They shine with a brightness that stands in stark contrast with the rest of Ceres’ surface. Here’s our best look yet at the bright spots inside Occator crater.
The latest image comes from NASA’s Dawn spacecraft as it orbits Ceres, a dwarf planet situated inside the asteroid belt between Mars and Jupiter. Scientists hope Dawn can shed some light on how Ceres formed and get a better picture of what our early solar system looked like.
Before I touch on the bright spots, let’s take a deeper look at Occator crater. Before it was dubbed Occator, this crater was known as “Region A” from observations by the W.M. Keck Observatory on Mauna Kea, Hawaii.
The crater’s name is a helper god to Ceres, a Roman goddess of agriculture. Occator is “he who harrows.”
Occator is famous for the mysterious bright white spots that lie on its crater floor, but scientists do know a bit more about it. It has a diameter of 57 miles and is about 2.5 miles deep. Scientists also note that the rim of the crater is nearly vertical in some places. It’s a big crater, but it’s nowhere near the biggest, diameter wise.
The largest crater on Ceres is called Kerwan and has a diameter of 176 miles.
You can notice the crater is shallow for its size and doesn’t have a central peak. Its crater floor is also marked by dozens of other craters. You can clearly see the left outline of the crater in the image. Scientists believe this crater is older than much of Ceres surface because of the craters and other features overlapping it
While Occator is the most famous of Ceres’ craters, it’s just the ninth largest one.
The Bright Spots
What are they? It is a question on everyone’s mind, along with how did they originate? The answer? We still don’t know. And that makes it all the more intriguing.
“Dawn has transformed what was so recently a few bright dots into a complex and beautiful, gleaming landscape,” said Marc Rayman, Dawn’s chief engineer and mission director. “Soon, the scientific analysis will reveal the geological and chemical nature of this mysterious and mesmerizing extraterrestrial scenery.”
The leading candidates are ice or salt. In July, Nature’s Alexandra Witze wrote an article about a mysterious haze appearing above the bright spots. “At noontime, if you look at a glancing angle, you can see what seems to be haze,” Christopher Russell, a planetary scientist at the University of California, Los Angeles, said at the time. “It comes back in a regular pattern.”
This haze bolsters the case for the bright spots being ice, but the Dawn science team won’t have a definitive answer until they receive geological and chemical data.
Here’s a bonus video from NASA’s Jet Propulsion Laboratory showing the bright spots and the topography of Occator crater.