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Earth Is a Whole Lot Closer to Our Galaxy's Supermassive Black Hole Than We Thought – ScienceAlert

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It seems that Earth has been misplaced.

According to a new map of the Milky Way galaxy, the Solar System’s position isn’t where we thought it was. Not only is it closer to the galactic centre – and the supermassive hole therein, Sagittarius A* – it’s orbiting at a faster clip.

It’s nothing to be concerned about; we’re not actually moving closer to Sgr A*, and we’re in no danger of being slurped up. Rather, our map of the Milky Way has been adjusted, more accurately identifying where we have been all along.

And the survey beautifully demonstrates how tricky it is to map a galaxy in three dimensions from inside it.

It’s a problem that has long devilled our understanding of space phenomena. It’s relatively easy to map the two-dimensional coordinates of stars and other cosmic objects, but the distances to those objects is a lot harder to figure out.

And distances are important – they help us determine the intrinsic brightness of objects. A good recent example of this is the red giant star Betelgeuse, which turned out to be closer to Earth than previous measurements suggested. This means that it’s neither as large nor as bright as we thought.

Another is the object CK Vulpeculae, a star that exploded 350 years ago. It’s actually much farther away, which means that the explosion was brighter and more energetic, and requires a new explanation, since previous analyses were performed under the assumption it was relatively low energy.

But we’re getting better at calculating those distances, with surveys using the best available technology and techniques working hard to refine our three-dimensional maps of the Milky Way, a field known as astrometry. And one of these is the VERA radio astronomy survey, conducted by the Japanese VERA collaboration.

VERA stands for VLBI (Very Long Baseline Interferometry) Exploration of Radio Astrometry, and it uses a number of radio telescopes across the Japanese archipelago, combining their data to effectively produce the same resolution as a telescope with a 2,300 kilometre- (1,430 mile-) diameter dish. It’s the same principle behind the Event Horizon Telescope that produced our very first direct image of a black hole’s shadow.

VERA, which started observing in 2000, is designed to help us calculate the distances to radio-emitting stars by calculating their parallax. With its incredible resolution, it observes these stars for over a year, and watches how their position changes relative to stars that are much farther away as Earth orbits the Sun.

(National Astronomical Observatory of Japan)

This change in position can then be used to calculate how far a star is from Earth, but not all parallax observations are created equal. VLBI can produce much higher resolution images; VERA has a breathtaking angular resolution of 10 millionths of an arcsecond, which is expected to produce extraordinarily high precision astrometry measurements.

And this is what astronomers have used to refine our Solar System’s position in the Milky Way. Based on the first VERA Astrometry Catalog of 99 objects released earlier this year, as well as other observations, astronomers created a position and velocity map of those objects.

From this map, they calculated the position of the galactic centre.

In 1985, the International Astronomical Union defined the distance to the galactic centre as 27,700 light-years. Last year, the GRAVITY collaboration recalculated it and found it closer, just 26,673 light-years away.

solar system gc(National Astronomical Observatory of Japan)

The VERA-based measurements bring it closer still, to a distance of just 25,800 light-years. And the Solar System’s orbital speed is faster, too – 227 kilometres (141 miles) per second, rather than the official velocity of 220 kilometres (137 miles) per second.

That change may not seem like much, but it could have an impact on how we measure and interpret activity in the galactic centre – ultimately, hopefully, leading to a more accurate picture of the complex interactions around Sgr A*.

Meanwhile, the VERA collaboration is forging ahead. Not only is it continuing to make observations of objects in the Milky Way, it’s joining up with an even larger project, the East Asian VLBI Network. Together, astronomers hope, the telescopes involved in this project could provide measurements of unprecedented accuracy.

The Vera Astrometry Catalog was published in the Publications of the Astronomical Society of Japan.

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UOttawa startup gets $4M funding boost for technology that curbs 'freezer burn' in stem cell tissue – Ottawa Business Journal

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A biotech startup co-founded in Ottawa has landed millions of dollars in new funding for its pioneering solution that helps preserve human cells used in next-generation medical research.

