NASA’s Dawn spacecraft has continued its survey of the dwarf planet Ceres this year, discovering rock-bound ice hidden just beneath the airless world’s rugged surface and a handful of icy outcrops inside craters in the northern hemisphere, raising hopes that Ceres could have once held a buried habitable ocean of liquid water.
The brightest area on Ceres stands out amid shadowy, cratered terrain in a dramatic new view from NASA’s Dawn spacecraft, taken as it looked off to the side of the dwarf planet. Dawn snapped this image from about 920 miles (1,480 kilometres) above Ceres in its fifth science orbit, in which the angle of the Sun was different from that in previous orbits.
By tracking subtle changes in the motion of NASA’s Dawn spacecraft, scientists have mapped the variations in Ceres’ gravity for the first time, providing clues to the dwarf planet’s internal structure. The new data suggest that Ceres has a weak interior, and that water and other light materials partially separated from rock during a heating phase early in its history.
Ceres is covered in countless small, young craters, but none are larger than 175 miles (280 kilometres) in diameter. To scientists, this is a huge mystery, given that the dwarf planet must have been hit by numerous large asteroids during its 4.5 billion-year lifetime. Where did all the large craters go?
Scientists with NASA’s Dawn mission have identified permanently shadowed regions on the northern hemisphere of dwarf planet Ceres. Most of these areas likely have been cold enough to trap water ice for a billion years, suggesting that ice deposits could exist there now. These permanently shadowed regions could be colder than those on Mercury or the Moon.
Following its historic first-ever flyby of Pluto, NASA’s New Horizons mission has received the green light to fly onward to an object deeper in the Kuiper Belt, known as 2014 MU69. The spacecraft’s planned rendezvous with the ancient object — considered one of the early building blocks of the solar system — is 1 January 2019.
The brightest area on Ceres, located in the mysterious Occator Crater, has the highest concentration of carbonate minerals ever seen outside Earth, according to a new study from scientists on NASA’s Dawn mission. The results suggest that liquid water may have existed beneath the surface of Ceres in recent geological time.
Using data from NASA’s Lunar reconnaissance Orbiter, scientists have discovered two geologically young craters — one 16 million, the other between 75 and 420 million years old — in the darkest regions of the Moon’s south pole. Such craters provide valuable information on the frequency of collisions in the solar system.