Take a tour of dwarf planet Ceres

Enigmatic bright spots within a crater on Ceres. Photo by NASA JPL on 6 June 2015 at 4400 kilometres altitude,
Resolution 410 metres per pixel.

NASA's Dawn robot entered orbit around dwarf planet Ceres on 6 March 2015.

It's the first spacecraft to visit two distinct interplanetary bodies, after first spending 14 months studying the smaller dwarf planet Vesta in 2011 and 2012.

The Dawn mission team are currently performing mapping orbits at around 13,600 kilometres out and navigational imaging about 5100 kilometres out. Once complete, Dawn will start edging into closer orbits.

NASA has combined images from these orbits to date into this wonderful flyover video released on 8 June:


At 15 seconds in, you'll see the mysterious bright spots (see photo above) in the base of a medium-sized crater that have so intrigued people the world over since they were first imaged months ago as Dawn approached Ceres. Nasa scientists are wondering if it could be a volcano, a geyser or cryo-volcano, shiny rock (as in glassy like molten from an impact), ice or salt.


At 28 seconds, there's a large crater on the terminus (the line between light and shadow) with several smaller craters inside it making it look like a bowling ball.

There are numerous light patches, presumably from more recent (geologically speaking) impacts, including a quite bright splash around a small deep crater at 54 seconds.

The wrap-up information points out that vertical elevations have been doubled and the starfield added in.

The vertical exaggeration would likely be by layering the images over the top of a radar terrain map, much the way Google Maps wraps Earth ground images over hills and buildings.

The starfield has to be added in because, although Ceres is a long way out, it is still vastly brighter than the surrounding stars. To get a correctly exposed image for Ceres itself, the exposure is far too short for the stars to show up. So the dwarf planet images themselves are masked over the top of a starfield layer. It's something astrophotographers have to do all the time. They take a photo of the Moon at a fraction of a second, then of the stars at several minutes (with a tracking mount), then mask the Moon over the starfield in Photoshop or similar. It's not cheating - it is just that a camera can't capture what your eye can see in the one shot. It's also why photos from the International Space Station always have milky black skies.

Is the starfield accurate? I'd be pretty sure it would be. NASA has a great application called Eyes on the Solar System, which lets you explore space and tag along with various bodies and spacecraft to see things just how they would see it. You can download NASA Eyes yourself for free.