PanTHERA Cryosolutions says it’s secured a $4-million investment from a pair of U.S.-based firms, Washington state-based BioLife Solutions and New York’s Casdin Capital, to help get its system ready for market over the next two years. In exchange, BioLife will receive exclusive worldwide marketing and distribution rights to PanTHERA’s products for use in its cell and gene therapy applications.

Founded four years ago by University of Ottawa chemistry professor Robert Ben and University of Alberta researcher Jason Acker, PanTHERA makes small organic molecules that slow down the buildup of ice ​– known as recrystallization ​– that occurs when biological material used in the fields of cell therapy and regenerative medicine is frozen.

Scientists have been freezing cells and tissues for decades to preserve them for research into therapies for a wide range of diseases, explained Ben, who specializes in synthetic organic and medicinal chemistry. 

Protective agents such as glycerol are used to prevent the cells from drying out in the freezing and thawing process, he said. But that process “is kind of hit and miss,” Ben noted in a recent post on uOttawa’s website.

Preventing cellular damage

“We might freeze 100,000 cells, but only 25,000 will survive and be viable for research or clinical applications,” he said, likening the process to “freezer burn” that changes the structure ​– and subsequently the taste – of ice cream that’s been stored for too long. 

“That’s because up to 80 per cent of the cellular damage that happens during freezing is due to the uncontrolled growth of ice. Since current cryoprotectant solutions don’t address this problem, our returns, measured in cell recovery and function, are quite dismal.”

PanTHERA’s technology also allows cells to survive at higher temperatures than traditional methods, making it easier to store and ship them to remote locations.

“Small ice crystals are innocuous,” Ben said. “They’re like grains of sand on a Caribbean beach. They’re so small that they mould to your body and you can lay comfortably on the beach for an entire day. Now, let’s say those grains of sand were replaced by gravel or pebbles. That’s a lot less comfortable. Our cryopreservation technology prevents ice crystals from growing too large for comfort.”

For the past 10 months, Ben and his team have been working on a new class of compounds that can protect proteins and viruses. They’re now in the process of proving that the technology can preserve COVID testing materials and RNA-based vaccines.

“Our molecules are unique because, unlike conventional cryoprotectants, they prevent all that cellular damage caused by ice,” Ben said. “In the end, we recover more cells, they’re healthier and more functional. There is nothing else like it out there.”

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Global Ice Loss Is Speeding Up: the Risks of Melting Ice Sheets – Green Matters

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Melting ice sheets is one of the most cliché signifiers of global warming and the climate crisis — but clichés originate in the truth, after all, and ice sheets are still melting. In fact, new research has found that the rate of global ice loss — aka melting ice sheets — is higher than ever before.

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On Monday, Jan. 25, 2021, researchers from the University of Leeds, the University of Edinburgh, University College London, and Earthwave published their findings in European Geosciences Union’s journal The Cryosphere.

ice melt
Source: Getty Images

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According to the study, ice melt over the past three decades has steadily increased — in the 1990s, there was an average global ice melt of 0.8 trillion tonnes per year; by 2017, there was an average of 1.3 trillion tonnes per year. In total, the rate of ice loss has increased by 65 percent between 1994 and 2017.

Overall, between 1994 and 2017, planet Earth lost 28 trillion tonnes of ice. To put that in perspective, that would be equivalent to a 100-meter-thick sheet of ice the size of the U.K.

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This melting ice has been the most concerning in two polar climates: Antarctica and Greenland. 58 percent of the ice loss happened in the northern hemisphere, while the other 42 percent happened in the southern hemisphere.

“Although every region we studied lost ice, losses from the Antarctic and Greenland ice sheets have accelerated the most,” lead author Dr. Thomas Slater said in a statement for the University of Leeds. “The ice sheets are now following the worst-case climate warming scenarios set out by the Intergovernmental Panel on Climate Change. Sea-level rise on this scale will have very serious impacts on coastal communities this century.”

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This rapid ice melt poses a series of significant issues for Antarctica, Greenland, and other cold climates. For one thing, it has a strong correlation with sea level rise.

