Three’s Company: Asteroid 87 Sylvia and her two moons

Among the thousands of asteroids roaming the inner solar system, 87 Sylvia stands out. New observations reveal that two smaller asteroids orbit this 280-kilometer-wide rock. It’s the first asteroid found to be accompanied by two moons.

MOONSCAPES. The asteroid 87 Sylvia and its two moons appear in this illustration, along with the sun (far left).