Opposites attract the eye in July’s night sky

The magnificent Sombrero Galaxy M104, a lenticular galaxy in the constellation Virgo, is an estimated 29 million light-years from Earth. Photo by MPAS member Steve Wilkins

This month we will see our two gas giants at opposition: Jupiter on July 14 and Saturn on July 21. Opposition is when the sun is on the opposite side of the sky from the outer planet in question – or, to be more technical, when the sun and the planet are exactly 180 degrees apart in the sky. It is also when the planet is at its general closest position to Earth.

On July 5 we can see Jupiter shining bright close to the moon, with Saturn close to the moon the following night. July 11 will see Mars and the moon close together, with the bright star Aldebaran close by on July 12. Then on July 17 a thin crescent moon will be visible near Venus in the morning.

Sitting high in the southern skies, Scorpius is easy to spot this month. Nearby is the constellation Sagittarius, which is famous for the ‘Teapot’ asterism formed by some of its brightest stars. When you look towards Sagittarius and Scorpius, you are peering towards the centre of the Milky Way galaxy. This whole region is full of rich and beautiful star fields, which are great to explore using binoculars. At this time of the year the constellation Sagittarius offers some exceptional deep-sky objects. The globular cluster M22 is visible to the naked eye if you have good observing conditions. The Lagoon Nebula, or M8, lying above the spout of the ‘Teapot’, is a glowing cloud of gas.

Other famous deep-sky objects in Sagittarius are visible through a telescope, including the Trifid Nebula, or M20. Beside Sagittarius, Scorpius contains the bright open clusters M6 and M7, which remain high in the sky this month. To the north in the constellation Serpens Cauda, the Tail of the Serpent, lies the open cluster M16 in the much fainter Eagle Nebula.

By Nerida Langcake
This article appeared in the July 2020 issue of the Mornington Peninsula Magazine.