Shooting stars and a sturgeon moon - the night sky in late summer with Martin Lunn

At the present time only the Geminids in December and the Quadrantids in January produce more meteors. Some meteors will be seen a few days before this date and a day or so after.

Many people know meteors as shooting stars, but they have nothing at all to do with stars. They are tiny grains of dust that burn up when they enter the Earth’s atmosphere.

They travel at speeds ranging from 20 to 50 miles per second and we see the result of their destruction in the form of a brief streak of light across the sky.

Although a few sporadic meteors can be seen on any night of the year, there are periods when many can be seen, and these are referred to as meteor showers.

These meteors are connected with comets. Comets are essentially very large dirty snowballs travelling around the Sun. Comets leave a trail of dust behind them and if the Earth happens to pass through one of these dust trails we see a meteor shower. There are several major meteor showers during the course of the year.

The Perseids are connected with comet Swift-Tuttle, which was discovered by the American astronomers Lewis Swift and Horrace Tuttle in 1862.

This comet takes 133 years to obit the Sun. The Perseid meteor shower has a very long history.

The meteors are called Perseids because if you track their paths across the sky they all appear to come from the constellation of Perseus. It should be possible to see the Perseids after about 11pm, at first from the north east, but as the night goes on, all over the sky.

An old name for the Perseid meteors shower is the Tears of St. Lawrence. In 258 in Rome a Christian named Laurentius, sometimes referred to as Lawrence, offered the Roman Emperor Valerian all the wealth of the empire. Valerian believed that he meant gold and treasure but Laurentius meant the people of the empire. Valerian was very annoyed when he did not get the treasure he was expecting and had Laurentius killed in a most horrible way by having him roasted alive.

The execution was on August the 9th 258, and when, the following evening, the Perseids came through on schedule, people thought these meteors were tears from heaven, hence the name ‘The Tears of St. Lawrence’.

The story then goes forward to August 1535 when the French explorer Jacques Cartier was exploring the part of the then ‘new world’ that today we call Canada. While camped besides a large river he saw the Perseid meteor shower. Knowing the story of St. Lawrence and being the first European there, he named it St. Lawrence River. This great river in Canada owes its name to a French explorer and a meteor shower.

The truly dark skies return during August, which can be a spectacular month. If you are looking for the Plough you will find it to the north west of the overhead point, with Cassiopeia at about the same height in the north east.

Vega, one of the summer triangle stars, is now practically overhead and the other two stars Deneb and Altair are also very prominent. When looking at Deneb you will see the Milky Way behind it; a wonderful summer sight as it appears almost overhead at this time of the year. If you continue to follow the path of the Milky Way down towards the southern horizon you will reach the constellation of Sagittarius the Archer. Sagittarius is not seen well from Britain because it is so low in the sky; however, if you look towards it you will be looking towards the centre of our galaxy.

The rest of the southern area of the sky is difficult to navigate around because it is taken up by formless and faint constellations including Hercules, Ophiuchus and Serpens. The only bright star in this area is the red star Antares in Scorpius which is still just visible and can be found low in the south west.

If you are up and around in the early mornings during August it is possible to see the first signs of the autumn sky with the Square of Pegasus just appearing above the horizon. Pegasus will become one of our ‘anchor ‘groups in the autumn.

The Planets in August:

We finally have planets in the sky before midnight. In the south east when it gets dark we see the planets Jupiter and Saturn. Jupiter is much the brighter of the two and therefore easier to see.

Usually all the planets stay within the band of sky we call the zodiac. Just occasionally their orbit, which is the path they take across the sky, takes them out of the zodiac. This month, Jupiter is taking a trip out to visit the constellation of Cetus the Whale. Jupiter only does this about once every twelve years. I am not sure what astrologers make of this. It is worth noting that astrology now accepts that there are thirteen signs in the zodiac, the extra sign being Ophiuchus the Serpent Bearer.

Of the other naked eye planets, Mars rises just after midnight and Venus, which can be seen in the early part of the month in the morning sky, will have become too close to the Sun to be seen by the end of the month. Mercury is too close to the Sun to be seen at all this month.

Meteor Showers:

Although all the focus is on the Perseids there are several other minor meteor showers to be seen during August. These include the Aurigids which can be seen at the end of August and into early September, so it is worth while looking out for them.

Phases of the Moon for August:

First Quarter 5th, Full Moon 12th,, Last Quarter 19th, New Moon 27th

This month’s full moon is called the ‘Sturgeon Moon’. This is the month when, in past centuries, sturgeon would have been caught in the rivers of Britain. They were considered to be royal fish and the first caught had to be given to either the King or the King’s representative.

The Earby Astronomical Society is taking a summer break during July and August. The next meeting will be on Friday September 30.