ESA’s Solar Orbiter should solve the longstanding puzzle about why the Sun’s outer corona is so much hotter than its surface.

The Sun emitted a strong solar flare on June 19, peaking at 7:50 p.m. ET. NASA’s Solar Dynamics Observatory captured an image ...

An active region of the Sun, known as sunspot 4114, has just produced an X1.9-class flare. This event, which occurred on June ...