Sun, Moon & Mars

LADEE — pronounced “laddie” and short for Lunar Atmosphere and Dust Environment Explorer — was among the shortest-lived of NASA’s successful satellites. Launched on Sept. 7, 2013, it crashed onto the moon’s surface, as intended, on April 17, 2014, after six months orbiting the moon. Data collected by LADEE have already greatly expanded our understanding of the atmosphere of the moon and other bodies in the solar system; the spacecraft also made a number of unexpected discoveries, some of which were presented at the fall meeting of the American Geophysical Union (AGU) in San Francisco last December.

Two types of solar winds emanate from the sun: fast winds that travel at more than 700 kilometers per second, and slow winds that move at a mere 400 kilometers per second. As they pass by Earth on their way to the outer reaches of the heliosphere, these winds — composed of charged particles called plasma — can interact with the geomagnetic field and set off spectacular auroras. Now, a newly constructed solar map, published in a study in Nature Communications, has illuminated the sources and directions of the sun’s solar winds in greater detail than ever before.

NASA’s Curiosity rover found evidence that one or more large and long-lasting lakes probably filled Gale Crater in the planet’s warmer and wetter early history. While investigating the lower slopes of Mount Sharp recently at an outcrop called the Murray Formation, the rover photographed thick rock stacks featuring numerous layers of lithified sediment. Such stacks are typical of lake environments, where sediments slowly settle to the bottom and transform into rock over time.