It’s the largest, most massive planet in the Solar System. But what’s the real story behind all the impacts on Jupiter? One of the most terrifying prospects here on Earth is […]

And one of our planets has the orbiting moons to prove it. Despite the dangers posed to planet Earth by a comet or asteroid strike, our Solar System is actually an […]

What makes Uranus and Neptune-like worlds so fascinating? If you only knew. What do we really know, and what mysteries are left to solve, about the outer worlds of our Solar […]

A case for looking beyond the planetary scientist’s (or even the astronomer’s) definition. Ever since 2006, when the International Astronomical Union (IAU) officially defined the term planet — introducing the term ‘dwarf […]

The two planets most suited for habitability had very different fates. At last, scientists know why. Imagine the early days of our Solar System, going back billions of years. The Sun […]

Our outer Solar System, from Jupiter to Neptune, isn’t unique after all. In the early 1990s, scientists began detecting the first planets orbiting stars other than the Sun: exoplanets. The easiest […]

Our planet is rare, precious, and fragile. It’s up to all of us to be its steward. With the advent of rocketry and spaceflight, our cosmic perspective changed forever. The very […]

If you think we’ve done a great job with planet-finding so far, just wait until you learn what’s possible with microlensing! When we think about finding planets in the Universe, […]

In all the Universe, there’s only one Earth. But can we find the other worlds that are like ours? Even though the ingredients for life have been confirmed to be practically […]

It’s rare but spectacular when the Moon passes in front of another planet. Here’s how to see it. From our perspective on Earth, the night sky appears virtually unchanged with the […]

It’s a rare occasion for orbits to align so perfectly. Enjoy the sights this Tuesday. On Tuesday, February 19th, the Moon will reach perigee, its closest point of approach to planet […]

The first planet beyond ‘naked eye’ astronomy will pass within just 1° of Mars. Although there are eight major planets in the Solar System, most of us never see Uranus or […]

Only 8 worlds make the astronomical cut as planets. Here are the 10 fascinating bodies that didn’t make it. Astronomically, bodies within the Solar System must achieve three criteria in order […]

Although the great Martian dust storm of 2018 may have ended its life, its accomplishments will live on forever. Note: This article was originally published on January 25, 2019 on Forbes. […]

All the other planets have craters, icecaps, clouds, or a rich, banded structure. But not Uranus. The eight major planets of the Solar System all possess their own unique features. The […]

We’d never flown past or imaged a small, isolated Kuiper belt object before. Here’s what we know so far. As 2018 ended and 2019 began, NASA’s New Horizons flew past its […]

If you photograph the Sun at the same time every day, you get a bizarre figure-8 shape: an analemma. Here’s why. At any time of day, you could theoretically set up […]

With thousands of discovered planets around stars beyond our own Sun, why haven’t we found the next Earth? Over the past 30 years, astronomers have gone from zero known extra-solar planets […]

It may have been captured by Neptune since it formed, but Triton remains king of the Kuiper belt. Our Solar System is arguably the most well-studied corner of the Universe, with […]

All the planets, asteroids, and Kuiper belt objects out there all point to the same conclusion: it’s giant impacts or no moons at all. Out of all the rocky planets […]

The Solar System’s outermost, undisputed planet wasn’t discovered until the 19th century. Here’s how you can easily find it yourself this December. There’s no greater scientific thrill than discovering something […]

We can’t help but wonder if it’s habitable, or even inhabited, but the evidence isn’t there for it. Every star that fills the night sky carries along with it one of […]

Space may be enormous, but collisions are inevitable. Here’s what happens when they occur. The Universe as we know it has been around for nearly 14 billion years: plenty of time […]

Mars will never look as big as the full Moon. But it isn’t even the biggest planet. From humanity’s perspective, the Sun and Moon always dominate Earth’s skies. The Moon and […]

How ‘special’ are we for life to have survived and thrived the way it did? While there are hundreds of billions of stars in our galaxy, many with Earth-sized planets at […]

Finding the ingredients for life is a very different prospect than finding the products of life. Perhaps the greatest quest in science today is to find life that originated beyond Earth. […]

Sedna could be the very first known object from the Inner Oort Cloud. But time is running out to create and launch a mission. In 2003, scientists discovered an object beyond […]

One of the night sky’s most famous sights isn’t what it appears to be. Perhaps the most famous sight of a dying star is the Ring Nebula, known since 1779. The […]

Congress refused the majority of Trump’s proposed cuts to NASA’s budget. But many uncertainties remain. On March 21st, 2018, both branches of Congress passed the United States’ Consolidated Appropriations Act, […]

The possibilities were almost limitless, so why does everything line up? Our Solar System is an orderly place, with the four inner planets, the asteroid belt, and the gas giant worlds […]