We can’t tell from Earth, but the Sun isn’t a fixed shape. Instead, like an ocean, the flow of its plasma causes constant movement. The changeability of stars can result in some interesting shapes, including one that’s just been discovered looking like a teardrop.
HD 74423 is a binary system, where two stars orbit around each other. We already know of many stars that do this, including several that have oval orbits. Gravity squeezes and flattens these stars as they get closer together, then relaxes as they move away from each other.
That’s not what happens with HD 74423, though. This system has a circular orbit, and one star is constantly pulled into a teardrop by the other. The tip of this shape is ‘fluffier’ than the rest of the star, so it is more affected by internal changes like the Sun’s. Scientists hope that studying this unique system could help us understand what happens in the middle of stars.
Lachlan Writes Science 