The Sky Above You – April 2021

By Duncan Lunan

The Moon will be New on April 12th, and it will be Full on April 27th.  Though not a ‘supermoon’, when the Moon is Full at its nearest to Earth, the April Moon comes between two of them and will not be much inferior to either.  We’re awaiting results from the Chang’e 5 spacecraft, with which China returned samples from the Moon in December last.  The landing site in northern Oceanus Procellarum is estimated to be ‘only’ 1.2 billion years old, 2 billion years younger than the ones visited by Apollo astronauts and Soviet sample-return probes 45 years ago, so we should learn a lot more about the history of the Moon.

The planet Mercury comes back to the evening sky after superior conjunction with the Sun on the 19th.  Mercury is very close to the right of Venus on the 25th, and above it, between the Moon and the Pleiades, by the end of the month.

Venus too returns to the evening sky mid-month, setting at 9.15 p.m. by the end of April.   Mercury and then Venus are passed by the Moon on April 11th-12th, too near New Moon to see. 

Mars moves from Taurus into Gemini, growing ever fainter as the Earth pulls ahead of it, setting now at 1.30 a.m..  The Moon is close to Mars on the 17th, seen from here, and will pass behind the Moon in daylight, as seen from India and southeast Asia.

Jupiter and Saturn are both in Capricornus, rising at 4.30 a.m., with the waning Moon near them on the 6th and 7th.   The Juno spacecraft orbiting over the poles of Jupiter was originally to have ended its mission in July 2018, but because its orbit couldn’t be lowered as intended, the mission was to be extended to July 2021 and has now been extended to July 2025 at least.   Excitingly, precession of the orbital plane meantime will now allow multiple close flybys of the major moons Io, Europa and Ganymede, which will come within range of the spacecraft’s advanced instruments for the first time.

Uranus in Aries sets around 9 p.m. in March, near the Moon on the 13th, and by the 30th it’s at conjunction on the far side of the Sun.

Neptune reappears in the morning sky, rising in Aquarius around 4.30 a.m., with the Moon nearby on the 9th.

You can download a copy of the star map for April 2021 here:

The Lyrid meteor shower from Comet Thatcher peaks on the night of the 21st/22nd, but will be spoiled by moonlight this year..My space travel stories, old and new, have been collected and published by Other Side Books as From the Moon to the Stars, relating to the Moon and Project Apollo, and The Other Side of the Interface, with a wider scope.   Both have illustrations by Sydney Jordan, and are available through Amazon or through bookshops.  Details of them and my other books are on my website,

If you are a beginner to astronomy Duncan Lunan has an excellent series Astronomy Beginner’s Guide: Part 2 Compass Points in the Sky

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