Tonight – April 17, 2017 – look for the rather inconspicuous planet Mars quite low in your western sky as soon as darkness falls. You might see the nearby Pleiades star cluster with the eye alone – or you might need binoculars. Either way, Mars can guide you to the Pleiades … and the Pleiades can guide you to Mars.
Mars and the Pleiades cluster will fit (or nearly fit) in the same binocular field all this upcoming week. Mars and the Pleiades come closest together on the sky’s dome on or near April 22. Mars is a red planet, and there’s another reddish object nearby – the star Aldebaran – brightest star in the constellation Taurus the Bull. This star is about twice as bright as Mars is right now. From most places worldwide, Aldebaran shines higher in the sky and stays out later after dark than Mars does.
So, to find Mars and the Pleiades, look outside after sunset, as darkness is falling. Look first for ruddy Aldebaran – use our chart – and then find the red planet Mars and the Pleiades star cluster.
Mars and the Pleiades will follow the sun beneath the horizon by very early evening. Mars, though visible to the eye now, is a fading ember in our sky. It’ll soon be lost in the evening twilight (these recommended almanacs can tell you Mars’ setting time in your sky).
Remember, Mars and the Pleiades are not close together in space; they just happen to align right now, near the same point on the sky’s dome, as viewed from our earthly vantage point.
Also, after you’ve found Mars, turn in the opposite direction – toward the eastern half of the sky – to see the very bright planet Jupiter and bright star Spica, as depicted on the sky chart below.
Bottom line: During the week beginning April 17, 2017, Mars and the Pleiades cluster fit in the same binocular field. Look for them as soon as you can after sunset. They set shortly behind the sun.
Bruce McClure has served as lead writer for EarthSky's popular Tonight pages since 2004. He's a sundial aficionado, whose love for the heavens has taken him to Lake Titicaca in Bolivia and sailing in the North Atlantic, where he earned his celestial navigation certificate through the School of Ocean Sailing and Navigation. He also writes and hosts public astronomy programs and planetarium programs in and around his home in upstate New York.