June 15 – June 22, 2021: Brilliant Evening Star Venus shines in the west-northwest after sunset. It continues to close the distance to Mars. Venus shines from Gemini, beneath Castor and Pollux. Mars marches eastward in Cancer, approaching the Beehive star cluster.
June 18 – 19, 2021: The waxing moon is moving through Virgo. On June 18, it is near Porrima. The next evening, the moon is above Spica.
June 15, 2021: The Pleiades star cluster returns to the morning sky. You may have observed the star cluster in the east-northeast during morning twilight.
2021, June 23: Through a binocular, Mars is in front of the Beehive star cluster this evening. The stars Gamma Cancri (γ Cnc) and Delta Cancri (δ Cnc) are in the same binocular field of view as Mars and the cluster.
June 20, 2021: The sun reaches the summer solstice mark in the sky, to signal the beginning of astronomical summer in the northern hemisphere.
June 17, 2021: At mid-month, bright Jupiter and Saturn are in the southern sky before sunrise. Saturn is retrograding in Capricornus. Jupiter’s eastward direction is slowing as it turns westward to retrograde beginning June 21.
June 15 – June 17. 2021: The evening waxing moon passes Leo the Lion. On June 15, the moon is near Regulus and Eta Leonis. The next evening, June 16, the lunar orb is between Regulus and Denebola. On June 17, the moon is beneath Denebola.
Mid-June, 2021: As morning twilight begins – quite early this time of year – the great winged horse is in the south-southeast. The Great Square of Pegasus is made of moderately bright stars. The horse’s neck and head extend toward the south. A star cluster is off the tip of the horse’s nose.
August 18, 2021: During bright twilight, five planets and the moon are in the sky simultaneously after sunset. This is a challenging observation made with the assistance of a binocular or spotting scope. Mercury and Mars are at their closest in the west, with brilliant Venus to the upper left. The moon, Saturn, and Jupiter are in the southeastern sky. The Mercury – Mars conjunction is the closest until 2032.
June 11 – 14, 2021: After the solar eclipse, the crescent moon returns to the western sky after sunset appearing with Evening Star Venus on June 11. Each evening the crescent waxes and appears higher in the sky. The crescent is near Mars on June 13.