This diagram shows the various parts of the Sentinel Space Telescope, an asteroid-monitoring observatory planned by the B612 Foundation. Nearly 9,000 near-Earth asteroids are known today, and more ...

SOFIA isn’t the first time NASA has conducted astronomy from an airplane. Planetary scientist Gerard Kuiper pointed a 12-inch telescope out the window of a modified Learjet in 1968. Seven years later, ...

Albert Einstein's long-lost telescope, forgotten for decades in a Jerusalem storage shed, goes on display this week after three years and $10,000 spent restoring the relic. The old reflecting ...