Like cosmic ballet dancers, the stars of the Pleiades cluster are spinning, but all at different speeds. By watching these stellar dancers, NASA’s Kepler space telescope has helped amass the most complete catalogue of rotation periods for stars in a cluster. This information can provide insight into where and how planets form around these stars, and how such stars evolve.
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.
New findings using data from NASA’s Mars Reconnaissance Orbiter show that gullies on modern Mars are likely not being formed by flowing liquid water. This new evidence will allow researchers to further narrow theories about how Martian gullies form, and reveal more details about Mars’ recent geologic processes.
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?
The European Space Agency’s orbiting XMM-Newton X-ray observatory has proved the existence of a ‘gravitational vortex’ around a black hole. The discovery, aided by NASA’s NuSTAR mission, solves a mystery that has eluded astronomers for more than 30 years and will allow them to map the behaviour of matter very close to black holes.
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.
Water is a hot topic in the study of exoplanets, including “hot Jupiters” close to their parent stars that can reach a scorching 1,100 °C, meaning any water they host would take the form of vapour. Hot Jupiters have been found with water in their atmospheres, but others appear to have none. NASA scientists wanted to find out what the atmospheres of these giant worlds have in common.
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