The stars in late spring free, (Image: Martin Lunn)
MAY is the first month of the year when Orion is completely absent from the sky. The great Hunter has disappeared below the horizon and of the other winter stars only Capella in Auriga, together with Castor and Pollux in Gemini, are still visible.
The North Star can still be found by using the pointer stars in the Plow. These are the two stars furthest from the handle. A line drawn from the star on the right through the left and continuing for some time across the sky reaches the North Star.
The North Star, or Polaris, to give it its proper name, is the last star of the Little Herd, a much fainter version of the more common Herd. Any hints of fog in the sky make it difficult to spot the pattern of the Little Crested except for the red colored star Kocab, which is one of the last stars of the blade.
Another interesting star to try to locate is Thuban in the constellation Draco the Dragon. Thuban is halfway between Mizar, the central star on the handle of the Horcrux, and Kocab, often called the ‘Guardian of the Hole’. Tuban is famous for being a faint star, but it was the North Star when the great pyramids were built in Egypt. The pyramids were aligned with Tuban rather than Polaris.
The position of the North Star changes over a long period of time due to the Earth’s wobble. If you spin an image of just about to fall over, the handle appears to draw a circle. This, of course, only takes a fraction of a second.
If you imagine the Earth as that spinning top, a line projecting from the North Pole onto the Earth will draw a circle in the sky. It takes 23,500 years for the Earth to decay once. So, around 2000 BCE the North Star, today Polaris, and in about 14,000 CE will be the bright star Vega.
Waiting for the northern sky, this is a good time to search for the stars that form Draco the Dragon. Draco is formed by a long curve of stars that spirals around the North Star. The dragon’s head is formed by a quadrant of four stars at the end of this line of stars and is easy to find because it is close to the bright star Vega, one of the stars of the Summer Triangle. The four stars are not bright but they are quite distinctive. Harry Potter fans reading this may recognize the name ‘Draco’ used by JK Rowling to create Draco Malfoy, one of Harry’s enemies.
Last month I explained how to find Arcturus by following the curve of the Tribune’s handle. If we then continue with the curve around it it will focus on Spica in Virgo the Virgin, which is now just to the south and can be seen at its best this month. Regulus in Leo the Lion can be found at the bottom of the prominent reverse issue which shows the lion’s head and is now very prominent in the south. Spica and Regulus are also at their best this month.
One last star to mention that can easily be seen on a late spring evening is Cor Caroli, the only bright star in the constellation Canes Venatici, the Hunting Dogs.
Although it is not as bright as the stars that form the Plow it is still easy to see. This star can be found under the handle of the Horde. Canes Venatici hunting dogs are sometimes shown on a leash in the hands of Bootes the Herdsman. Sir John Flamsteed, the first Astronomer Royal, added the constellation to the sky, and Cor Caroli was named in honor of the murdered monarch, King Charles I.
The Planets in May: Mercury which was visible so brilliantly in April low in the western sky just after sunset and too close to the Sun in the sky is now visible. This also applies to the two giant planets Jupiter and Saturn.
If we want to look for the planets of the naked eye, we have Mars that can be seen in the southwest. The red planet can be seen below the crescent moon on May 24, but Mars is outshined by Venus or as it is sometimes called, the ‘Night Star’, which apart from the Moon is the brightest object in the sky evening Venus can be seen in the constellation Gemini the twin. It appears under the two bright stars Castor and Pollux. If the weather is clear between May 22 and May 24 the crescent moon will be seen passing Venus.
Meteor Showers: On the night of 5/6 May the Eta Aquarid Meteor shower will be at its peak. These meteors are the remnants of Halley’s Comet, one of the most famous of all comets.
Unfortunately the meteor shower will be low in the sky so not many meteors will be visible. It is best seen from countries much further south than Britain. However, if you are out that night, especially in the early hours of May 6th and you see a meteor, you will likely have seen a small part of Halley’s comet burning up in the atmosphere.
Phases of the Moon: Full Moon 5; Last quarter 12; New Moon 19; First Quarter 27 .
The Full Moon in April is known as the Flower Moon. The flowers in the parks and gardens are becoming abundant now for everyone to see.
The next meeting of the Earby Astronomical Society will be held on Friday, May 26 in All Saints Church, Earby from 7.30pm – 9pm. The speaker will be Martin Lunn MBE FRAS and the title of the talk is ‘Astronomy in Yorkshire – Halifax’. All are welcome.