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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 multiple reports, Amtrak is planning to furlough nearly 2,000 workers beginning Oct. 1.According to USA Today, the railroad company sent a letter to employees on Tuesday, detailing that 1,950 union workers and 100 management positions would be furloughed.In May, the company sent Congress a letter, stating it needed close to .5 billion in supplemental funds and disclosed plans to furloughing employees in the coming budget year.The New York Times reported that ridership has fallen by 95 percent since March, and projected revenue for 2021 declined by 50 percent. 588

A woman accused of mailing poison to President Donald Trump sent six similar letters to prison officials in Texas, according to court documents obtained by Scripps station WKBW in Buffalo, New York.Pascale Ferrier was arrested Sunday on the Peace Bridge — the bridge over Lake Erie that connects the U.S. and Canada at Buffalo, New York. Pascale, who was reportedly in possession of a gun and a knife, was charged with threatening the President of the United States.Ferrier's arrest came a day after the FBI announced it was investigating a suspicious letter addressed to Trump that contained ricin, a poison found naturally in castor seeds.According to an arrest warrant obtained Tuesday, Ferrier's referred to Trump in her letter as "The Ugly Tyrant Clown," and called for him to resign."You ruin USA and lead them to disaster. I have US cousins, then I don't want the next 4 years with you as president. Give up and remove your application for this election," she allegedly wrote.Ferrier's letter also referred to a "special gift" included in the envelope."This gift is in this letter," she allegedly wrote. " If it doesn't work, I'll find better recipe for another poison, or I might use my gun when I'll be able to come. Enjoy! FREE REBEL SPIRIT."According to an affidavit, the letters found in Texas also included a powdery substance, references to trying "another recipe" and also included the signature "FREE REBEL SPIRIT." Fingerprints taken from the letters match Ferrier's prints on file, according to court paperwork.The Royal Canadian Mounted Police are also investigating the incident. Monday, CTV News in Canada reported that they conducted an operation in St-Hubert, which is south of Montreal, Quebec.Ferrier is due in Federal Court in downtown Buffalo on Tuesday afternoon. 1799

Actress Kate Walsh, best known for her role in the TV series "Grey's Anatomy," went public on Monday with a brain tumor diagnosis in 2015."I was shocked," Walsh said of the moment doctors revealed her MRI results. "It was not what I expected."Walsh was diagnosed with a meningioma: a tumor arising from the lining that surrounds the brain and spinal cord. Within three days, she underwent surgery to have it removed at Cedars-Sinai Medical Center in Los Angeles. After removing the tumor, doctors confirmed that it was benign.In January 2015, Walsh initially wrote off symptoms as exhaustion, having just executive produced and starred in the NBC series "Bad Judge.""I could drink five cups of coffee and not wake up," she said.She found it hard to concentrate. Her balance was off, and she developed shooting headaches. Her Pilates instructor also noticed that she would dip on her right side.Exercise is "typically when people will see subtle motor changes, because they're really comparing both sides of their body," CNN Chief Medical Correspondent Dr. Sanjay Gupta said.Her cognitive issues became severe enough that her then-boyfriend urged her to see a neurologist."I would reach for words or thoughts, and I just couldn't finish them," Walsh said.By the time she made it to the doctor in June 2015, he even noticed that the right side of her face was drooping slightly. It was then that doctors found the benign tumor, which was just over 5 centimeters long, pushing on her left frontal lobe.Doctors put Walsh on a precautionary antiseizure medication before she went under the knife. With a tumor that size pressing on her brain, they told her she was lucky to have had no seizures.Despite having played Dr. Addison Montgomery on "Grey's Anatomy" and the spinoff "Private Practice," she was blindsided by the diagnosis and her sudden role as the patient. For all the medical jargon she delivered as a TV doctor, she hadn't heard of meningiomas."How meta," Walsh said of her transition from onscreen doctor to real-life patient.Meningiomas, which are more likely to occur in women, are usually benign and slow-growing. Doctors told Walsh that the tumor may have been there for a while -- but that could mean two years or 10 years, she was told.Most meningiomas arise close to the skull, but in some cases, a tumor can form as far down as the spinal cord.These tumors differ greatly from aggressive brain cancers like glioblastoma, which may originate deeper in the brain and can "double in size every couple of weeks," Gupta said. Sen. John McCain was diagnosed with glioblastoma in July.Meningiomas are the most common tumors that originate in the central nervous system, numbering about 27,000 cases per year, based on 2009-13 data from the Central Brain Tumor Registry in the United States.Some are removed surgically without further treatment, as Walsh's was. However, in some cases in which the tumor is very small and causes no symptoms, doctors may simply watch and wait, Gupta said. In less common cases in which malignant cells are found in the tumor or when the tumor is next to delicate structures like the brain stem, doctors may also opt for radiation, Gupta added.Other celebrities have gone public with their own meningioma diagnoses -- including Sheryl Crow, Elizabeth Taylor, Mary Tyler Moore and recently Maria Menounos.Immediately after her surgery, Walsh said, she noticed a difference."The fog had lifted," she said.Walsh said that her decision to go public was intended to help raise awareness, especially of a type of tumor that affects mostly women. She joined "Grey's" co-star Patrick Dempsey and other TV doctors in a campaign launched by Cigna that encourages people to get annual checkups."I was so relieved to know that it was something" that could be fixed, Walsh said of the tumor. Her advice: "Trust your instincts. Trust your body." 3905

Alaska Airlines has resumed flights in Portland and Spokane after temporarily suspending them on Monday due to hazardous air quality.In a blog post on their website, the airline company said they canceled dozens of Alaska Airlines and Horizon Air flights in Portland and Spokane.The flights were canceled on Monday at 5 p.m. PT but resumed them on Tuesday at 3 p.m. PT.Thirty-six people have now perished due to the wildfires that are ravaging California, Oregon, and Washington.The Beachie Creek fire, which is currently burning in the northern part of the state since Aug. 16, is 15% contained, according to the Oregon wildfire dashboard. 648

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