GETTING A GRIP ON GRAVITY Einstein's general theory of relativity explains gravity as a distortion of space (or more precisely, spacetime) caused by the presence of matter or energy. A massive object generates a gravitational field by warping the geometry of the surrounding spacetime.
Nicolle Rager Fuller
OLDER THAN IT LOOKS Some very old stars in the Milky Way, such as HE 0107-5240 (arrow), might be first-generation stars in disguise, a new study suggests.
COVERED WITH CROPS This false-color map of Ceres obtained by the Dawn spacecraft highlights the dwarf planet’s newly named features and its changing mineral composition. Red marks places that strongly reflect infrared light whereas blue regions reflect shorter wavelengths.