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The Geminid meteor shower peaks this week, so hope for clear skies that will let you see a beautiful show of green fireballs on Thursday and Friday. This will be the last -- and strongest -- meteor shower of the year, according to NASA.This phenomenon was first recorded in 1862 and causes a show each December.In the hours before sunrise Friday, the most meteors will be visible in the North American sky, peaking about 7:30 a.m. ET, predicts Sky & Telescope. To see when they will peak in your part of the world, check here.But the morning isn't your only chance. On Thursday and Friday, keep an eye on the sky a few hours after sunset -- just keep the moon at your back.Although the Geminid shower is known for its "shooting stars," the number of meteors visible depends on the time and how dark it is. There will be fewer of them earlier in the evening, but the shower should hit a maximum of about 100 per hour around 2 a.m., NASA said. For those in the suburbs, expect about 30 to 40 per hour. And if you're in a city like New York, San Francisco or Atlanta, you probably won't see anything.Early evening meteors may be longer, with dramatic streaks that last several seconds. Later on, the meteors will present quicker streaks or leave trails of smoke that appear to glow.The asteroid 3200 Phaethon is responsible for this meteor shower, which is unusual because comets usually create meteor showers with icy debris. Scientists have debated the very nature of what Phaethon is. The closely tracked near-Earth asteroid has been likened to comets, so it's been called a "rock comet."Phaethon was discovered in October 1983 and named after the Greek myth about the son of Helios, the sun god, because it closely approaches our sun.Phaethon orbits the sun closer than any other asteroid and takes 1.4 years to orbit it. The asteroid heats to about 1,300 degrees Fahrenheit on closest approach to the sun, which causes it to shed dusty debris.These particles cause the meteor shower when they plunge into Earth's atmosphere at 22 miles per second, vaporizing in the streaks we call "shooting stars."If you live in an urban area, you may want to drive to a place that isn't littered with city lights that will obstruct your view. If you're able to find an area unaffected by light pollution, meteors could be visible every couple of minutes from 10 p.m. until dawn.Find an open area with a wide view of the sky, and don't forget to bundle up. Make sure you have a chair or blanket so you can look straight up. And give your eyes about 20 to 30 minutes to adjust to the darkness -- without looking at your phone -- so meteors are easier to spot.While you're keeping an eye out for the meteor shower, you might see a small, foggy green patch in the sky, NASA said. That will be Comet 46P/Wirtanen, which is making its closest approach to Earth -- within 7 million miles -- for the next 20 years. And it will be visible to the naked eye. The comet is expected to come closest to Earth and peak Sunday. 3007

The flu vaccine may have an important benefit beyond protecting against influenza: It may also prevent heart attacks, especially in those at high risk, experts say."It's been a long time that people have recognized that association with flu season and development of a heart attack," said Dr. Kevin Schwartz, an infectious disease physician at Public Health Ontario.When it comes to preventing heart attacks in people with cardiovascular problems, experts have put getting the flu vaccine on par with long-term measures such as quitting smoking or taking one's medication for high blood pressure.  610

The coronavirus has had a significant impact on sports, and now football is beginning to see the virus affect the sport.NFL Network reports that the league and players’ union agreed to not hold a preseason this fall, which would have gotten underway next month. Given football’s schedule, the games provide teams with revenue as they’re generally included in season ticket packages. The decision comes with the likelihood of teams playing in front of no or a limited number of fans during the regular season. Several states have said that large gatherings will be limited into the fall.NFL Network added the league will expand training camp rosters, and there will be an opt-out for players at a “high risk” of having coronavirus complications. 752

The Centers for Disease Control and Prevention say four people have died and 11 others have been hospitalized after they ingested hand sanitizer.In the report, the CDC said the 15 adults, 13 of which were men, were being treated for methanol poisoning, which occurred in New Mexico and Arizona between May and June.The CDC said three people suffered vision problems."Alcohol-based hand sanitizer products should never be ingested," CDC officials said in the report. "In patients with compatible signs and symptoms or after having swallowed hand sanitizer, prompt evaluation for methanol poisoning is required. Health departments in all states should coordinate with poison centers to identify cases of methanol poisoning."As of July 8, four people were still hospitalized, the report stated."Among the four patients who died, three had seizures at the time of admission; initial signs and symptoms were not reported for the fourth patient," the report said.According to the report, the average age was 43, with some of the incidents happening amongst Native Americans. 1076

The Centers for Disease Control and Prevention issued new guidance that recent studies have indicated that cloth masks offer more protection against the coronavirus than previously thought.Previous guidance suggested that masks were best used for preventing the spread of the virus. The CDC now believes that masks are effective for both stopping the spread and reception of the virus. The CDC said on Tuesday that multi-layer cloth masks can both block up to 50 to 70% of fine droplets and particles and limit the forward spread of those that are not captured. Overall, cloth masks offer up to 80% blockage in human experiments. The CDC’s analysis found that cloth masks offer comparable protection as surgical masks.“Studies demonstrate that cloth mask materials can also reduce wearers’ exposure to infectious droplets through filtration, including filtration of fine droplets and particles less than 10 microns,” the CDC’s guidance said. “The relative filtration effectiveness of various masks has varied widely across studies, in large part due to variation in experimental design and particle sizes analyzed. Multiple layers of cloth with higher thread counts have demonstrated superior performance compared to single layers of cloth with lower thread counts, in some cases filtering nearly 50% of fine particles less than 1 micron.”The guidance says that mandatory mask wearing can help prevent the need to implement economic shutdowns.“Adopting universal masking policies can help avert future lockdowns, especially if combined with other non-pharmaceutical interventions such as social distancing, hand hygiene, and adequate ventilation,” the CDC said.In an interview with Andrea Mitchell of MSNBC, Dr. Anthony Fauci said that wearing masks is “two-way street.”"Recent data has now shown that as a matter of fact, there's also the added benefit to protect you from droplets and virus that's coming your way," Fauci said Tuesday on MSNBC."“You protect others," he added. "Their masks protect you. And your mask also protects you."In a separate interview on Tuesday, Fauci said that shut downs can be avoided.“We are not talking about shutting down,” Fauci told CNN’s Jake Tapper. “There is always that misunderstanding when we talk about public health measures. We are not talking about shutting down. We are talking about the four or five things I talk about all the time, wearing mask universally, keeping a distance, avoiding congregate settings indoors over outdoors and washing your hands.”Editor's note: A previous version of this story said "masks were best used for spreading the virus" when it should have said "masks were best used for preventing the spread of the virus." That has since been corrected. 2729

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