Rocks that stood out as light-colored dots on the reddish-orange surface of Mars now are the latest evidence that areas of the small planet may have once supported wet oases with humid climates and heavy rainfall comparable to tropical climates on Earth.

Building on the University of Arizona's leadership in interferometry, a Steward Observatory-led team of astronomers probe mysterious "hot dust" around stars that has vexed astronomers for decades. The observed amounts are large enough to lead the team to believe the dust is being rapidly replaced, or some sort of mechanism extends its lifetime. 

A new study published in PNAS from researchers at The University of Texas at Austin is the first to define large river drainage systems on Mars. They outlined 16 large-scale river basins where life would have been most likely to thrive on the neighboring planet.

Every time a rocket is launched, tons of valuable materials are lost, and huge amounts of greenhouse gases and ozone-depleting chemicals are released into the atmosphere. Publishing December 1 in the Cell Press journal Chem Circularity, sustainability and space scientists discuss how the principles of reducing, reusing, and recycling could be applied to satellites and spacecraft—from design and manufacturing to in-orbit repair and end-of-life repurposing.