A stellar explosion known as a nova that was detected in 2000 formed a two-lobed shell of material ejected from the star. Shaped like a bow tie, it continues to swell at great velocity. But, curiously, the coat of ejecta flowing outward from the star lacks hydrogen, the most common gas in the universe. [More]

A NASA rover mired in soft soil on Mars made its first escape attempt in months Tuesday, but the maneuver lasted less than a second before safety precautions shut it down. [More]