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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

Actor Will Smith, who became a household name after starring in “The Fresh Prince of Bel-Air,” shared photos from a cast reunion celebrating 30 years since the show launched.The actor posted, “Today is exactly 30 YEARS since The @FreshPrince of Bel-Air debuted! So we’re doin’ something for y’all… a for real Banks Family Reunion is comin’ soon to @HBOmax! RIP James. #FreshPrince30th” with a photo of the cast reunited. 428

After weeks of tensions, China and the United States have reached an initial agreement on trade.Both parties said in a joint statement on Saturday that China has agreed to "significantly increase" purchases of US goods and services, in order to reduce the trade imbalance between the two countries. This was a top demand of the Trump administration during two days of trade talks in Washington with Chinese officials."To meet the growing consumption needs of the Chinese people and the need for high-quality economic development, China will significantly increase purchases of United States goods and services," the statement said. "This will help support growth and employment in the United States."The pledge for more cooperation comes as the US and China, the world's two largest economies, have threatened tens of billions of dollars in tariffs that could lead to a trade war.Both sides also agreed to "meaningful increases" in US agriculture and energy exports, the statement said. The US intends to send a team to China to hammer out the details.The announcement did not put a dollar amount on the commitment from China.US officials on Thursday told CNN that Beijing had proposed boosting Chinese purchases of American goods by around 0 billion. But at a regular news briefing in Beijing on Friday, Chinese Foreign Ministry spokesman Lu Kang denied such an offer had been made. 1394

After losing her mother to COVID-19, a comedian has launched a mask-wearing crusade.Through a pixilated image on her iPad, Laurie Kilmartin strained her eyes desperately hoping to see her mother’s chest rise on the other end of their Facetime call, but after five minutes of silence, Laurie knew the coronavirus had won.Joanne Kilmartin died alone inside a California nursing home.After an hour of crying into her screen, Laurie and her sister told doctors it would be okay to end the call. They had spent the last 69 hours on FaceTime with their mom, knowing the end of her life was near.“Facetime makes this noise when it closes out and it closes out immediately, it doesn’t go to a corner and fade away. So, my mom just disappeared. There was this noise and she was pulled back into the universe,” Laurie said via a Zoom call from her home in California.Just weeks earlier, Joanne, 82, was enjoying her evening vodka martini at Laurie’s home where she’d been living. The 82-year-old had some underlying health issues but for the most part was doing okay, until one day when she started suffering from shortness of breath.Knowing what she knows now, Laurie says she likely would’ve never let her mom be checked into a short-term care facility after being discharged from a local emergency room.“It didn’t occur to me at all that this was still running through nursing homes like that,” she explained.When Joanne was checked into York Healthcare & Wellness Centre in Highland Park, California, not a single person had COVID-19. But just days later, dozens of patients had suddenly contracted the virus. After testing positive, Joanne’s condition quickly went downhill.“I couldn’t rescue her. Had I known what would happen, I would’ve gotten her a hotel room and hired a nurse,” Laurie lamented.By the time it became clear that Joanne wasn’t going to survive the virus, doctors set up an iPad in her room. Laurie and other family members would spend hours just watching their mom breath, offering words of comfort at any hint of movement. All of it done virtually in an attempt to keep the virus from spreading.COVID-19 has robbed families of the opportunity to grieve together in person.“My mom got the worst send off and at the end we were only voices that we hoped she could hear. It’s a terrible way to say goodbye to somebody, it doesn’t feel real,” Laurie said about her mom’s death.But Laurie has tried to find some purpose in her pain. As a professional comedian with a large online social media following, she decided to chronicle her mom’s final days of Twitter. It was an effort, she said, to educate the public about the true scope of the kind of suffering the virus causes. Laurie has even used her platform to criticize people who push back against mask-wearing policies.“To someone who doesn’t want to wear a mask, you’re incredibly selfish, you’re harming yourself. Even if you think, ‘Oh it’s just old people,’ do you want to lose an old person like this? Is this how you want your grandma or grandpa to go out? Is that fair?” she questioned.Having watched her mother take her final few breaths via a FaceTime call, Laurie is left to wonder why so many states are reopening as quickly as they have, even as COVID-19 cases continue to spike.“There’s over 100,000 stories like mine, and 100,000 families like mine that are shocked and numb, you could be me pretty soon.” 3397

After running a year-long competition that drew interest from hundreds of cities and a number of states, Amazon has reportedly chosen New York City and Northern Virginia to split duty as its second headquarters.The Wall Street Journal reported late Monday that Amazon (AMZN) has picked New York's Long Island City and Arlington County's Crystal City neighborhoods, citing people familiar with the matter.Amazon declined to comment to CNN.The development projects, which could be announced as soon as Tuesday, promise to bring the cities a giant infusion of jobs and tax revenue, but are almost certain to draw fire from critics concerned about their impact on infrastructure and property values. 703