- QMSat – Université de Sherbrooke
- Killick-1 – Memorial University
- VIOLET – University of New Brunswick
Live coverage of the launch will air on NASA Live.
Danish and Swedish researchers have dated the enormous Hiawatha impact crater, a 31 kilometer-wide meteorite crater buried under the Hiawatha Glacier in northwestern Greenland. The dating ends speculation that the meteorite has anything to do with the Younger Dryas climate shift or the extinction of the megafauna about 10,000 years ago.
Ever since 2015, when researchers at the University of Copenhagen’s GLOBE Institute discovered the Hiawatha crater, uncertainty about the crater’s age has been the subject of considerable speculation. Could the asteroid have slammed into Earth as recently as 13,000 years ago, when humans had long populated the planet? Could its impact have catalyzed a nearly 1,000-year period of global cooling known as the Younger Dryas? Could this climatic shift explain the extinction of the iconic megafauna, including mammoths?
Covered by more than 1,000 meters of ice, it is not possible to access the crater and directly determine its age. Based on ice thickness and rates of ice erosion, experts suggested that the crater was at least 12,000 to 100,000 years old.
According to a news release by the University of Copenhagen, an analyses performed on grains of sand and rocks washed by meltwater from the crater site to the borders of the glacier, the Hiawatha impact crater is far older. In fact, a new study published in the journal Science Advances today reports its age to be 58 million years old.
“Dating the crater has been a particularly tough nut to crack, so it’s very satisfying that two laboratories in Denmark and Sweden, using different dating methods arrived at the same conclusion. As such, I’m convinced that we’ve determined the crater’s actual age, which is much older than many people once thought,” says Michael Storey, co-author of the study.
As one of those who helped discover the Hiawatha impact crater in 2015, Professor Nicolaj Krog Larsen of the GLOBE Institute at the University of Copenhagen is pleased that the crater’s exact age is now confirmed.
“It is fantastic to now know its age. We’ve been working hard to find a way to date the crater since we discovered it seven years ago. Since then, we have been on several field trips to the area to collect samples associated with the Hiawatha impact,” says Professor Larsen.
No kilometer-thick ice sheet draped Northwest Greenland when the Hiawatha asteroid rammed into Earth surface releasing several million times more energy than an atomic bomb. At the time, the Arctic was covered with a temperate rainforest and wildlife abounded—and temperatures of 20 degrees Celsius were the norm. Eight million years earlier, an even larger asteroid struck present-day Mexico, causing the extinction of Earth’s dinosaurs.
The asteroid smashed into Earth, leaving a thirty-one-kilometer-wide and one-kilometer-deep crater. The crater is big enough to contain the entire city of Washington D.C. During the impact high-pressure and high-temperature minerals, like zircon, formed in the rocks surrounding the impact site. The crystalline structure of zircon contains radioactive elements. As they decay to stable lead, the remaining levels of radioactive elements can be used to pinpoint the age of the crystal. The scientists extracted the zircon crystals from sand grains and pebbles washed by meltwater from beneath the glacier to its accessible borders.
The sand was analyzed at the Natural History Museum of Denmark by heating the grains with a laser until they released argon gas, whereas the rock samples were analyzed at the Swedish Museum of Natural History using uranium-lead dating of the mineral zircon.
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.
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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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.
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.
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.
“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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