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NASA’s Dawn spacecraft has been sending back images of the dwarf planet Ceres for several months now, but the latest are the clearest ones to date. Dawn entered close orbit of Ceres back on March 6th. The planet is now believed to be 584 miles in diameter (down from a pre-mission estimate of 590). It’s located in the asteroid belt between Mars and Jupiter, which makes it the only dwarf planet inside the orbit of Pluto. This new set of photos, taken from an orbital altitude of 915 miles, show off Ceres’ tall, conical mountain, as well as some braided fractures and the appearance of crater formation.

“Dawn is performing flawlessly in this new orbit as it conducts its ambitious exploration. The spacecraft’s view is now three times as sharp as in its previous mapping orbit, revealing exciting new details of this intriguing dwarf planet,” said Marc Rayman, Dawn’s chief engineer and mission director at NASA’s Jet Propulsion Laboratory, Pasadena, California, in a statement.

A mountain ridge (near the lower left) lies in the Urvata crater. The image at the top of this article shows a 4-mile-high conical mountain. (Credit: NASA/JPL-Caltech)

Currently, Dawn can record and send back images in 11-day cycles, each of which consists of 14 orbits. NASA said the spacecraft is using its framing camera to map the surface of Ceres for 3D modeling, and that each image has a resolution of 450 feet per pixel and represents less than one percent of the surface. The spacecraft is also using its visible and infrared spectrometer to collect mineral data.

This video, released a few weeks ago, lets you tour the surface of Ceres and get a closer look at the mysterious bright spots in the Occator crater and the aforementioned cone-shaped mountain:

That mountain should have roughly the same four-mile elevation as the highest mountain in the US: Mount McKinley in Denali National Park, Alaska.

“This mountain is among the tallest features we’ve seen on Ceres to date,” said Dawn science team member Paul Schenk, a geologist at the Lunar and Planetary Institute, Houston, in a statement from JPL. “It’s unusual that it’s not associated with a crater. Why is it sitting in the middle of nowhere? We don’t know yet, but we may find out with closer observations.”

As for the bright spots, the jury is still out; so far the craft has not found evidence consistent with ice. “The science team is continuing to evaluate the data and discuss theories about these bright spots at Occator,” said Chris Russell, Dawn’s principal investigator at the University of California, Los Angeles. “We are now comparing the spots with the reflective properties of salt, but we are still puzzled by their source. We look forward to new, higher-resolution data from the mission’s next orbital phase.”

NASA’s Dawn spacecraft heads toward the dwarf planet Ceres in an artist’s conception. (Credit: NASA/JPL-Caltech)

Beginning in late October, the craft will begin spiraling down to an even lower orbit of just 230 miles. Maybe by then we’ll finally get some answers about those bright spots. Ceres has some other mysteries as well; for example, it’s the only asteroid known to have been rounded by its own gravity, thanks to its extreme mass.