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Welcome to this month’s edition of Eyes on the Night Sky, where we will select the best highlights of the month for the unaided eyes, binoculars and telescopes. There is no requirement to own optical equipment to get started in stargazing as there is plenty to gaze at using the eyes alone, especially this month, as there are some spectacular, celestial treats to look out for. Grab a flask of your favourite hot drink, put on some warm clothing and get outside!

Zodiacal Light

Zodiacal Light

©Sam Price

If you have access to dark skies, away from the light pollution of towns and cities, you can look out for the Zodiacal Light, which emerges into the western sky about an hour after sunset. With dark adapted eyes, look out for a cone of light shining at an angle from the horizon upwards. It may look like a strong, artificial light is being shone upwards. This is a natural phenomenon caused by debris from comets and dust from asteroid collisions in our Solar System that can be seen during late February, and throughout the months of March and April. You will need a moonless dusk to see it; ideal opportunities are between 10th and 25th March. The image above was taken in the Elan Valley International Dark Sky Park.

The Full Moon is on 9th March and the New Moon is on 24th March.

Comet Challenge
Sky map of the position of Comet C/2017 T2 (PANSTARRS).

Here’s a challenge for binoculars – try and find a comet! Comet C/2017 T2 (PANSTARRS) is currently well placed in the constellation of Cassiopeia and is just within the reach of 10x50 binoculars. Find a moonless, dark sky, away from light pollution and find the ‘W’ shaped constellation of Cassiopeia, which by 9pm, will be on its side. Find the top two stars of the constellation and place the binoculars to your eyes, scanning upwards slowly, until you see a faint, white smudge. 

Over the month, the comet will be moving towards the constellation of Camelopardalis, so try to keep track on the comet as it travels Sunwards, or reaches Perihelion, on 4th May. It is not known whether the comet will brighten further or not, as it largely depends on its behaviour as it is battered by the Sun’s heat. Keep an eye on this comet’s progress as it could potentially reach unaided eye visibility in May – but we will not know until at least a week or so before.

A Conjunction Bonanza

Planetwise, Venus continues to be well placed in the western sky and it lovely to see emerge into the dusk sky as one of the first ‘stars’ of the evening . It will reach greatest elongation on 23rd March - read more about what this means.

For the unaided eye, there is a fabulous planetary conjunction bonanza occurring towards the end of the month.

On 18th March, three planets and the Moon will share a conjunction – look in the south eastern sky at around 4.30am to see Mars only 1°24' away from Jupiter, the Moon around 1.5° west  and Saturn, 7° lying west of this spectacle. Mercury rises from the SSE at around 5.30am; an opportunity to see four planets in one go!

Conjunction of Saturn, Mars and Jupiter.

On 20th March, Jupiter rises a couple of hours before sunrise throughout the month; Mars and Saturn rises alongside. An amazing triple conjunction will occur on 20th March, with Jupiter passing a staggeringly close 0°42' to the north of Mars (from our perspective). In addition, Saturn will be around 7° east of the two planets.  

You can enjoy the close dance of Mars, Jupiter and Saturn at around the same time each morning for the rest of the month. Try studying the planets and its moons with binoculars, ideally fixed to a sturdy tripod or a telescope, if you have one. 

The Eyes Have It

NGC4438 and NGC4435, better known as 'The Eyes'.

NGC 4438 and NGC 4435 taken by FORS2 instrument of the Very Large Telescope (Credit: ESO)

If you have a telescope that has an aperture of six inches and above, visit a dark sky and try to look for a pair of interacting galaxies in the constellation of Virgo called ‘The Eyes’ – named as such, for they resemble a pair of glowing eyes from the depths of space. Also known as NGC 4435 and NGC 4438  or Arp 120, they lie 52 million light years from Earth. Currently 100,000 light years apart, they once got as close as 16,000 light years apart, which was close enough to cause a ‘collision’, where stars, gas and dust were ripped away – NGC4435’s distorted disk and tidal tails bear witness to the collision.

Imagine a line running between the star Vindemiatrix in Virgo and Denebola in Leo; the galaxies are almost placed in the centre of the two stars. They are part of a lovely galaxy string known as Markarian's Chain, which we will explore next month.