NASA/JPL-Caltech/UCLA

There is new evidence to support the hypothesis that all stars are "born" with at least one "sibling" — including our sun.

Why it matters: "Our work is a step forward in understanding both how binaries form and also the role that binaries play in early stellar evolution," said UC Berkeley astronomer Steven Stahler.

Two explanations for star pairs:

  1. The two or three stars that are commonly found at the center of planetary systems fall into place together after they form.
  2. The stars at the center of a planetary system are "born" together as "siblings" — this is the favored hypothesis, and the one the new study supports.

The finding: Scientists looked at data from a dust cloud's radio waves in the Perseus constellation that had a host of baby stars. They found that the younger class of stars were closer to their "partners," while some drifted apart as they got older. The scientists then created several simulations of different ways the stars could form. The model that had stars and their twins forming at the same time produced numbers closest to what is observed.

Throwback: Since the 80s, people have speculated that the sun used to have a twin star that shared the center of our universe, even going so far as to name it "Nemesis" and blame it for the extinction of the dinosaurs.

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Americans reflect on Independence Day amid racism reckoning

A Black Lives Matter banner and a United States flag on the facade of the U.S. embassy building in Seoul, South Korea. Photo: Simon Shin/SOPA Images/LightRocket via Getty Images

America's leaders are rethinking how they view Independence Day, as the country reckons with the historic, unequal treatment of people of color during a pandemic which has disproportionately affected nonwhite Americans.

Why it matters: The country’s legacy of racism has come into sharp focus in the weeks of protests following the death of George Floyd while in Minneapolis police custody. From Confederate statues to Mount Rushmore, Americans are reexamining the symbols and traditions they elevate and the history behind them.

Updated 13 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Aïda Amer/Axios

  1. Global: Total confirmed cases as of 7 p.m. ET: 11,031,905 — Total deaths: 523,777 — Total recoveries — 5,834,337Map.
  2. U.S.: Total confirmed cases as of 7 p.m. ET: 2,788,395 — Total deaths: 129,306 — Total recoveries: 790,404 — Total tested: 34,213,497Map.
  3. States: ICU beds in Arizona's hot spot reach near capacity.
  4. Public health: The states where face coverings are mandatory Fauci says it has been a "very disturbing week" for the spread of the coronavirus in the U.S.
  5. Economy: The economy may recover just quickly enough to kill political interest in more stimulus.
15 hours ago - Sports

Washington Redskins to review team name amid public pressure

Photo: Patrick McDermott/Getty Images

The Washington Redskins have announced they will be conducting a review of the team's name after mounting pressure from the public and corporate sponsors.

Why it matters: This review is the first formal step the Redskins are taking since the debate surrounding the name first began. It comes after weeks of discussions between the team and the NFL, the team said.