A strange, gargantuan wall of acid-filled clouds on our neighboring planet Venus has been spotted by a hobbyist astronomer. This structure, known as the Venus Cloud Discontinuity, is around 5,000 ...

Earth, Mars and Venus all looked pretty similar when they first formed. Today, Mars is dry, cold, and dusty; Venus has a hot, crushing atmosphere. Why did these sibling planets turn out so different?

The only way to find better answers — on phosphine, Venus’s volcanic cadence, its cataclysmic transformation — is to revisit the planet. Fortunately, a fleet of new spacecraft is set to do ...