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."

Go deeper

American carnage

Protesters race up a hill to avoid tear gas in Philadelphia, June 1. Photo: Mark Makela/Getty Images

The list of victims has swiftly grown since George Floyd died in police custody just eight days ago.

The big picture: Protests against police brutality have turned into a showcase of police brutality, with tear gas and rubber bullets deployed against crowds. The police have the arsenals at their disposal, but we're also seeing law enforcement officers becoming targets.

McConnell blocks resolution condemning Trump's actions against peaceful protesters

Senate Majority Leader Mitch McConnell (R-Ky.) blocked a resolution introduced by Minority Leader Chuck Schumer (D-N.Y.) on Tuesday that would have condemned the use of tear gas and rubber bullets against peaceful protesters outside the White House on Monday in order to allow President Trump to walk to St. John's Church.

What they're saying: "Justice for black Americans in the face of unjust violence, and peace for our country in the face of looting, riots, and domestic terror. Those are the two issues Americans want addressed," McConnell said on the Senate floor.

George W. Bush breaks silence on George Floyd

Goerge Bush in Michigan in 2009. Photo: Bill Pugliano/Getty Images

Former President George W. Bush (R) wrote in a statement Tuesday that he and his wife, Laura, are "anguished" by the death of George Floyd, and said that "it is time for America to examine our tragic failures."

Why it matters: It's a stark juxtaposition when compared to fellow Republican President Trump's response to current civil unrest. While Trump has called for justice in Floyd's death, he's also condemned protestors and threatened to deploy military personnel if demonstrations continue.