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Our Expert Voices conversation about the 2017 solar eclipse.

One big question scientists still have about the Sun is why its corona, the outer atmosphere, is so hot — millions of degrees — while the surface below is only thousands! Eclipses provide unique opportunities to get higher quality and speed images than are normally available, either from space or from the ground. During the total eclipse, we're using telescopes mounted on the noses of NASA's WB-57 research jets to observe the solar corona. By observing waves in it and measuring their direction, size, and speed, we hope to better understand how energy is transported up into the corona. With two jets flying at 50,000 feet, we'll get 7-and-a-half minutes of totality compared to only 2-and-a-half on the ground.

What it means: Studying how the corona is formed and how it evolves will lead to better understanding "space weather" hazards like flares and coronal mass ejections that can impact Earth and damage satellites, interrupt GPS and radio, and knock out power grids.

Other voices in the conversation:

Go deeper

House grants waiver for retired Gen. Lloyd Austin to lead Pentagon

Defense Secretary nominee Lloyd Austin Photo: Chip Somodevilla/Getty Images

The House voted 326-78 on Thursday to grant retired Gen. Lloyd Austin a waiver to lead the Pentagon, clearing the way for the Senate to confirm President Biden's nominee for defense secretary as early as this week.

Why it matters: Austin's nomination received pushback from some lawmakers, including Democrats, who cited a law that requires officers be out of the military for at least seven years before taking the job — a statute intended to reinforce the tradition of civilian control of the Pentagon.

Amanda Gorman steals the show on Inauguration Day

Data: NewsWhip; Chart: Axios Visuals

Poet Amanda Gorman by far generated the most average interactions on social media on Inauguration Day, according to exclusive data from NewsWhip.

Biden unveils "wartime" COVID strategy

Biden signs executive orders on Jan. 21. Photo: Mandel Ngan/AFP via Getty Images

President Biden on Thursday signed a slew of executive orders to address the coronavirus pandemic, including an interstate face mask mandate and an order to renew supplies of PPE, testing materials and vaccines through the Defense Production Act.

Why it matters: The stakes are highest for Biden’s vaccination effort. Several states cannot keep up with demand.