Set your alarm clocks extra early this weekend to see a rare triple-conjunction involving three of the major planets.

Shortly before dawn on December 9th, Mercury, Mars, and Jupiter form a triangle roughly 2° wide. To see them, look low in the east-southeast horizon. Binoculars will help you see all three members, but a small telescope will add a few additional treats to the scene: Jupiter's Galilean moons and the bright double star-system Beta Scorpii just 19 arcminutes above Jupiter.

The next morning on December 10, the entire grouping gathers even closer, fitting within a 1.1° field. You can catch Beta Scorpii just 9 arcminutes northeast of Mercury. Mars will be about a degree to the right of Mercury and Jupiter, which are about 1/3 of a degree apart from each other.

Photographers hoping to capture the scene should look for a clear, low south-southeast horizon. According to calculations by Steve Albers, this will be the best observable triple-conjunction of the bright planets until 2029, so don't miss it!