Out & About Spring 2019

STAR GAZING

Newbury Astronomical Society’s NIC FLEET presents a round-up of some of the night sky highlights to look out for during the spring months

Picture: Stellarium ,

Picture: Stellarium ,

The planets The planet Mars will be glowing like a tiny orange spark in the western evening sky over the next few months. Look for it from about 7pm on March 11, when it will be a little above and to the right of the thin crescent moon. As it gets dark on April 1, Mars will be close to the Pleiades star cluster, also known as the Seven Sisters, and on April 9 the crescent moon will be just above the red supergiant star Aldebaran, with Mars just a few degrees to the right (see illustration). The early morning sky will play host to the planets Venus, Jupiter and Saturn during the spring. Unfortunately, Venus is low down in the eastern sky as the sun rises and will be difficult to spot. Jupiter, however, rises at about 4am (GMT) at the beginning of March, but by the end of May it will rise at around 10pm (BST) and be visible most of the night. Look for it in the south on March 27, from about 4am onwards, when it will be very close to the waning moon. There’s another chance to find it near the moon before sunrise on April 23 and in the early hours of May 21. Saturn will also become more prominent during the spring months. It trails Jupiter by about 25 degrees – roughly the distance between your outstretched thumb and little finger, at arm’s length. It will be slightly lower than Jupiter and almost 16 times fainter, looking like a slightly golden star. At around 5am on March 29, the moon will be very close to Saturn, only a degree or so below it in the south east. If you miss this, look for it again on the morning of April 25, when the moon will be about five degrees to the right of Saturn.

The constellations Gemini and Leo At the beginning of March, the winter constellations of Taurus the Bull and Orion the Hunter can still be seen to the south in the early evening. However, by the end of April, they’ll have set by the time it gets dark. Instead, the Zodiac constellations of Gemini, the Twins, and Leo, the Lion, will take their place, heralding in the spring. The constellation of Gemini is easy to find. Simply follow an imaginary line through the two brightest stars in Orion, Rigel and Betelgeuse, for about twice the distance between them, and you’ll come to two bright stars, the twins Castor and Pollux. In Greek mythology Castor and Pollux were the sons of Queen Leda – but while Castor’s father was human, the father of Pollux was Zeus, the king of the Gods. This meant that Castor was mortal and could be killed, but Pollux was immortal so couldn’t die. The two half-brothers were inseparable, so that when Castor was killed in a fight, Pollux opted to share his immortality with his brother and Zeus placed them both in the sky as the constellation of Gemini. The star Castor is only 51 light years from Earth and, although it may look like a single star to the eye, it is actually a multiple system made up of six individual stars orbiting each other. Pollux, on the other hand, is only 34 light years from us and is a single star about twice as massive as our sun. In 2006, astronomers discovered that Pollux has a planet, approximately two-and-a-half times the mass of Jupiter, orbiting around it. Leo the Lion is one of the most ancient constellations recognised by the Mesopotamian civilisations more than 5,000 years ago. In Greek mythology, Leo was a savage beast whose hide was so thick no weapon could penetrate it. Realising this, the hero Heracles defeated it by strangling it with his bare hands and Zeus commemorated this feat by placing the Lion among the constellations. The brightest star in Leo is called Regulus, meaning ‘little king’. It is about 79 light years from us and is also a multiple star system – with at least four stars. On the evening of March 18, the moon will be just above Regulus in the south east and again, on May 12, the half-moon will be just to the left of Regulus. The constellation of Leo contains a number of bright galaxies, which can be seen with a medium-sized amateur telescope.

Picture: John Napper

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