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A woman who injured three people during a shooting at YouTube headquarters in Northern California has been identified as Nasim Najafi Aghdam.Aghdam, 39, was a resident of San Diego, the San Bruno Police Department said in a statement. After shooting three people at the campus in San Bruno on Tuesday, she killed herself with a handgun, authorities said. A fourth person injured an ankle while escaping the gunfire on campus.Aghdam's brother, who didn't want to be identified, told CNN affiliate KGTV that he didn't know she had a gun. 543

According to the Federal Bureau of Investigation, the number of background checks for gun sales on Black Friday reportedly slipped nearly 8% this year. However, it was the fourth-highest single-day total on record in 2020.According to USA Today, the National Instant Criminal Background Check System (NICS) recorded 186,645 checks on what's typically the biggest shopping holiday of the year, but in 2019, the FBI conducted 202,465.The agency has processed more than 32 million requests through October, which is 4 million more than the previous record set last year, which was 28.3 million.This year's Black Friday was unprecedented due to the coronavirus pandemic continues to ravage the country. According to data from Johns Hopkins University, 205,000 new cases were reported the day after Thanksgiving. 815

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

ALPINE, Calif. (KGTV) - A charter bus collided with a tree near an East County school Friday, injuring students with shattered glass.The bus collided with a tree next to Joan MacQueen Middle School in Alpine just before 5 p.m. There were at least 43 children on the bus, according to California Highway Patrol officer Mary Bailey. Some of the students were injured by shattered glass.It's not clear how the bus crashed.10News is monitoring this story: 469

After relocating most of the Republican National Convention to Jacksonville, Florida, President Donald Trump announced he has canceled the Jacksonville portion of the GOP convention for next month due to the spread of the coronavirus in Florida."I looked at my team and I said the timing for this event is not right, just not right with what's happened recently, the flare up in Florida,, to have a big convention," Trump said Thursday. "It's not the right time. It's really something that for me I have to protect the American people. That's what I've always done."A few convention activities will remain in North Carolina, Trump confirmed.Trump and Republicans opted to pick up and move most convention activities from Charlotte to Jacksonville after North Carolina’s governor would not commit to easing social distancing mandates for the convention.Trump said he still plans on delivering an acceptance speech during the convention week.While the Democratic Party hasn't officially canceled its Milwaukee convention for next month, it is encouraging delegates to stay home. The party plans on "anchoring" the convention there, hosting speeches and events with a limited number of surrogates. 1203