Even if you’re not habitually an early riser in the British Isles, you may wish to set your alarm for 5am BST on Monday, 14 September to see an attractive conjunction occurring low in the eastern sky. Dazzling Venus and the almost 26-day-old waning crescent Moon lie in the constellation of Cancer, both within the same low-power binocular field of view as the beautiful open star cluster known as Praesepe, the Beehive Cluster, or Messier 44.
Keen-eyed UK observers will notice that the Moon lies close to the magnitude +4.6 star gamma (γ) Cancri, otherwise known as Asellus Borealis, at this time. Although no occultation of the star occurs as seen from the British Isles, the graze line crosses France, passing through Laval and just north of Paris.
Venus dazzles at magnitude -4.2 on the morning in question with a westerly elongation from the Sun of 43 degrees. Telescopically, the planet has a 65 percent illuminated disc spanning 17½ arcseconds. Magnitude +3.9 star delta (δ) Cancri, otherwise known as Asellus Australis, lies a degree to the upper left of Venus in binoculars and low-power, erect-image telescopes.