Nov 8, 2017

A star has lived five lives

A composite image of a supernova remnant. Photo: MPIA / NASA/ Calar Alto Observatory

Supernovae are usually the death of stars but for at least one, explosion didn't mark the end, scientists report today in Nature.

What they saw: Supernova iPTF14hls was first observed in 2014. Unlike other supernovae that typically shine for about 100 days before fading, this one — about 500 million light-years away — grew brighter and then dimmer five times over 600 days. Even more peculiar, archives showed another explosion was observed in the same location in 1954.

Why its happening: Unclear. According to one theory, repeated explosions can occur in stars 95 -130 times more massive than the Sun. They, too, would end in a supernova and ultimately collapse into a black hole.

Yes, but: The supernova's constant temperature doesn't fit with the theory and it released more energy than theory predicts.

What's next: Supernova iPTF14hls may finally be fading, reports Lisa Grossman in Science News. "I am not making any more predictions about this thing," study author Iair Arcavi told Grossman. "It surprised us every time."

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Joe Biden places second in Nevada caucuses, ahead of Pete Buttigieg

Democratic presidential candidate and former Vice President Joe Biden a Nevada Caucus watch party in Las Vegas on Saturday. Photo: Ronda Churchill/AFP via Getty Images

Former Vice President Joe Biden secured second place in the Nevada Democratic caucuses with former Southbend Mayor Pete Buttigieg third, according to NBC News projections Sunday.

By the numbers: With almost 88% of precincts reporting, Biden has 20.9% of the Nevada votes and Buttigieg has 13.6%.

Flashback: Bernie Sanders wins Nevada caucuses

Editor's note: This is a developing news story. Please check back for updates.

Sanders reveals free childcare plan for preschoolers

Democratic presidential candidate Sen. Bernie Sanders speaks during a campaign rally on Saturday in El Paso, Texas. Photo: Cengiz Yar/Getty Images

Democratic presidential candidate Sen. Bernie Sanders announced on CBS' "60 Minutes" Sunday a new plan to guarantee free child care and pre-kindergarten to all American children from infancy to age four.

Details: In the wide-ranging interview, Sanders told Anderson Cooper he planned to pay for universal childcare with a wealth tax. "It's taxes on billionaires," he said.

Exclusive: Trump's "Deep State" hit list

Illustration: Aïda Amer/Axios. Photos: WPA Pool/Getty Pool, Drew Angerer/Getty Staff

The Trump White House and its allies, over the past 18 months, assembled detailed lists of disloyal government officials to oust — and trusted pro-Trump people to replace them — according to more than a dozen sources familiar with the effort who spoke to Axios.

Driving the news: By the time President Trump instructed his 29-year-old former body man and new head of presidential personnel to rid his government of anti-Trump officials, he'd gathered reams of material to support his suspicions.