Stonehenge May Be an Ancient Solar Calendar

Ancient sanctuary used by Roman soldiers nearly 2,000 years ago found in the Netherlands

The massive, strange Comet K2 is touring the solar system, surprising scientists as it goes

David Lunt revolutionized amateur astronomy by introducing the first hydrogen-alpha solar telescopes for consumers in the late 1990s. H-alpha filters had been available before, but they required electronic temperature control to maintain their narrow passpands, making them cumbersome to use