With South Africa beginning to feel the onset of winter, the night sky will become prominent as the weather conditions become more and more settled. If one comes prepared for the cold nights, winter is one of the best times to view the stars. Less moisture in the air means that the view will be less distorted and allow for clearer images, especially through telescopes. However, the next few months will allow for some impressive views with a simple pair of binoculars!
Here are some phenomena to keep your eyes peeled for in the next 3 months:
Our Solar System’s largest planet is easily visible in the eastern skies after sunset. Currently Jupiter can be found in the constellation of Virgo and is unmistakable due to its brightness. Depending on its orbital position, Jupiter is an average of 700 million kms from Earth, yet even amateur telescopes can pick up the cloud bands on the surface. 1,300 Earths can fit inside Jupiter and thus it exerts a huge gravitational influence on its surroundings and in turn actually protects Earth from space debris like small comets and asteroids by altering their orbits
- The Galilean Moons
When viewing Jupiter through 8x or 10x binoculars, you will see up to 4 pin pricks of light around it. These are Jupiter’s largest Moons, Io, Europa, Ganymede and Callisto and are coined the Galilean Moons due to their discovery by Galileo in 1610. This marked a massive shift in understanding of the cosmos as it was the first evidence that other worlds also had objects orbiting them. This discovery and others paved the way for the scientific shift from a Geocentric model of the solar system (Earth at the centre) to the Heliocentric model (Sun at the centre).
Found in the constellation of Carina in the southern skies, Canopus is the 2nd brightest star in the night’s sky although it is not visible from the northern hemisphere. Despite being fainter than Sirius, it is actually much brighter in terms of its actual brightness. Sirius is a mere 8.6 light years from us whilst Canopus resides 700 light years away! It is also used in space travel as a marker to adjust a shuttle’s position in relation to the background stars
If you can locate Jupiter, it is currently in the constellation of Virgo. Despite the association of the virgin, Virgo is generally considered to be referring to the goddess of justice, Dike from Greek mythology. Whilst Virgo has little of interest for those viewing with binoculars, anyone with a telescope should be able to find some of the more than 2000 galaxies contained in its surrounding area, known as the Virgo cluster.
Arcturus can be found in the constellation Bootes that should be seen rising in the north east. It is the 4th brightest star in the sky and the brightest to be found in the northern celestial hemisphere. The name comes from the Greek ‘Arktouros’ meaning ‘Bear Watcher’ referring to the constellation being associated with the herdsman for the Great Bear, or Ursa Major, that is adjacent to it in the sky.
- Hercules and M13
Looking east from Bootes, one can see the huge constellation of Hercules. The centre of the constellation is depicted by 4 stars making a box shape and along one of those edges a fuzzy blob can be seen with binoculars. This is M13, known as the Great Globular Cluster. This old collection of stars resides in the halo of the Milky Way about 22,000 light years away and consists of approximately 300,000 gravitationally interacting stars!
Ophiuchus is unknown to many as a constellation but is more than worth a mention, not just because of its size. Despite being found on the ecliptic (the path taken by the Sun across the sky) it was not included as one of the signs of the zodiac. In fact, the Sun spends more time in Ophiuchus than it does in neighbouring Scorpius! Ophiuchus depicts the great Greek healer, Aesulapius. According to myth Aesulapius discovered the secret of resurrection and was banished to the heavens before he became too powerful. A descendent of Aesulapius is Hippocrates and it is from this association that the ‘Hippocratic Oath’ taken by doctors today is derived.
- The Jewel Box (NGC 4755)
The Jewel Box can be located in the Southern Cross, very close to Beta Crucis. It is an Open Cluster which means it is a group of ‘related’ stars that were all created at the same time form the same gas cloud, and travel through space as a group. The name ‘Jewel Box, was derived from the many different colours of the stars within the cluster and was named by English astronomer William Hershel who described it as ‘a casket of variously coloured precious stones’.
Blog written by Ben Coley