With all the excitement of the recent solar eclipse and transit of Venus across the face of the Sun behind us, the starry heavens have a few more cosmic treasures for skywatchers.
Scan the evening skies towards the high eastern horizon this month and explore that ancient classical Greek hero Hercules. While the constellation’s stars are not the brightest, four do make a distinctive wedge-shaped trapezoid of stars marking this superhero’s chest – known as the ‘Keystone’. Look carefully with even binoculars and you’ll find one of the greatest showpieces in the entire night sky; the Great Hercules Cluster or M13.
M13 is a globular cluster made up of a swarm of a half a million stars packed into a ball, stretching over 100 light years across. On a dark moonless night binoculars will easily show it as a fuzzy grey ball, while small telescopes will begin to resolve the edges of the cluster into individual stars.
Located 24,000 light years away, it is one of about 150 globular clusters scattered in a halo around the outside of our own Milky Way galaxy. The light from M13 that you see tonight left the cluster when Earth was still locked in its last ice age.
Meanwhile much closer to home, the planets are putting on their own sky show. The first couple of weeks in June the most challenging of all naked-eye planets makes an appearance very low in the northwestern sky just after sunset. The innermost planet will slowly be rising higher as the planet moves farther away from the Sun – which will be easily visible if you keep an eye on the planet from night to night.
Mercury will position itself within the constellation Gemini in June and on June 21st will sitting on top of the waxing crescent Moon. The cosmic pair will be separated by about 6 degrees – a little more than the width of your three middle fingers at an outstretched arm.
Then as an extra observing challenge on June 24 the little planet will appear to line up with the two brightest stars Castor and Pollux very low towards the horizon just after sunset. A pair of binoculars will help you track down all three.
The red coloured Mars is high in the southwest evening sky and appears between two bright, white stars. To its right is 78 light year distant Regulus. While to the far lower left of Mars you will find the ringed jewel of the solar system, Saturn in the constellation Virgo. The bright star below Saturn is 263 light year distant Spica.
Not sure which is which? The moon will conveniently point the way starting on June 25,when it first pays a visit to the Red Planet, and then on June 27 and 28 it will glide below Saturn, Spica stellar pair.
Finally for those early bird skywatchers, the two brightest planet – Jupiter and Venus – which earlier this season dominated the evening sky will now appear in the predawn twilight very low towards the eastern horizon by mid- June. Look for the razor-thin crescent moon in a super-close encounter Jupiter low in the east at dawn on June 17.
Posted in Constellations, Planets, Solar System, Stargazing, stars | 1 Comment »