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."

Go deeper

Biden: The next president should decide on Ginsburg’s replacement

Joe Biden. Photo: Drew Angerer / Getty Images

Joe Biden is calling for the winner of November's presidential election to select Ruth Bader Ginsburg's replacement on the Supreme Court.

What he's saying: "[L]et me be clear: The voters should pick the president and the president should pick the justice for the Senate to consider," Biden said. "This was the position the Republican Senate took in 2016 when there were almost 10 months to go before the election. That's the position the United States Senate must take today, and the election's only 46 days off.

Trump, McConnell to move fast to replace Ginsburg

Photo: Alex Wong/Getty Images

President Trump will move within days to nominate his third Supreme Court justice in just three-plus short years — and shape the court for literally decades to come, top Republican sources tell Axios.

Driving the news: Senate Majority Leader Mitch McConnell and Senate Republicans are ready to move to confirm Trump's nominee before Election Day, just 46 days away, setting up one of the most consequential periods of our lifetimes, the sources say.

Updated 5 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 10 p.m. ET: 30,393,591 — Total deaths: 950,344— Total recoveries: 20,679,272Map.
  2. U.S.: Total confirmed cases as of 10 p.m. ET: 6,722,699 — Total deaths: 198,484 — Total recoveries: 2,556,465 — Total tests: 92,163,649Map.
  3. Politics: In reversal, CDC again recommends coronavirus testing for asymptomatic people.
  4. Health: Massive USPS face mask operation called off The risks of moving too fast on a vaccine.
  5. Business: Unemployment drop-off reverses course 1 million mortgage-holders fall through safety netHow the pandemic has deepened Boeing's 737 MAX crunch.
  6. Education: At least 42% of school employees are vulnerable.