SLOW FADE Tabby’s star dims strangely over the course of days and years. Explanations have ranged from a destroyed planet to a ring of debris (shown in this artist’s illustration), but new studies suggest that clouds of dust or a strange stellar cycle might be more likely.
HEATED PAST From around 4.25 billion years ago to at least as late as 2.5 billion years ago, the moon had a magnetic field, which dwindled in strength over time, a new study finds.
Goddard Space Flight Center/NASA
EXOMOONS AHOY Moons like the ones in this illustration could be a haven for life outside the solar system.