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According to a recent paper, the Earth is caught directly in the crosshairs of a cosmic hurricane.A swarm of nearly 100 stars, accompanied by an even greater amount of dark matter, is aimed directly at our stellar neighborhood and there's nothing we can do to stop it; in fact, the vanguard is already upon us. This sounds like a perfect summer blockbuster movie, starring The Rock and Chris Pratt, or maybe Scarlett Johansson and Charlize Theron.Except this is for real. But is it a danger? Well, actually, no. Not at all. But it's potentially incredibly fascinating, with lots of interesting scientific interconnections. So, what is really going on?The story starts last April, when the Gaia satellite announced the locations and trajectories of 2 billion stars in the vicinity of the Milky Way surrounding our sun. They released the data to the public.Scientists were then able to look at the data set to see if they could spot anything peculiar. In galaxies like the Milky Way, the most common behavior is that the stars orbit the center of the galaxy in a manner broadly similar to the planets orbiting our sun. However, there are some stars that exhibit unusual motion. About a year ago, astronomers identified some "stellar streams" passing through our celestial neighborhood.One of them, called S1 (for stream 1), consists of nearly 100 stars of similar age and composition, orbiting the Milky Way in a direction exactly opposite that of normal stars. It's kind of like a handful of cars driving the wrong way down the highway, except with a much greater distance between them and with no likelihood of a collision. These stars are spread out over a few thousand light years and they will pass through the solar system's neighborhood over the course of a few million years.Astronomers identified S1 as being part of the remnants of a dwarf galaxy that collided with the Milky Way and was consumed in an epic episode of cosmic cannibalism. Dwarf galaxies are very small, typically about 1% the mass of the Milky Way. They can orbit larger galaxies and collide with the bigger galaxy, adding their mass to the parent. This is what appears to have happened in the case of S1, although the process has taken probably a billion years.Dwarf galaxies often have a disproportionately large fraction of dark matter. Dark matter is a hypothetical and still-undiscovered form of matter that interacts only gravitationally. Scientists have proposed its existence to explain many astronomical mysteries, for example the observation that most galaxies rotate faster than can be explained by the known laws of physics and the stars and gas of which they are composed.While dark matter has not yet been observed, hypothesizing its existence is the simplest and most economical explanation for myriad astronomical mysteries. Averaged over the entire universe, dark matter is thought to be five times more prevalent than the ordinary mass of stars and gas and planets.In dwarf galaxies, the fraction of dark matter is often higher. In Fornax, a well-studied dwarf galaxy orbiting the Milky Way, researchers estimate that the dark matter is between 10 and 100 times greater than the mass found in its stars.If that number holds for S1, the dark matter of the S1 stream is passing through the Earth at a much higher velocity than the more ordinary dark matter that orbits the Milky Way -- about twice as fast. It is thought that S1 dark matter is flying through the solar system at a speed of about 550 km/s, or about 1.2 million mph. While these numbers are impressive, they are misleading. Dark matter, if it exists, is extremely diffuse and it will have no discernible effect on the solar system.Because dark matter hasn't been observed yet, these velocity numbers are speculative, although they are strongly supported by a very large body of evidence. However, the prospect of high velocity dark matter flying through the Earth has suggested an opportunity to detect it.In a paper in the prestigious journal Physical Review D, researcher Ciaran O'Hare and his collaborators calculated the possibilities of discovering dark matter using both existing and proposed dark matter detectors. They considered two varieties of dark matter particles: a very heavy kind called a WIMP (weakly interacting massive particle) and a very light kind called an axion. Because the ultimate nature of dark matter is not known, it is important to be open to all possibilities.They found that the detectors they evaluated could find WIMPs for certain ranges of the particle mass. However, when they looked at the axion possibility, it appeared the prospects were even better. Because of its light mass and the manner in which an axion would interact with the detector, the apparatus simply has a better chance of seeing the axion. (If axions exist, of course.)Experiments with names like ADMX, MADMAX and ABRACADABRA are able or will be able to search for the signatures of dark matter proposed in the recent paper. They consist of technologies that are designed to interact with axions in a strong magnetic field and convert them to ordinary microwaves or radio waves that can be easily detected.It's important to remember that the S1 stream poses no credible threat to the Earth and humanity. There is no need for an action hero to save us. However, the synergy of science is staggering. A careful catalog of nearby stars has opened the prospect of a better possibility of finding and identifying dark matter, which is one of the great unanswered mysteries of modern physics. It's an amazing time we live in, in which we can study such things.\ 5625

