Medically reviewed by Brendan Camp, MD Key Takeaways Comedones are bumps on your skin caused by blocked hair follicles, leading to blackheads and whiteheads.Use oil-free and non-comedogenic products ...

Here’s how it works. A large solar prominence (bottom right) bursts from the sun while a plasma tornado (top right) rages nearby. (Image credit: Maximilian Teodorescu) A giant solar tornado and a ...