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Researchers announce 62 new moons of Saturn

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The paths of four of the new moons as they orbit Saturn (black circle at center) during the period 2019-2021. The colored dots mark the observed position for each moon; the dashed curve shows the orbit that connects them. Credit: University of British Columbia

The work of an international team of astronomers has resulted in the announcement of 62 new moons of Saturn, catapulting it back into first place of the “moon race” around the giant planets of our solar system.

The team is led by Edward Ashton (currently a postdoctoral fellow at Taiwan’s Academia Sinica Institute of Astronomy and Astrophysics) and includes professor Brett Gladman (Department of Physics & Astronomy at the University of British Columbia), Mike Alexandersen (Harvard Smithsonian Center for Astrophysics), Jean-Marc Petit (Observatoire de Besancon), and Matthew Beaudoin (University of British Columbia).

Over the past two decades, Saturn’s surroundings have been repeatedly examined for moons with increasing sensitivity. In this latest study, Dr. Ashton’s team used a technique known as “shift and stack” in order to find fainter (and thus smaller) saturnian moons. This method has been used for searches around Neptune and Uranus, but never for Saturn.

Shifting a set of sequential images at the rate that the moon is moving across the sky results in enhancement of the moon’s signal when all the data is combined, allowing moons that were too faint to be seen in individual images to become visible in the “stacked” image. The team used data taken using the Canada-France-Hawaii Telescope (CFHT) on top of Mauna Kea, Hawaii between 2019 and 2021. By shifting and stacking many sequential images taken during 3 hour spans, they were able to detect moons of Saturn down to about 2.5 kilometers in diameter.

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The original discovery search was done in 2019 when Ashton and Beaudoin were students at the University of British Columbia, uncovering the moons in a meticulous search of the deep CFHT imaging acquired that year. But just finding an object close to Saturn on the sky is insufficient to say for certain that it is a moon; it could in principle be an asteroid that just happened to be passing close to the planet (although this is unlikely).

To be absolutely sure, the object must be tracked for several years before one can establish that it is certainly orbiting the planet. After painstakingly matching objects detected on different nights over two years, the team has managed to track 63 objects, thus confirming them as new moons. One of the new moons, designated S/2019 S 1, was announced back in 2021, with the rest being announced over the last couple of weeks. Some of the team’s linked orbits were identified with past observations from many years ago that briefly glimpsed some of these moons (but were not tracked long enough to establish their orbit around Saturn).

“Tracking these moons makes me recall playing the kid’s game Dot-to-Dot, because we have to connect the various appearances of these moons in our data with a viable orbit,” explains Edward Ashton, “but with about 100 different games on the same page and you don’t know which dot belongs to which puzzle.”

All of the new moons are in the class of irregular moons, which are thought to be initially captured by their host planet long ago. Irregular moons are characterized by their large, elliptical, and inclined orbits compared to regular moons. The number of known saturnian irregular moons has more than doubled to 121, with 58 previously known before the search began.

Including the 24 regular moons, there is now a total of 145 recognized (by the International Astronomical Union) moons orbiting Saturn. The new discoveries have resulted in multiple milestones for the ringed planet. Saturn has not only regained its crown for having the most known moons (overtaking Jupiter with 95 recognized moons), it is also the first planet to have over 100 discovered moons in total.

The irregular moons tend to clump together into orbital groups based on the tilt of their orbits. In the saturnian system there are 3 such groups whose names are drawn from different mythologies: there is the Inuit group, the Gallic group, and the much more populated Norse group. For example, three new discoveries fall in the Inuit group: S/2019 S 1, S/2020 S 1 and S/2005 S 4 have very small orbits tilted similarly to that of the previously known larger irregulars Kiviuq and Ijiraq. All of the new moons fall into one of the three known groups, with the Norse group again being the most populated among the new moons. The groups are thought to be the result of collisions, where the current moons in a group are remnants of one or more collisions on the originally-captured moons.

A better understanding of the orbital distribution thus provides insight into the collisional history of the irregular moon system of Saturn. Based on their past studies of these moons, this team has suggested that the large number of small moons on retrograde orbits is the result of a relatively recent (in astronomical terms, being in the last 100 million years) disruption of a moderately sized irregular moon that is now broken into the many fragments that are being catalogued in the Norse group.

As professor Gladman explains, “as one pushes to the limit of modern telescopes, we are finding increasing evidence that a moderate-sized moon orbiting backwards around Saturn was blown apart something like 100 million years ago.”

Citation:
Researchers announce 62 new moons of Saturn (2023, May 16)
retrieved 16 May 2023
from https://phys.org/news/2023-05-moons-saturn.html

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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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