According to a new survey released by the United States Department of Education, 94 percent of teachers said they spent their own money on classroom supplies during the 2014-2015 school year, and the average amount spent was 9.Early childhood education teacher Natalie Soto-Mehle says one of the things she loves most about the three and four-year-olds who make up her class at Trevista Elementary School in Denver is their “energy and joy for life.”So she chooses to do all she can to make their day as engaging as possible.“We might want some sparkly pencils to make it a little bit more interesting,” she said, adding that she’d be buying these types of things with her own money.She acknowledges that a lot of what she buys wouldn’t be considered “essential” by many people, but they’re ways that she can make the experience better for her students.“We have a great library, and I do use it, but I want the books for future use so I’ll buy the books that I want,” she said.Soto-Mehle says she probably buys over ,000 worth of extra supplies for her students each year. She can even remember a few years that hit the ,000 mark.But she just chalks it up to being a teacher.“It’s part of what you do,” she said.Does it surprise Soto-Mehle that 94 percent of teachers pay for supplies out of their pocket? Not at all, adding that she “knows a lot of teachers” who do the same.Some of the expenses she incurs are for art supplies like markers, crayons, and paints; storage contains like bins and baskets; picture books that she wants to keep for her students from one year to the next; even houseplants for the room.In her classroom, she’s fortunate in that many of the students’ families contribute things like art supplies and tissues to the school’s pot at the beginning of the year.But when you’re supply “runs out mid-year” as Soto-Mehle says can happen, she doesn’t want to go back to the families.“You don’t want to ask families to pitch in,” she said, adding that “it’s important to me, so I’m not complaining about it.” 2052

After Hurricane Laura hammered parts of the Gulf Coast, communities are coming together with people helping people.“The battle cry is out there,” said Curtis Drafton, who is gearing up for a private rescue mission. “The bell is tolling. Let’s go get it!”This United States Army veteran, who spent his life helping others, is now spending his own money to do the same as a civilian.“Last year we spent around ,533,” he said.Drafton is leading the Veteran Emergency Response Unit, a nonprofit providing relief during natural disasters.“It’s not really about the money,” he said. “It’s like, Americans are suffering, Americans are dying and at the end of the day, somebody has got to pick up the slack.”About an hour outside of Baton Rouge in Gator Country, neighbors gathered to help remove a fallen tree off Paige Fontenote’s brand new outdoor carport that was crushed during the storm.“It touches my heart; it makes me want to cry,” she said.Overcome with emotions, Fontone almost broke down from the support from people in the area where she wants to retire.“This is what it’s all about,” she said. “This is why we want to move here.”In Lafayette, Louisiana, homeowners took matters into their own hands, chopping down a fallen tree between a home and an apartment complex.“You cook a gumbo, you hope nothing doesn’t happen to your house and then you get out and help your friends,” said one local man.Helping friends in this time of need as people continue to help other people.“If 2020 hasn’t taught us anything that would be it,” the man said. “Turn the TV off, spend time with your neighbors and do it for them.” 1628

A White House official has spent about three months in the hospital recovering from severe complications following a COVID-19 diagnosis, including the amputation of his right foot and lower leg, according to multiple sources.Crede Bailey is the director of the White House security office and contracted COVID-19 in September. He was reportedly hospitalized shortly before the September 26 event at the White House officially nominating Justice Amy Coney Barrett, according to The Hill.A friend told Bloomberg Bailey’s family asked the White House not to publicize his condition, and President Donald Trump has not acknowledged Bailey’s illness.Bailey’s friends have set up a GoFundMe account to help pay for the White House official’s and his family’s “medical and healing expenses necessary as a result of Crede's COVID-19 illness and the life-altering results.”In an update posted on December 7, the fundraiser’s organizer, Dawn McCrobie posted a big update on Bailey’s condition.“Crede has recently been released from the ICU and is now at a full-time rehabilitation center where he is focused on gaining strength and learning to live a new normal. Crede beat COVID-19 but it came at a significant cost: his big toe on his left foot as well as his right foot and lower leg had to be amputated,” the update reads.McCrobie said Bailey will be fitted for a prosthetic leg in the next few months.The fundraiser has gotten more than the ,000 in donations they were originally seeking. In her updates, McCrobie says the money will be used not only for medical bills, but also to help renovate Bailey’s home to be more accessible for a wheelchair.Bailey oversaw the security office, which handles credentialing for access to the White House and works with the Secret Service on security measures. 1804

Actor Bill Murray is mourning the passing of his older brother Ed. Murray's golf apparel company, William Murray Golf, confirmed Ed's death on Tuesday in a brief Facebook post.According to the golf apparel's website, Ed Murray was the eldest Murray brother.On Monday, Ed's younger brother Joel tweeted in remembrance of his brother, who was "the nice Murray who remembered everyone's name." 398

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