NASA's Dawn probe has been circling a dwarf planet known as Ceres for the past year, mapping its surface in extreme detail. Recent images captured from the spacecraft revealed a mysterious mountain on the dwarf planet, which the Dawn team has named Ahuna Mons.
"Ceres has defied our expectations and surprised us in many ways, thanks to a year's worth of data from Dawn. We are hard at work on the mysteries the spacecraft has presented to us," Carol Raymond, deputy principal investigator for the mission, based at NASA's Jet Propulsion Laboratory (JPL), said in a news release.
Dawn, the first ever spacecraft to visit a dwarf planet, has delivered a wealth of images and other data that opens the window to a previously unexplored dwarf planet, Ceres - the largest celestial body in the asteroid belt between Mars and Jupiter.
The new-found mountain, Ahuna Mons, first appeared as a small, bright-sided bump on the planet's surface as early as February 2015. However, this sighting was from a distance of 29,000 miles and before Dawn was captured into orbit, so further inspection was required.
From afar, Ahuna Mons looked to be pyramid-shaped, but upon closer inspection, it is best described as a dome with smooth, steep walls, NASA explained.
The latest Dawn Images captured an up-close shot of Ahuna Mons - about 120 miles closer than those taken in February 2015. It was these detailed images that revealed the mountain has a lot of bright material on some of its slopes, and less on others.
Images also suggest the mysterious mountain is about three miles high on its steepest side and has an average overall height of 2.5 miles.
"No one expected a mountain on Ceres, especially one like Ahuna Mons," added Chris Russell, Dawn's principal investigator at the University of California, Los Angeles. "We still do not have a satisfactory model to explain how it formed."
NASA scientists have started to identify other features on Ceres that could be similar in nature to Ahuna Mons, but none are as tall or well defined.
For example, Dawn captured images of at least 10 bright spots in Ceres' Occator Crater, which is located about 420 miles northwest of Auna Mons. However, it is not yet clear whether this bright material is the same as that found on the mountain.
"Dawn began mapping Ceres at its lowest altitude in December, but it wasn't until very recently that its orbital path allowed it to view Occator's brightest area. This dwarf planet is very large and it takes a great many orbital revolutions before all of it comes into view of Dawn's camera and other sensors," said Marc Rayman, Dawn's chief engineer and mission director at JPL.
The recent findings will present new images and other insights about Ceres at the 47th Lunar and Planetary Science Conference, during a press briefing on March 22 in The Woodlands, Texas.
