
Monday morning, the solar system's innermost planet will begin a 5.5-hour march across the disc of the sun. All you need to see it are clear skies and access to a telescope with a sun filter.
(Image credit: Bill Ingalls/AP)

Monday morning, the solar system's innermost planet will begin a 5.5-hour march across the disc of the sun. All you need to see it are clear skies and access to a telescope with a sun filter.
(Image credit: Bill Ingalls/AP)