Photo: EUROPEAN SPACE AGENCY

The May 2021 Night Sky

Welcome to the May night sky. This is the time of the year of sunny days and dark clear nights, at least in southern Europe. The three most easily visible planets in the early evening sky are now Mars, Venus, and Mercury.

Looking towards the west shortly after sunset on warm May evenings, we have the red planet Mars in the constellation of Gemini. This planet will be seen at an altitude of 30 degrees approximately, shortly after darkness falls. At the same time, and much lower down on the west north-western horizon, the bright planet Venus can be seen moving away from the glare of the Sun to become an evening star.

Now, the elusive planet Mercury is also moving away from the Sun and, on the 17th, it is at its greatest western elongation from the Sun and, therefore, at its most visible this month.

The planet Mercury is not much larger than our own Moon and never far from the Sun, but now we have the best chance of seeing it without a telescope.

Venus is much more brilliant than Mercury and, on the evening of 29th, the pair are close together low in the west northwest. Venus will be mainly white in colour whilst Mercury will appear as a faint pinkish star-like object. This is the best time to spot the elusive Mercury without a telescope.

On May 12, the thin crescent Moon will be seen close to Venus and, from some parts of the world, it will pass in front of the planet from our point of view.

Unfortunately, this event will not be seen from Europe.

For northern hemisphere observers, the easily recognisable constellation of Ursa Major, the Great Bear, is to be seen overhead during late spring evenings and the Zodiacal constellation of Virgo is to be seen crossing the southern Meridian.

Our view of the night sky this time of the year is at right angles to the plane of the Milky Way Galaxy, and this allows us to see beyond the dust and gas of its spiral arms and out into the depths of the Universe. In this direction, we have a view of billions of remote galaxies rendered barely visible due to their immense distance from us. With a small telescope or strong binoculars, hundreds of these fascinating objects are visible, if you know exactly where to look.

Elon Musk’s SpaceX company has just been awarded a contract worth nearly three billion dollars to take NASA astronauts back to the Moon to start setting up a permanent colony, possibly within the next five years.

The Moon is last quarter on the 3rd, new on the 11th, first quarter on the 19th and full on May 26.

By Clive Jackson
|| features@algarveresident.com
Clive Jackson is the director of the Camera Obscura attraction (next to the Castle in Tavira), specialising in education and public outreach.
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To see the May Sky Map click on the pdf link below

2021-05 May nightsky