This photo of the asteroid Vesta will likely be the first of many for NASA probe Dawn.

The spacecraft is on its way to orbit the asteroid, the solar system’s second largest, and recently returned its first picture of the giant rock.

Vesta is technically a protoplanet — a large body that nearly formed into a planet. About 330 miles in diameter, it moves in the asteroid belt between Mars and Jupiter.

So far, it looks like a glowing orb — but that’s just for now. The spacecraft is scheduled to move into Vesta’s orbit in July.

Dawn will then move on to explore the asteroid Ceres — the only body in the belt more massive than Vesta. The spacecraft should be arriving at Ceres around 2015.

Here’s what the Dawn mission is all about, according to NASA:

Gathering information about these two icons of the asteroid belt will help scientists unlock the secrets of our solar system’s early history. The mission will compare and contrast the two giant bodies shaped by different forces. Dawn’s science instruments will measure surface composition, topography and texture. Dawn will also measure the tug of gravity from Vesta and Ceres to learn more about their internal structures. The spacecraft’s full odyssey will take it on a 5-billion-kilometer (3-billion-mile) journey, which began with its launch in September 2007.

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