Have you ever had a question even the Internet couldn’t answer? Some members of the Illinois State University community did. And we put Illinois State University’s faculty experts to work answering their inquiries.

What are those two shining lights on planet Ceres?

—Mark Wesolowski ’91, Chicago

Astronomers, like all scientists, are explorers. Visiting new worlds guarantees unexpected mysteries, with each new discovery initially challenging to explain. The two bright spots, in a crater on the dwarf planet Ceres, are the latest example. Finding and solving such mysteries is one of the reasons we explore the far reaches of our solar system.

The bright spots on Ceres are sunlight reflected from the edge of an impact crater. Yet what reflects this light? Is it piled ice or salt, recently churned up from beneath the surface of Ceres by a meteor impact? Or is the ice reflected by something else? Only further exploration of Ceres will tell.

We see a similar phenomenon on Umbriel. This is one of the heavily cratered moons of Uranus. There, irregular patches of sunlight shine from the Wunda Crater. Perhaps the bright spots on Ceres will help us better understand what is also happening on Umbriel.

I hope that the Dawn space probe reveals the source of these lights as the probe gets a closer look at Ceres. We might discover that water, in the form of buried ice, is common throughout our Solar System. Then again … maybe not. Solving mysteries like this is why we explore the many and varied worlds that orbit our sun.

Tom Willmitch, director, Illinois State University Planetarium

To submit a question for one of Illinois State’s experts, email Kevin Bersett or tweet the question to @ISUResearch. Please provide your name, affiliation with the University if applicable, and town of residence.

2 thoughts on “Ask an expert: What are those two shining lights on planet Ceres?

  1. Chico says:

    that was no answer at all.