of the carbon cycle, namely permafrost and methane hydrates.”

“How much this will lead to added emissions of the strong greenhouse gas methane is poorly understood,” he said. “This is one of the grand challenges in current climate change research and a central goal of the expedition to address.” 

The chief scientist aboard the vessel, Igor Semiletov of the Russian Academy of Sciences, called the hydrate discharges “significantly larger” than anything previously seen. 

“The discovery of actively releasing shelf slope hydrates is very important and unknown until now,” Semiletov told The Guardian. “This is a new page. Potentially they can have serious climate consequences, but we need more study before we can confirm that.” 

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