Looking to the Skies March 2024 By Brian Davidson

We have had a tremendous amount of rain recently so I hope you have made the most of the clear evenings that we have had.
 
Observing

The following chart represents the night sky at 10.00pm GMT on the 8th of March and at 9.00pm GMT on the 23rd March. To use the chart, face your southern horizon at the appropriate time and you will see the stars in the chart.

                                                                                                       Courtesy In the Sky.org Edited by Brian Davidson
 
You should not have any difficulty in locating our two major constellations this month as they stand out in their own right. The night sky has rotated another two hours westwards compared to the same time in the evening as last month so the two Gemini stars, Castor and Pollux, are on the right hand side of the chart this month. If in doubt, look a little further to your right and you will see Orion.
The constellation Ursa Major- The Great Bear, is better known through its asterism, The Plough, outlined in red on the chart. Facing south it will be awkward to observe as it will be beyond your zenith but if you follow a line from the pointer stars, Dubhe and Merak, down to your southern horizon you will quickly recognise the zodiacal constellation Leo- The Lion. At least it looks a bit like a crouching lion and it too has a well known asterism, The Sickle, outlined in red. It looks like a backward question mark and the top half represents the lion’s head. The brightest star in Leo is Regulus, located at the bottom of the sickle or the dot at the bottom of the question mark. Regulus is a large blue-white star at a distance of eighty light years from Earth and with a magnitude of 1.4 it is one of the brighter stars in the northern hemisphere. The other two named stars in Leo, Algieba and Denebola, are not so well known but with magnitudes of 2.1 and 2.2 they help to make Leo stand out in the evening sky.
Two further constellations to mention in passing but neither have any bright stars and they are both late additions to the list of classical constellations. Leo Minor- The Little Lion, lies just above Leo but bears no obvious resemblance to a lion. The constellation Lynx-The Lynx, is relatively large and lies between The Plough and Gemini but with its brightest star at magnitude 3.2 clear sky conditions are needed to see just the one star.
We will return to Ursa Major now, so retrace the line from Leo above your zenith and turn round and face north for easier viewing. We all know The Plough, but the constellation Ursa Major is the third largest constellation in the night sky and its fainter stars cover a wide area. Having turned round you will find that The Plough is now upside down. It consists of seven stars and just for completeness they are all named on the chart. Apart from Megrez, their magnitudes range from 1.8 to 2.4 and that is why The Plough is so prominent. The constellation Ursa Major is circumpolar which means that during a year it rotates about the north celestial pole where Polaris the north pole star is located. Remember that a line from the pointer stars, Merak and Dubhe, takes you to Polaris and a line from Alioth through Polaris takes you to another circumpolar constellation, Cassiopeia, which was high in the sky last Autumn but is now close to the horizon having exchanged places with the Plough. As a point of interest, Mizar, the second star along The Plough’s handle is an optical double and has been used as a test for how good your eyesight is.
Remember to enjoy the sight of Orion while it is there because we lose it by summertime.
 
Something to look out for
There is another close approach of the Moon and Jupiter on Wednesday 13th March from 6.30pm until setting at 11.00pm. A chance to say goodbye to Jupiter.
            Mercury is often a tricky planet to catch close to sunset but by Thursday 14th March it sets 90 minutes after the Sun shining at magnitude-1.0. By Saturday 23rd March, Mercury will be at dichotomy (half phase), setting two hours after the Sun and still with a magnitude of -0.5. Surely there will be sufficient clear skies to catch it at some point over that time period!
            The March equinox is on Wednesday 20th March and we change from GMT to BST at the end of the month so remember to put your clocks forward by one hour.
Clear skies.