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As the polar ice caps retreat, polar bears could struggle to survive by the end of this century, a number of university researchers wrote in a study published in the Nature Climate Change journal.The study looked at a number of sub-species of polar bears who live in the arctic and how they have adapted to reduced sea ice from 1979 to 2016. The group of researchers said that all but a few sub-species of polar bears will be able to reproduce and survive given projected conditions by 2100.Polar bears use sea ice to capture seals for food. When sea ice erodes for the summer, polar bears fast. Although polar bears are capable of fasting for months, there are limits to how long the bears can go without food.The researchers examined energy needs of polar bears, and that the amount of time polar bears would fast would lengthen to a point that makes it too challenging to survive and reproduce.While resting female polar bears can generally fast for longer periods of time, reproducing females, males and cubs all require shorter fasting periods, the research found.“Avoiding continued sea-ice decline requires aggressively mitigating greenhouse gas rise,” the researchers wrote, “and our results explicitly describe the costs to polar bears of avoiding that mitigation.”To illustrate how much sea ice is being lost, NOAA is projecting that the arctic could have ice-free summers by 2042.Scientists have long discussed the possibility that polar bears could become nearly extinct by the end of the century. Beyond reducing carbon emissions, proposals have included relocating cubs to areas of the Arctic expected to retain higher levels of sea ice have been proposed. To read the full study, click here. 1714

At 3 p.m. ET on Monday, November 26, a group of researchers will be really sweating. The NASA InSight spacecraft will try to land on Mars.After six months of flight, the lander component of the probe will detach itself from the cruise stage and head into the atmosphere. The lander component initially looks a fair bit like the re-entry capsule used in the 1960s and 1970s for the Apollo moon missions -- sort of conical, with a smooth and flat bottom. That bottom is a crucial heat shield that is designed to protect the probe as it passes through the thin Martian atmosphere.The landing is a devilishly difficult feat. The landing capsule has to batter its way through the atmosphere. It will fly through the Martian air at an initial speed of 12,300 mph, and it must hit the atmosphere at an angle of precisely 12 degrees. Any shallower, and the probe will bounce off into deep space. Any steeper, and the probe will burn itself up in a spectacular and fiery death. The probe will first touch the atmosphere six minutes and 45 seconds before landing. During this phase, it will experience acceleration 12 times that of the Earth's gravity. Were the probe a 150-pound human, during the flaming descent, it would weigh nearly a ton.About 3? minutes after the probe hits the atmosphere, a parachute will deploy, slowing down the probe even more. Fifteen seconds later, explosives will blow the heat shield off, exposing the actual InSight probe hidden inside. Ten seconds after the heat shield falls away, the probe will extend its legs, much like an airplane extends its wheels before touching down.The probe will fall for an additional two minutes attached to the parachute and protected by its conical shell. About 45 seconds before InSight lands, it will drop out of the shell and fall toward the surface. As soon as it leaves the shell, its landing rockets will ignite.The actual InSight probe looks a little bit like the Apollo moon lander, with three legs to support it and a boxy top. The rockets will slow it further and stop any remaining horizontal motion. Then, about 15 seconds before touchdown, the InSight probe will descend at a speed of 8 feet per second, before hopefully touching down gently on the Martian surface.The entire landing sequence will take about seven minutes to occur. A radio signal from Mars to Earth currently takes about eight minutes and seven seconds to get here. So the complete landing process will take place before we find out if it was successful. It will be done automatically, entirely by the probe itself. For the scientists and engineers who designed InSight, this is called "seven minutes of terror."And they are right to be worried. Mars is a graveyard of failed probes. There have been 44 attempts by various national space agencies to land on Mars. Eighteen have been successful. Twenty-three have not. Three have achieved orbit but failed at a landing.So, what does InSight hope to achieve? Well, as it happens, a lot. But it's different than the intrepid Curiosity probe, which NASA landed in 2012. InSight will not move around. Instead, it will stay put and tell us of the interior of Mars.One thing it will do is emit radio waves that we can monitor on Earth. By making careful measurements of how the frequency of the radio waves change, we will be able to measure the degree to which Mars wobbles as it rotates. That will tell us something about the core of the planet, specifically its makeup and information on the degree to which it is molten.InSight will also deploy a seismometer to listen for marsquakes (like earthquakes, but Martian-style) and for impacts of meteors on the planet. Information gleaned from the waves the seismometer detects will tell us more about the planet's interior.The third thing InSight will do is to dig below the planet's surface. Using a jackhammer, the probe will drill down 5 meters (16 feet) into the planet and, basically, it will take the planet's temperature.There are many reasons this is interesting. Taking the temperature at that depth will allow planetary scientists to determine how much heat is escaping from Mars. More broadly, this measurement will allow a clear determination of the temperature of the planet much closer to the core.This information will tell us a lot about how Mars formed, which, in turn, will add to the information of how rocky planets, including our own Earth, typically develop.And if you're more of an explorer kind of person and not so interested in Martian geology, it will also tell us how warm the planet is at modest depths, which will tell us if there is any chance of liquid water on the planet. Perhaps obviously, if the Martian subsurface is warm enough, any buried water will be in liquid form and not ice. Finding liquid water would be the key discovery that would make Martian exploration relatively easy. A relatively recent possible discovery of a buried Martian lake was promising, but the data was not conclusive. Knowing that the ground is warm would be very comforting to possible future explorers.Exploring the solar system is the first step toward exploring the stars. The InSight probe will give us --well -- insight into whether this is something that humanity will achieve in the foreseeable future.And maybe Elon Musk's bet on him getting to Mars will become true. 5329

