New Issue: Orbital Catastrophe Ahead? Read Now

Dawn Spacecraft Sets Sail for Dwarf Planet Ceres

On September 5th NASA's Dawn spacecraft left the asteroid Vesta and set sail for the dwarf planet Ceres, where it will arrive in 2015. John Matson reports

Join Our Community of Science Lovers!

In 2015, Dawn will rise over the dwarf planet Ceres. Not sunrise—this Dawn is a NASA spacecraft.

Since 2011, the craft has investigated the asteroid Vesta. In so doing, Dawn became the first probe to orbit an object in the asteroid belt between Mars and Jupiter. And a big object at that—Vesta is one of the largest asteroids out there.

On September 5th Dawn shoved off in pursuit of another first, and an even bigger target. In early 2015 it will arrive at Ceres, the largest object in the asteroid belt and one of the solar system’s so-called dwarf planets.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


No spacecraft has ever gotten an up-close look at a dwarf planet. But Dawn will spend several months in orbit around Ceres, and should test the theory that the mysterious world harbors a substantial amount of water ice beneath its crust.

Dawn uses a superefficient ion-propulsion engine. Ion engines deliver a tiny amount of thrust but sustain it to gradually accelerate a craft to high speeds. So the cruise to Ceres will take awhile, but it requires very little fuel, thus enabling one craft to accomplish two interplanetary firsts.

—John Matson

[The above text is a transcript of this podcast.]

Subscribe to Support Independent Journalism

Great science journalism requires human expertise, time, effort and creativity. And it costs money. That’s why I and the journalists here at Scientific American hope you’ll join our community.

When you subscribe, you are supporting staff and freelance journalists who are passionate about telling science stories that are true, important and compelling. Our editors and reporters are often experts in their fields, which means they understand the nuances of big discoveries and can untangle the breakthroughs from the hype. With a subscription, you are also supporting rigorous fact-checking to ensure the words we publish are precise and accurate. And you’re supporting original illustrations, graphics and photos that bring you closer to an advanced laboratory, an ice sheet in Antarctica or a space mission in orbit. You’re helping us craft other types of high-quality journalism as well: Our newsletters are carefully written, edited and curated by staffers you have or will come to know and love. Our Science Quickly podcast is based on original reporting, collaboration with editors and scientists and exacting production.

Subscriptions keep this engine running so we can continue to deliver thoughtful, rigorous and independent science journalism to you. In an era of viral misinformation, this work is crucial. If you value what we do, I hope you’ll consider joining us as a subscriber

Thank you,

Jeanna Bryner, Editor in Chief, Scientific American

Subscribe