Starwatch: spectacular line-up of three bright planets

Starwatch 05 Mar 2018 planetary alignment

Early risers may have already noticed the beautiful planetary alignment taking place in the south-east before dawn. The bright planets of Saturn, Mars and Jupiter are strung out in a line. Saturn sits in Sagittarius, Mars in Ophiuchus and Jupiter in Libra. The colours of the planets are particularly notable. Jupiter’s bright clouds give it a brilliant white light, whereas Mars is distinctly red to the eye. Completing the trio, Saturn is a pale yellow that betrays the more muted tones found in its atmosphere. Just below this line of planets, filling in the gap between Mars and Jupiter, is the red giant star Antares. This alignment alone is worth keeping an eye open for but starting on 7 March the waning gibbous moon joins the tableau, making it even more special. The chart shows the view at 05:30 GMT on 8 March when the Moon is in the constellation Scorpius.