The solar system is the gravitationally bound system of the sun and the objects that orbit it. Of the bodies that orbit the sun directly, the largest are the four gas and ice giants and the four terrestrial planets, followed by an unknown number of dwarf planets and innumerable small solar system bodies. Of the bodies that orbit the Sun indirectly—the natural satellites—two are larger than Mercury and one is nearly as large.
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Simulate a visit to the red planet with the Mars 2020 Perseverance Rover. This 3D interactive experience lets you explore various locations on the martian surface. See closeup images the rover has taken and view key points of interest. It's the next best thing to being there and certainly far safer!
Explore key moments in Earth’s transformative history as continents drift and climate fluctuates over 4.6 billion years. The Smithsonian presents a series of interactive snapshots of the earth. From its toddler years during the Hadean period, when its surface was mostly molten, to the mostly unidentifiable landmasses of the future earth, 100 million years from now.
We'll likely never see the Earth's core, but we can make educated guesses about what it's like down there. Nearly as hot as the sun's surface and under impossibly high pressure, the inner Earths extreme conditions make it impossible to explore. Yet, seismic waves during earthquakes, volcanic eruptions, and light waves from the sun provide fascinating insights about our planet’s mantle, crust, and core.
The Lunar and Planetary Institute provides assorted resources about the red planet, Mars. Review this basic 101 level introduction and get to know our solar system neighbor. Learn about Mars' planet-wide dust storms, staggeringly high mountains (six of which dwarf Mount Everest), and whether there's water there below the surface.
Sometimes called the Earth's twin, Venus certainly isn't an identical one. The second brightest object in the nighttime sky, right after the Moon, while Venus has a central iron core and a rocky mantle like Earth's, that's where the similarities end. Discover these and other facts in this video.
Get to know Venus, one of our closest planetary neighbors. Despite being named for the Roman goddess of love—and the only one named for a woman—Venus is an searingly hot place covered in thick carbon dioxide clouds, volcanoes, and warped mountain ranges. Yet it has a lot to teach us about planet Earth.
Solar eclipses are some of the most awe-inspiring natural phenomena a person can witness on Earth. But when's the next one? Track all future solar eclipses, their projected paths of totality around the world, and more with this interactive, data-rich visualization of the dramatic world event.
The age of Earth has fascinated humanity for centuries, but it was not until the discovery of radiometric dating that scientists came close to an accurate estimate. This four-minute video from PBS explores the history and science behind determining Earth's age, explaining how geochemists utilized radiometric dating techniques to arrive at a figure of approximately 4.565 billion years. Improvements in radiometric dating methods have shifted our estimates of Earth's age from thousands of years old to billions of years old. As scientists continue to refine these estimates, radiometric dating remains a key tool for understanding Earth's geological history.
The solar system's smallest planet was named after the Roman god Mercury (the Greeks' Hermes), the swift messenger, as the ancients observed Mercury's quick revolutions around the Sun—a result of its proximity to the Sun's gravity. With a 3,000-mile diameter, Mercury is roughly the size of the continental United States. A terrestrial (primarily solid land) planet like Earth, Mercury's inner core is filled with more iron than Earth's. As the iron cooled, Mercury shrunk, possibly contributing to the planet's diminutive shape. Its thin atmosphere allows for major temperature swings throughout its day. Watch a three-minute video overview here.
Is there a massive ninth planet on the edge of our solar system? Many of our solar system's most distant objects tend to swing out in one direction, hinting at evidence for a previously unknown ninth planet potentially larger than Earth. This theoretical planet's orbital period is estimated to be roughly 20,000 years, revolving around the sun at a distance of 60 billion miles. Experts break down the evidence in this quick video.
From roughly 60 miles above the Earth's surface to farther than light has traveled during the entire age of the universe, space has captured human imagination for millennia. Explore the final frontier with the best resources curated from across the internet.