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Fortunately, we won’t have to wait till next month for more photos. NASA plans to pause the probe twice on the way down to shoot and send fresh images.

"We have looked for a plume, and thus far, we have not found it," UCLA astronomer Christopher Russell, the Dawn mission's principal investigator, told NBC News in an email. "But we have these bright spots that have the reflectivity of ice, and whose spectrum of reflected light is similar to that expected from ice. So ice is a good bet."

The released image shows the mysterious lights to the right of the enlarged area but no highlights of them. NASA says that this set of photos called OpNav9 was “the ninth and final set of Dawn images of Ceres taken primarily for navigation purposes.” That sounds like a convenient but vague excuse for pointing the camera away from the lights that NASA has been calling “ice.” NASA’s poll of what the rest of us think the lights are had “Other” winning by an avalanche over ice.

"The general consensus on the team right now is that water is definitely a factor on Ceres, but that the spots themselves are more likely to be just highly reflective salt, rather than water,"

[B]ased on the spectral data the team did get, Russell said, the spots "really don't look like mounds of ice."

Russell said that a “haze” was visible in this crater at certain times of day, and that it was seen more than once. A follow-up question, the only one there was time for, established that the haze was confined to the crater itself.

The bright spots "are possibly subliming, or they're providing some atmosphere in this particular region of Ceres," Russell said. The haze covers about half of Occator crater and does not extend beyond the hole's rim, he added.

Well, we do. We're now, today, taking data at our second best resolution (December 2015 will be even closer at 235 miles above the Ceres surface), and the images have come in. We were just ready to submit with the press release written and the images of the bright spots were in our press release. And then, we realized that one of the investigators had sent in a paper to the publication Nature, which required an embargo for us not to talk before publication — and the paper is about the bright spots, making an interpretation of what the bright

"The irregular shapes of craters on Ceres are especially interesting, resembling craters we see on Saturn's icy moon Rhea," said deputy mission chief Carol Raymond from Nasa's Jet Propulsion Laboratory in California. "They are very different from the bowl-shaped craters on Vesta."

During the 2015 meeting of the European Planetary Science Congress on Sept. 28, principal investigator for the Dawn mission Dr. Chris Russell stated that “we believe that this is a huge salt deposit, and to me that tells me that this is an active surface.”
That is, some geologic process is at work to generate those bright salt deposits… they are all from Ceres.