The Night Sky This Month

Northern HemisphereIan Morison tells us what we can see in the Northern Hemisphere night sky during December 2019.The PlanetsJupiter, shining on the 1st at magnitude -1.8 and with an angular size of 32 arc seconds, can be seen very low in the southwest as darkness falls at the start of December but, soon after, will be lost in the Sun's glare. Jupiter lies in the southeastern part of Ophiuchus and is heading towards the southernmost part of the ecliptic so, as it appears in the twilight, will only have an elevation of ~6 degrees. With its low elevation, atmospheric dispersion will take its toll and an atmospheric dispersion corrector would greatly help to improve our views of the giant planet and it four Gallilean moons.Saturn will be seen west of south as darkness falls at the start of the month. Then, its disk is ~16 arc seconds across and its rings - which are still, at ~24 degrees, nicely tilted from the line of sight - spanning some 36 arc seconds across. During the month its brightness remains +0.6 wit