Welcome to the University of Texas Skywatchers' Report for May 15th through the 21st.
The moon is at third quarter on the night of Friday the 19th.
There are still several bright planets visible in the evening and morning skies. In the west at nightfall are Mars and Saturn, with the twin bright stars of Gemini Castor and Pollux between and to the right of the two planets. Saturn is the higher and brighter of the two and sets around 1 a.m. Venus is rising at 4:30 a.m. and is visible in the twilight before sunrise.
Jupiter is taking over as the dominant planet throughout the night. It is rising about an hour before sunset, so it is well placed in the east for evening viewing. If you have good binoculars or any size telescope, you should be able to see the four largest moons of Jupiter, collectively called the Galilean satellites, but individually are Io, Europa, Callisto and Ganymede. These are the four dots that Galileo saw going around Jupiter with his small telescope 400 years ago. The moons move quickly enough around Jupiter that you can see them move over just a few hours time, and they will move a lot from night to night. Observer’s handbooks and charts will often include a chart of where to find the moons from night to night, as well as timing charts for the Great Red Spot. Online versions are available at skyandtelescope.com/observing/objects/planets/
There is currently no public viewing on the UT campus telescope. Summer viewing will start in June. Please call back in the next few weeks for more information.
Thank you for calling the University of Texas Skywatchers' Report.