Saturn mission goes in for final close-ups
THE summer is rapidly approaching and the night sky will begin to stray further and further from true darkness.
At the start of May, there are only three or four hours of truly dark skies (astronomically speaking) and this quickly reduces as we approach June.
At this time of year, the Sun never quite sets low enough beneath the horizon and often leaves us in a state of twilight. Not until early August will the night skies be truly dark.
The planet Jupiter remains very prominent in the night sky this month and is well placed for observation throughout the night.
Watch out tomorrow when the Moon will make a close pass by Jupiter. With binoculars, it is possible to observe all four of the large Galilean moons orbiting around Jupiter.
Of Io, Europa, Ganymede and Calisto, only Europa is smaller than our own Moon, with the largest Ganymede having a diameter 50 per cent greater than the Moon. Both Ganymede and Saturn’s largest moon Titan have diameters which are larger than the planet Mercury. Ganymede contains ice and Titan also has a dense atmosphere. If orbiting the Sun directly, instead of around their host planets, they would likely be classed as planets in their own right.
The planet Saturn is making a return to the night sky and is visible low down on the southern horizon. By the end of May it will be observable at midnight, gradually becoming an evening object as the season passes.
Saturn’s brightness can vary according to our view of its famous ring system. The rings are currently seen wide open and so are reflecting more sunlight across space toward us, making Saturn brighter in the sky to the naked eye.
Having spent a decade exploring Saturn and its moons, the successful Cassini Huygens spacecraft mission is undertaking a “grand finale”. It will be making close orbits of the planet, producing spectacular images before burning up in its atmosphere.
Even though our window of observation becomes shorter with the return of the summer twilight, there is still plenty to see in the night sky. The Moon will be easily visible in early May and then we’ll have slightly darker skies after the Moon has left the evening sky.
The Eta Aquarid meteor shower peaks this weekend. Even though it’s not always the most easily visible meteor shower, you could still see an increase in meteor activity. From a dark location, free from light pollution, the summer Milky Way will start to become visible rising in the east after midnight. One of the brighter sections of Milky Way runs through the constellation of Cygnus.
Cygnus is a large pattern, but is easy to spot as it looks roughly like a large cross of five stars. It is sometimes possible to see structure in the clouds of stars and dust that make up our home galaxy.