Space
A sea of polygons on Mars, and the weather that made them
The shapes only form when ground ice freezes and thaws in cycles. Mars, at some point, had seasons that mattered.
Science
Research, climate and what the instruments are seeing.
Astronomy
The first moon outside our solar system may already be found
A Jupiter-mass object orbiting a brown dwarf fits every test for an exomoon except confirmation.
Space
The Moon's far side is quietly overturning the textbook
Samples from the hemisphere we never see do not match the hemisphere we do. The early Solar System looks messier than taught.
Climate
Oxygen is draining out of the world's water
Oceans, lakes, rivers and coasts, all in the same direction. Deoxygenation is the climate story that does not photograph well.
Skywatching
The best sky in years arrives on 12 August
A solar eclipse, the Perseid peak, Venus at dichotomy and the Milky Way at its cleanest — on the same date.