Eyes on the Night Sky – March 2021
March heralds the start of not one, but two ‘springs’! Meteorological spring on the 1st of the month and astronomical spring starts on 20th March. The difference between the two is that the astronomical spring (or Spring/Vernal Equinox) is related to the position of the Earth’s orbit in relation to the Sun and marks the moment the Sun crosses the imaginary celestial equator in the sky that is directly above the earth’s equivalent and lies 90 degrees from the Earth’s poles. Meteorological Spring is based on the Gregorian calendar and the annual cycle of temperatures.
This month is good news for fans of the ethereal Zodiacal Light. March is a great time to see it. Ideally, a rural area is best for viewing it around 80-120 minutes after sunset. The Moon’s light will disrupt viewing so try and find the Zodiacal Light during moonless dusks. This phenomenon continues in the first two weeks of April, so there is plenty of time to experience this natural wonder!
The photograph taken at Cerro Paranal, Atacama Desert, shows a very strong cone of light , due to lack of light pollution. The Zodiacal Light isn’t as strong in the UK, but is defintely visible to the unaided, dark adapted eye. (Credit: ESO/Y. Beletsky)
The new Moon occurs on 13th March and the full Moon on 28th March.
Spot with the Unaided Eyes: Conjunction of Mars and Pleiades Star Cluster
On 3rd March, look towards the western sky to see Mars and the Pleiades Star Cluster – also known as the Seven Sisters pass each other at 2.7 degrees distance. Hold out your arm with your finger extended – that’s about how close these two objects will be. It’s a rare event – the last time this occurred was thirty years ago. Mars and the Pleiades Star Cluster will not pass close to each other again until 2038.
Spot with Binoculars: A Nearby Beehive Cluster
We cannot go into the spring without acknowledging this lovely star cluster, which resembles a swarm of bees! This object has three designations assigned to it: M44, named after 18th Century astronomer and comet finder Charles Messier, who added it to his catalogue as one to avoid as it wasn’t a comet. Praesepe is a more ancient name; it means eat, manger or crib in Latin. It was thought that the manger was the feeding trough for the stars Asellus Borealis and Asellus Australis (Northern and Southern Donkeys) who, according to Greek and Roman myth, were led into battle to fight against the Titans and later became the symbolic manger of Jesus Christ.
With such myth and legend associated with such an object, this open star cluster is not very bright in today’s light polluted skies but comes alive through binoculars with small, pinpoint stars swarming in the field of view which gave this grouping of pretty stars its current name: the Beehive Cluster. There are a thousand stars in this open cluster and is situated around 610 light years from the Solar System. It is one of the nearest open clusters to our Sun.
Spot with a Telescope: A Faraway Galaxy
As we move into ‘galaxy season’, one object to look at is an isolated barred spiral galaxy in the constellation of Leo named NGC 2903. You will need a telescope of around 6 inches aperture and larger to see it. Positioned 1.5 degrees south of Lambda Leonis, it lies 30 million light years away from our Milky Way and has a close resemblance to it. Galaxies like these are interesting to study the processes that precede star formation.
This stunning Hubble image (Credit: HST)) shows the orange line of light running through the galaxy which is its bar – it is thought that this region provides material to form new stars. To discover it, look for the head star of the constellation of Leo called Algenubi and find a fainter neighbouring star called Lambda Leonis. Train your finder scope on Lambda Leonis through your eyepiece, slowly scan the area directly below until a faint ‘fuzzy’ object appears in your eyepiece. Through a small telescope, you will see a faint, well-formed ellipse and through larger telescopes, you may be able to discern a bright core. Try using averted vision to see the galaxy more clearly.