Science: All Eyes on Halley's

Swinging within about 55 million miles of the sun every 76 years, Halley's comet has been an object of awe since what may have been the first reported sighting, by Chinese astronomers in 240 B.C. But when this cosmic snowball of ice and dust—with a nucleus between 3 and 6 miles across and a tail millions of miles long—streaks across the sky in 1986, it will be greeted for the first time by five spacecraft. In the vanguard of an international effort to study the comet, the Soviet Union recently launched two 4.5-ton unmanned...

Want the full story?

Subscribe Now

Subscribe
Subscribe

Get TIME the way you want it

  • One Week Digital Pass — $4.99
  • Monthly Pay-As-You-Go DIGITAL ACCESS$2.99
  • One Year ALL ACCESSJust $30!   Best Deal!
    Print Magazine + Digital Edition + Subscriber-only Content on TIME.com

Learn more about the benefits of being a TIME subscriber

If you are already a subscriber sign up — registration is free!