The Night Sky This Month

Northern HemisphereThe Night SkyIan Morison tells us what we can see in the Northern Hemisphere night sky during October 2018.The PlanetsJupiter - Jupiter can be seen low in the west soon after sunset at the start of the month. It shines at magnitude -1.8 (falling to -1.7 during the month) and has a disk some 32.6 (falling to 31.4) arc seconds across. Jupiter's equatorial bands, sometimes the Great Red Spot and up to four of its Gallilean moons could be visible in a small telescope but its low elevation will greatly hinder our view. Saturn - Saturn will be visible in the south-east at an elevation of ~14 degrees after sunset at the beginning of October. Its disk has an angular size of 16.5 arc seconds falling to 15.7 during the month. Its brightness reduces from +0.5 to +0.6 magnitudes as the month progresses. The rings were at their widest last year but are still well open and spanning ~2.5 times the size of Saturn's globe. Saturn is moving slowly eastwards in Sagittarius. Sadly, atmospheric dispersion will