Mars shines red next to blue Spica at sunset on Sept. 13

Mars will shine close to the blue star Spica at sunset on Sept. 13, but you’ll need a clear view of the western horizon to catch the colorful duo before they slip swiftly out of view.

Look west as the sun sets and you’ll find Mars less than 10 degrees above the summer horizon, with Spica shining to its lower left with the stars of the constellation Virgo. If you’re new to navigating the night sky, it’s useful to remember that the width of your clenched fist held at arm’s length equates to roughly 10 degrees, while the span of your middle three fingers measures approximately 5 degrees of sky.

Continue Reading