Where, exactly, did our oceans come from? New research suggests that asteroids might have both delivered and removed lots of water – and that Earth itself might have locked it away deep inside.
Samples taken from two drill holes on Mars support the idea that Mars lost a whole lot of water fairly early in its history.
A highly successful spacecraft has ended its mission after returning nearly a decade of data on Earth’s nearest planetary neighbor.
Venus and Mercury draw closer together this week until they are less than 1° apart in the evening of January 10th. Plus, learn when you can see Comet Lovejoy in a moonlight-free sky.
The latest Comet Lovejoy should reach 4th magnitude in the second and third weeks of January, when it will be nicely placed high in the moonless dark for your binoculars or telescope. It’ll by visible to the unaided eye under dark-sky conditions — if you know exactly where to look.
Our monthly podcast offers the key highlights for stargazing in January: where to find bright stars and planets, and a special look at the Pleiades star cluster.
In a quartet of high-quality videos, Sky & Telescope editors offer newcomers solid, objective tips on how to buy, use, equip, and care for new telescopes.