David McComas has a favorite “astrosphere,” the environment created by a star’s stellar wind as it buffets the surrounding interstellar medium. It belongs to a star named Mira.…

Terri Randall’s hope when she makes films about space exploration—like Chasing Pluto, for example, or Death Dive to Saturn—is that viewers share scientists’ excitement. That…

Do you ever feel like someone is watching you? They could be. And I’m not talking about the odd neighbors at the end of your street.This summer, at the Carl Sagan Institute at Cornell…

Our human world is soaked in light. For starters there are the 100,000 trillion photons arriving every second at every square centimeter of Earth’s dayside surface, after racing…

On the dark night of March 13, 1781, William Herschel settled down in his garden observatory in Bath, England, for a routine night of observing stars, when he noticed something out…

It seemed inevitable that Elon Musk would eventually get into a Twitter war over whether Mars can be terraformed. When you’re on Twitter, he told Businessweek in July, 2018, you’re…

In the late afternoon of May 5, SpaceX’s Elon Musk tweeted, “Starship landing nominal!” Musk is not known for understatement. But seeing that stainless steel behemoth soar was,…

You know what the plot of a show called CSI: Chicxulub would be? Finding out what killed the dinosaurs, of course. There’s now no question that the scene of the “crime” was the…

Suppose aliens existed, and imagine that some of them had been watching our planet for its entire four and a half billion years. What would they have seen? Over most of that vast timespan,…

In the early 1960s, during the space race, neither American nor Soviet scientists really knew where planets like Mars or Venus were—especially at the accuracy and precision essential…