Dawn's contribution to Earth-based asteroid observations

One of the largest contributions Dawn has made to our understanding of asteroids is not just our understanding of Vesta itself, but the further refinement of our Earth-based observations now that we can compare them to those made much closer up. NASA has just written a press release on this subject, which corresponds with a paper written in the journal Icarus. The paragraph that best sums this up:

“A generation of scientific questions framed on the basis of lower-resolution data have been resolved by visiting Vesta with Dawn,” said Dawn Principal Investigator Christopher Russell, who is based at the University of California, Los Angeles. “We chose to go to Vesta because the ground-based telescopes and, later, Hubble told us it was an interesting place. That was true, but we needed Dawn to discern the mineral distribution and history of Vesta's surface. We now know how these data sets tie together and complement each other. This will help us in our telescopic studies of other members of our solar system.”

The press release doesn't mention how this will help us understand Ceres over the next year while Dawn is still too far away for up-close observations, but perhaps we will see something on that in the next few months. Ceres so far looks to us like this:

and this:

The larger and smaller white spot, along with that dark groove-looking formation near the bottom of the second image are some of the more intriguing puzzles, and perhaps this will help us better predict what they are over the next 15 or so months.

The press release shows two good examples of our Earth-based observations compared to those taken by Dawn. Vesta's topographic map is one of them. The Earth-based image is, of course, the one on top.