“Sea ice loss doesn’t contribute directly to sea level rise but it does have an indirect influence. One of the key roles of Arctic sea ice is to reflect solar radiation back into space which helps keep the Arctic cool,” co-author Dr. Isobel Lawrence explained in a statement. 

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“As the sea ice shrinks, more solar energy is being absorbed by the oceans and atmosphere, causing the Arctic to warm faster than anywhere else on the planet,” she continued. “Not only is this speeding up sea ice melt, it’s also exacerbating the melting of glaciers and ice sheets which causes sea levels to rise.”

As these ice sheets melt and glaciers retreat, people and animals around the world “at both local and global scales” are at risk, according to report co-author Inès Otosaka.

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On a global scale, when sea level rise gets out of hand, coastal areas experience high flood risks. Cities like Miami, New York City, and New Orleans could wind up underwater by the end of this century if we don’t take action, as reported by Business Insider.

On a local scale, “mountain glaciers are also critical as a freshwater resource for local communities,” as per Otosaka. With fewer mountain glaciers, people who depend on these for a source of water could suffer. Not to mention, animals who rely on or live on glaciers and ice sheets may suffer; according to GlacierHub, this long list of animals includes polar bears, penguins, seals, snow leopards, bison, and reindeer.

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Scientists find a cloudless 'hot Jupiter' exoplanet with a four-day year – Yahoo Movies Canada

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The Canadian Press

EU proposes more travel restrictions to stop virus variants

BRUSSELS — The European Union’s executive body proposed Monday that the bloc’s 27 nations impose more travel restrictions to counter the worrying spread of new coronavirus variants but make sure to keep goods and workers moving across EU borders. Amid concerns related to the production and delivery of COVID-19 vaccines, the European Commission urged EU nations to reinforce testing and quarantine measures for travellers as virus mutations that are more transmissible threaten to overwhelm European hospitals with new cases. More than 400,000 EU citizens have already died from the virus since the pandemic first hit Europe last year. “The start of the EU vaccination campaign kicked off the beginning of the end of the pandemic,” EU Justice commissioner Didier Reynders said. “At the same time, new, more transmissible variants of the virus have surfaced. There is currently a very high number of new infections across many member states. And there is an urgent need to reduce the risk of travel-related infections to lessen the burden on overstretched healthcare systems.” Among the new measures, which need to be approved by EU nations before taking effect, is the addition of a new “dark red” colour to the EU’s weekly map of infections. Reynders said this new colour highlights areas where the rate of new confirmed infections in the last 14 days is 500 or more per 100,000 inhabitants. He said between 10 and 20 EU countries would already see that colour on all or part of their territory if it was in effect now. “We also think it is necessary for essential travellers arriving from dark red areas to get tested before travelling and to undergo quarantine, unless these measures would have a disproportionate impact on the exercise of their essential function,” Reynders said. Since the discovery of the new virus variants, several EU countries have already reinforced their lockdown measures. Belgium has introduced a ban on all nonessential travels for its residents until March, while France could soon start a third lockdown if a stringent 12-hour daily curfew already in place can’t slow down the spread of new infections. “We are suggesting stricter measures for dark red areas, because we must recognize the high level of cases,” Reynders said. Insisting that all non-essential travel is “strongly discouraged,” the commission repeated the need to keep the single market functioning so workers and goods can continue to cross borders smoothly, “Border closures will not help, common measures will,” Reynders said. The commission also proposed that travellers from outside the EU should face mandatory coronavirus testing before they depart, tests once they arrive, mandatory quarantines for up to 14 days and hand over data for contact tracing. It suggested EU citizens and residents take a coronavirus test upon arrival and could face further restrictions if they coming in from a country where a variant has been detected. ___ Follow AP coverage of the virus outbreak at: https://apnews.com/hub/coronavirus-pandemic https://apnews.com/hub/coronavirus-vaccine https://apnews.com/UnderstandingtheOutbreak Samuel Petrequin, The Associated Press

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