NASA's twin Voyager probes are nearly 45 — and facing some hard decisions

What's the biggest group of animals ever recorded on Earth?

Saturn’s rings are so much brighter than Jupiter's because they're made mostly of ice particles replenished by many small moons embedded in the rings. Jupiter’s dim, thin rings, by contrast, are made mostly of dust shed from a few small moons, and the large Galilean moons destroy any large rings.

SOAR High School Student Wins NASA Armstrong Scholarship