AURORA, Colo. – The Aurora City Council unanimously adopted a resolution Monday, calling for an independent investigation into Elijah McClain’s death.The resolution calls for a three-member independent investigation team that will have at least three consultants and will be led by Jonathan Smith of the Washington Lawyers Committee for Civil Rights and Urban Affairs in Washington, D.C.The team will include consultants who have expertise in independent investigations, law enforcement and public safety accountability, civil rights, use of force, police and EMT training and criminal justice.The city council’s Public Safety, Courts and Civil Service Committee had said just last week they were still working to find a medical expert who can speak to the use of ketamine on McClain and at least one other person.The team of investigators, once formed, will “commence its work immediately and shall complete its investigation as expeditiously as possible,” according to language included in the resolution.The team would then issue a written report to the city council, present its findings to the council in a public meeting, and make the report public. The report will include recommendations to the city on the McClain incident as well as future best practices the police, fire and EMT departments should implement.McClain, 23, was unarmed when he was encountered by Aurora police on Aug. 24, 2019. Police put McClain in a carotid hold, which limits blood flow to the brain, after stopping him while he was walking home. When he became unresponsive, paramedics gave him ketamine, police have said.The officers involved in McClain's death were not arrested or charged, despite continued calls for justice from McClain's family and supporters, along with calls for an independent investigation.Aurora city leaders in June said a Connecticut attorney was leading a third-party investigation into the McClain incident. But city councilmembers Alison Hiltz, Curtis Gardener, and Angela Lawson argued that the attorney, a former police officer who has worked closely with police departments, could not provide an independent review. The city cut ties with the attorney before moving forward with the current investigation.In June, as McClain's death garnered national interest, Gov. Jared Polis appointed Attorney General Phil Weiser to investigate the officers' actions. The Colorado U.S. Attorney's Office also confirmed it is working with the Department of Justice Civil Rights Division to investigate the matter.This story was originally published by óscar Contreras at KMGH. 2585

ATLANTA (AP) — The Atlanta-based rap artist known as Lil Marlo has died, his record label said.Quality Control Music announced the death of Rudolph “Marlo” Johnson on Sunday in a social media post, saying he'll be remembered as “a man of great talent who feared nothing.” 279

AUSTIN, Texas (AP) — Austin City Limits has joined the ranks of major music festivals that have been canceled because of the coronavirus. Festival organizers said in a statement Wednesday that scrapping the three-day October event was "the only responsible solution." "Austin City Limits Music Festival will no longer take place in 2020," organizers said in the statement. "We would have loved to put on another memorable show this year, however, with the uncertainty surrounding the current situation in Texas, this decision is the only responsible solution. The health and safety of our fans, artists, partners, staff, and the entire Austin community remain our highest priority."Organizers said they plan to celebrate their 20th anniversary at next year's festival in October.The announcement comes as Texas reported a record daily high of nearly 7,000 new coronavirus cases on Tuesday and Republican Gov. Greg Abbott urges people to stay home. The festival is one of the largest in the country. The Coachella music festival in California and Bonnaroo festival in Tennessee will also not take place this year. 1120

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