Rise of the Globular Clusters
With the centre of the Milky Way galaxy rising, July marks the time of year when globular clusters come into their own. The brighter ones include those with Messier numbers, such as M4, M5, M9, and M10. Stellarium and other planetarium programs will reveal a dozen or so nicely placed bright globular clusters high in the eastern sky in the early evening.
July represents the last chance you have to acquire good images of the brighter Virgo and surrounding galaxies, such as M 104 and M 83 which are now past the meridian in the west. Be sure to image these early in the evening while perhaps waiting for the the bright Milky Way globular clusters to rise higher in the east.
For those with bookings later in the evening, why not try imaging Pluto? A 30 second image will easily capture the faint dwarf planet, but you will need to revisit Pluto a few nights later in order to detect movement of the planet through what will be a dense field of stars. Pluto is well within the Sagittarius region of the Milky Way this month.
Winter marks the time of year when clear nights are most often used to acquire images of the bright Sagittarius nebulae: M16 (The Eagle Nebula), M17 (The Omega Nebula), M8 (The Lagoon Nebula) and M20 (The Trifid Nebula). All four will be virtually overhead by 10:30pm mid-month, and present an excellent opportunity to start gathering colour series data if you intend to create colour images. The H-a filter available on SPIRIT I will reveal much more detail in these hydrogen-rich emission nebulae, and can be used effectively during times of bright moon.
Speaking of the Moon, It will be full on July 4th, so the best times to image faint objects will be between July 11th and July 26th.
The Perth night sky Facing south at 7:30 pm on July 15.
(click on image to enlarge)