New theoretical modelling of the ancient history of the Earth and the Moon suggests that the giant collision that spawned our natural satellite may have left Earth spinning very fast, and with its spin axis highly tilted. The simulations give new insight into the question of whether planets with big moons are more likely to have moderate climates and life.
Dark matter, the mysterious substance that constitutes most of the material universe, remains as elusive as ever. Although experiments on the ground and in space have yet to find a trace of dark matter, six or more years of data from NASA’s Fermi Gamma-ray Space Telescope has broadened the mission’s dark matter hunt using some novel approaches.
Since its detection in 2014, the brown dwarf known as WISE 0855 has fascinated astronomers. Only 7.2 light-years from Earth, it is the coldest known object outside of our solar system. Now, a team led by astronomers has succeeded in obtaining strong evidence for the existence of clouds of water or water ice — the first such clouds detected outside our solar system.
An international team of researchers have used the W. M. Keck Observatory to confirm the existence of the most diffuse class of galaxies known in the universe. These Ultra Diffuse Galaxies (UDGs) are nearly as wide as our own Milky Way galaxy — about 60,000 light-years — yet harbour only one percent as many stars.
Hitting the jackpot is one thing, but if you hit the jackpot four times in a row you might wonder if the odds were somehow stacked in your favour. A group of astronomers led by Joseph Hennawi of the Max Planck Institute for Astronomy have found themselves in exactly this situation. They discovered the first known quasar quartet: four quasars, each one a rare object in its own right, in close physical proximity to each other.