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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.

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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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New England College of Optometry Issues Safety Advisory for Solar Eclipse – New England College of Optometry

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NECO Issues Safety Advisory for Solar Eclipse – New England College of Optometry


Watching the celestial event safely is possible with the right equipment and some preparation.

With the upcoming total solar eclipse on April 8, 2024, the New England College of Optometry (NECO) urges the general public to observe this celestial phenomenon safely. Solar eclipses are rare events that spark widespread interest and excitement. To ensure everyone can enjoy the eclipse without risking their vision, NECO is sharing crucial guidelines for proper viewing.  

“Solar eclipses present a wonderful opportunity for communities to engage with astronomy, but it’s vital that safety is a  priority,” says George Asimellis, PhD, Msc, MBA, Professor of Vision Science at NECO. “Viewing a solar eclipse without appropriate protection can result in solar retinopathy, which can cause lasting damage to the eyes. You must take proper precautions to view the eclipse.” PLEASE NOTE: NECO recommends that individuals who have recently undergone eye surgery or who have chronic eye conditions should refrain from viewing the eclipse. 

Student helps patient pick glasses frame

To prevent eye injuries and ensure a memorable experience, NECO advises the following: 

  • Always use solar viewing glasses. “When gearing up to watch the magical solar eclipse, it’s important to use specialized solar filters known as ‘eclipse glasses,’” says Alina Reznik, OD ’16, NECO Alumni Liaison. “These viewers adhere to the international safety standard ISO 12312-2 for safe viewing.” The ISO certification should be visible somewhere on the product. Ordinary sunglasses, even those with UV protection, are NOT safe for looking directly at the sun. They transmit thousands of times too much sunlight to be used for solar viewing.
  • If you wish to capture the event, do not look at the sun through camera viewfinders or phone cameras, as this can also lead to serious eye damage and can even destroy a phone. 
  • The safest way to view the eclipse is to create a camera obscura by finding a piece of cardboard and piercing a small hole in the center. With your back to the sun, hold the cardboard at shoulder height. In your other hand, hold a sheet of paper and align it with the cardboard until you see a tiny image of the sun projected onto the surface of the paper. You can even put cardboard around the “screen” to block out ambient light and see the eclipse image more clearly.

NECO will host an eclipse viewing party on Monday, April 8, from 2:00-4:00pm at their main campus located at 424 Beacon Street in Boston’s Back Bay. Media are welcome to attend and receive a free pair of eclipse viewing glasses. Faculty will be present to talk about the science behind safely viewing an eclipse.

The map below (courtesy of NASA) shows the eclipse’s path of totality.

For those who reside outside the path of totality: The Boston area is outside the eclipse’s path of totality. However, we will be able to view a partial eclipse starting at about 2:10pm. Our area will experience moderate darkness and a drop in temperature during the partial eclipse, which will last two hours. Eclipse glasses must still be used to protect  your eyes from the harmful rays of the sun, even during a partial eclipse!

Our vision experts are available for comment and additional information on eye care during this astronomical event. Please contact our Marketing Department by calling (617) 587-5609, or email [email protected].

For more information from national experts on the April 8 solar eclipse, visit NASA or the American Optometric Association.

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Global wildlife study during COVID-19 shows rural animals are more sensitive to human activity

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Plant-eating animals more active, carnivores more cautious around humans 

One of the largest studies on wildlife activity—involving more than 220 researchers, 163 mammal species and 5,000 camera traps worldwide—reveals that wild animals react differently to humans depending on where the animals live and what they eat.

Bigger herbivores—plant-eating animals like deer or moose—tend to become more active when humans are around, while meat-eaters like wolves or wolverines tend to be less active, preferring to avoid risky encounters.

Urban animals like deer or raccoons may become more active around people, as they get used to human presence and find food like garbage or plants, which they can access at night. But animals living farther from cities and other developed areas are more wary of encountering people.

Wildlife during the pandemic ‘anthropause’

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Dr. Cole Burton

The new study, a collaboration across researchers from 161 institutions, used data from before and during the COVID-19 lockdowns to examine wildlife behaviour amid changing human activity levels.

“COVID-19 mobility restrictions gave researchers a truly unique opportunity to study how animals responded when the number of people sharing their landscape changed drastically over a relatively short period,” said lead author Dr. Cole Burton, an associate professor of forest resources management at UBC and Canada Research Chair in Terrestrial Mammal Conservation.

“And contrary to the popular narratives that emerged around that time, we did not see an overall pattern of ‘wildlife running free’ while humans sheltered in place. Rather, we saw great variation in activity patterns of people and wildlife, with the most striking trends being that animal responses depended on landscape conditions and their position in the food chain.”

In Canada, researchers monitoring areas such as Banff and Pacific Rim national parks, Cathedral, Golden Ears and South Chilcotin Mountains provincial parks, and the Sea-to-Sky corridor in B.C. found that carnivores like wolverines, wolves and cougars were generally less active when human activity was higher.

In several of these parks, and in cities such as Edmonton, large herbivores often increased their activity but became more nocturnal with the presence of more humans. Large carnivores were notably absent from the most human-dominated landscapes.

A coyote warily investigating a camera trap in Malcolm Knapp Research
Forest, British Columbia, Canada. Photo credit: Dr. Cole Burton, UBC WildCo

Preventing conflict through smart conservation measures

These findings highlight the importance of measures to minimize any detrimental effects of human disturbance on wildlife, including reducing overlaps that might lead to conflict.

Dr. Kaitlyn Gaynor

“In remote areas with limited human infrastructure, the effects of our actual presence on wildlife may be particularly strong. To give wild animals the space they need, we may consider setting aside protected areas or movement corridors free of human activity, or consider seasonal restrictions, like temporary closures of campsites or hiking trails during migratory or breeding seasons,” said study co-author and UBC biologist Dr. Kaitlyn Gaynor.

She added that strategies must also fit specific species and locations. In more remote areas, keeping human activity low will be necessary to protect sensitive species. In areas where people and animals overlap more, such as cities, nighttime is an important refuge for wildlife, and keeping it that way can help species survive. Efforts may focus on reducing human-wildlife conflict after dark, such as more secure storage of trash bins to reduce the number of animals getting into human food sources, or use of road mitigation measures to reduce vehicle collisions.

The findings are particularly useful amid the surge in global travel and outdoor recreation post-pandemic, Dr. Burton added.

“Understanding how wildlife respond to human activity in various contexts helps us develop effective conservation plans that have local and global impact. For that reason, we are working to improve wildlife monitoring systems using tools like the camera traps that made it possible to observe animal behaviours during the pandemic.”

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Three Canadian Student CubeSats Set for ISS Launch

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Longueuil, Quebec, – On , three CubeSats designed and built by Canadian students will launch to the International Space Station (ISS).This is the fourth and final launch of miniature satellites under the Canadian CubeSat Project. The teams finalized preparations of their CubeSats in at the Canadian Space Agency (CSA). The teams are:

  • QMSat – Université de Sherbrooke
  • Killick-1 – Memorial University
  • VIOLET – University of New Brunswick

Live coverage of the launch will air on NASA Live.

/Public Release. This material from the originating organization/author(s) might be of the point-in-time nature, and edited for clarity, style and length. Mirage.News does not take institutional positions or sides, and all views, positions, and conclusions expressed herein are solely those of the author(s).View in full here.

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