NASA, ESA, and J. Lowenthal (Smith College)

Scientists have observed what Albert Einstein once said was impossible to see — distant starlight bending around a massive star outside our solar system. The discovery with the Hubble Space Telescope is the first direct detection of a key prediction of Einstein's general theory of relativity.

Go deeper: When Einstein was developing the general theory of relativity 100 years ago, he predicted that gravity would act like a magnifying lens when a distant star passed by a closer object, brightening and bending the starlight. But "there is no hope of observing this phenomenon directly" because stars are so far apart, he wrote in Science in 1936.

What's new: Scientists have been able to detect the bending of light around our own sun. (They first confirmed the effect, for instance, in a 1919 eclipse.) But, until now, they have not been able to observe the phenomenon known as gravitational microlensing directly.

In the new study, astronomers were able to pinpoint a moment in time when a white dwarf star and a second star were being observed in such a fashion that lensing could be seen for the first time. They were able to then determine the mass of the white dwarf star – which had only been possible in theory until now.

Why it matters: Because the majority of all stars are destined to become white dwarfs at some point, the ability to determine their mass (and, thus, their fate) gives scientists more information on the makeup of our galaxy and allows them to better understand the history and evolution of galaxies like our own.

The details: Einstein predicted a ray of light passing near a massive star like a white dwarf to be deflected by twice the amount that would ordinarily be expected based on what we know of gravity. He also posited that, if we were able to observe distant starlight from two stars in the foreground and background, the gravitational microlensing would result in a perfect circle of light – known as an "Einstein ring." Scientists didn't observe a perfect circle in the new study, but in searching through 5,000 stars they found two that were out of alignment – essentially resulting in an asymmetrical Einstein ring. That, in turn, allowed them to measure the mass of the white dwarf star.

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Updated 21 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Politics: The swing states where the pandemic is raging — Pence no longer expected to attend Barrett confirmation vote after COVID exposure.
  2. Health: 13 states set single-day case records last week
  3. Business: Where stimulus is needed most.
  4. Education: The dangerous instability of school re-openings.
  5. States: Nearly two dozen Minnesota COVID cases traced to 3 Trump campaign events
  6. World: Restrictions grow across Europe.
  7. Media: Fox News president and several hosts advised to quarantine.

Republicans and Dems react to Coney Barrett's Supreme Court confirmation

President Trump stands with Judge Amy Coney Barrett after she took the constitutional oath to serve as a Supreme Court justice during a White House ceremony Monday night .Photo: Tasos Katopodis/Getty Images)

President Trump said Judge Amy Coney Barrett's Senate confirmation to the Supreme Court and her subsequent taking of the constitutional oath Monday was a "momentous day," as she she vowed to serve "without any fear or favour."

  • But as Republicans applauded the third conservative justice in four years, many Democrats including Speaker Nancy Pelosi (Calif.) warned of consequences to the rush to replace the late Justice Ruth Bader Ginsburg ahead of the Nov. 3 election, with progressives leading calls to expand the court.
Ina Fried, author of Login
1 hour ago - Science

CRISPR pioneer: "Science is on the ballot" in 2020

Photo: "Axios on HBO"

In her three decades in science, Jennifer Doudna said she has seen a gradual erosion of trust in the profession, but the recent Nobel Prize winner told "Axios on HBO" that the institution itself has been under assault from the current administration.

  • "I think science is on the ballot," Doudna said in the interview.

Why it matters: That has manifested itself in everything from how the federal government approaches climate change to the pandemic.

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