his May is a month for early risers.
In the early morning — 4.30am! — on Tuesday May 12th those with a good SSE horizon will see a conjunction of Jupiter and the Moon at an elevation of just 16°.
The Moon will be 2.25 degrees south of the giant planet — that's a separation of just over four Moon diameters. Conjunctions are juxtapositions of the Moon and planets as they move through the heavens
on their monthly and yearly cycles. They have no particular meaning for astronomers but they can be spectacular sights. Perhaps some of you saw the waxing crescent Moon and Venus close together just
after sunset in the western sky on April 26th?
By the way — if you have not yet spotted Venus in the western sky after sunset yet don't miss it — June will be too late!
If you are up early you might see meteors from the Eta Aquarid shower that peaks this month. We expect a maximum rate of about a dozen meteors in the two
hours before dawn (that's 2.45am to 4.45am) on 5th and 6th May (although these rates are notoriously hard to predict).
Unfortunately this will not be a particularly good occasion to see the Aquarids as the Moon is close to full.
The name Aquarids refers to direction in the sky from which the meteors appear — in the constellation of Aquarius.
The meteors themselves are small fragments of debris from the tail of comet Halley that the Earth passes through twice per year
in May & in October when we see the Orionids.
On June 4th Mercury (a tough planet to spot) will be at its greatest angular separation from the Sun (23.6°) and so you'll have your best chance
to see it in the western sky just after sunset. From these latitudes the few days around the end of May (26th May - 4th June)
are the best time to view Mercury since it will be at its highest point above the horizon - 16° - in the evening sky at sunset (~9.00pm).
Help with locating these events can be found using the interactive sky map at: https://in-the-sky.org/skymap2.php
Something we will not see this month is Comet Atlas. Discovered on December 28th 2019 it reaches its closest approach to Earth on May 23rd when it will be 72 million miles (116 million kilometres) from Earth.
Excitement that this Sun grazing comet might be a spectacular naked eye object was dampened when it started to break up in April as it approached the Sun. It will not be visible to the naked eye.
I can't close this month's diary without mentioning the 30th anniversary of the launch of the Hubble Space Telescope which lifted off from the Kennedy Space Centre in Florida on 24th April 1990.
To celebrate, NASA have released a new picture [NASA Original
displayed in part at the head of this article] of two nebulae in the Large Magellanic Cloud — a satellite of the Milky Way 163,000 light years away.
The red nebula is the result of the birth of a cluster of stars 10-20 times as massive as the Sun.
The blue nebula is the result of the birth of single star more than 20 times as massive as the Sun that has blown off its outer envelope.
We learn much about how stars form from these images but equally they illustrate what a spectacularly beautiful place the Universe is.