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I have just seen this article and thought it an interesting read, so I thought it was worth a share, you never know we may get a few clear night skys to observe the wonderful stars and planets in our heavens

When the Moon, planets and stars come together to form a conjunction, the results can be spectacular. Find out which conjunctions to look for in the night sky.

Conjunction: what a funny-sounding word it is, yet in the field of astronomy this phenomenon can give us some wondrous night-sky sights, ranging from naked-eye views through to binoculars and even using a telescope.

There are usually a few beautiful conjunctions to see in the night sky if the weather permits – or early morning sky for that matter – each month, and below we’ll look at some of the best coming up over the next few weeks

What is a conjunction in astronomy?

Generally speaking a ‘conjunction’ is the name given to two or more celestial objects close together in the night sky.

The most commonly observed conjunctions involve the Moon, often as a crescent in the evening or morning sky, along with any of the bright planets Venus, Mercury, Mars, Jupiter or  Saturn

You can also see conjunctions between the Moon and brighter stars or even between the planets themselves, so there is quite a range of possible combinations.

Some involve more than two objects, such as when two planets are in conjunction and are joined by the Moon.

There are also times when incredibly close conjunctions set two objects in the same telescope field of view, or in really special cases, show Venus or Mercury transit across the face of the Sun.

You may already have come across the term in astronomy guides, yet if we went by its strictest definition then some events called conjunctions would probably not qualify.

To be precise: a conjunction is a line-up of at least two celestial objects in the sky relatively close together that share the same Right Ascension (RA) or ecliptic longitude in the sky.

• RAis the equivalent of longitude on Earth but projected onto the celestial sphere
• The eclipticis the plane of Earth’s orbit and appears to us as the apparent path of the Sun across the sky. Ecliptic longitude is measured along the ecliptic eastwards from the spring equinox

Even within astronomy there are different meanings of the word conjunction.

• When a planet, either outer or inner, lies on the other side of the Sun to Earth it is said to be at superior conjunction
• When an inner planet lies between Earth and the Sun it is at inferior conjunction

When do conjunctions occur?

Often a conjunction will occur during daytime or when the objects are below the horizon, and this is where the definition becomes more relaxed.

If the objects are very bright, such as a crescent Moon and Venus, then daylight viewing can be possible, but if the objects have set below the horizon they won’t be visible.

So conjunction can be applied in quite a loose context to refer to objects that are viewable above the horizon in twilight or at night, even if they are not, at that point, at the exact moment of conjunction.

• If the objects are at their closest, then this is known as an appulse: the minimum separation between two bodies that occurs just before or after true conjunction.

Conjunctions really capture our attention, which makes them ideal targets for public stargazing events, or for inspiring young astronomers and newcomers to look up at the night sky.

They are also easy to capture with a smartphone camera, giving more people the chance to preserve the moment and share with friends or on social media.

Upcoming conjunctions to see in the night sky

Below we’ll look at some fascinating conjunctions coming up over the next few weeks between the Moon, planets and stars.

3 November: Mercury and the Moon

During mid to late October Mercury returned to the morning twilight, best morning apparition lasting into November. The innermost planet is always brighter at the end of the apparition, so November is a good time to catch it if you are an early riser.

Mercury was at greatest elongation west from the Sun on 25 October when it lay 18 degrees from it and from 1 November it should be viewable until mid-month as it descends back into the solar glare.

On 3 November the slim Cresent Moon lies above Mercury, adding to the view, and keen-eyed observers may also spot Spica as it emerges from the solar glare.

7, 8 November: Venus and the Moon

Venus is still with us, lingering all month low in the southwest evening twilight sky. However, it gradually improves in height as the month wears on and this is down to the eliptical gradually becoming steeper as it intersects the horizon with each passing day. Venus is also catching up with Saturn and Jupiter.

The evening crescent Moon lies either side of Venus on 7 and 8 November, which makes for a a good guide to help you find the planet.

10, 11 November: Mercury and Mars

You may also get a chance to spot Mars near to Mercury on 10 and 11 November very low down towards the east-southeast morning twilight horizon.

More conjunctions in November 2021

• 2 November: Crescent Moon forms triangle with Zaniah and Porrima in Virgo (morning)
• 12 November: Northern Taurids Meteor shower peak (morning, favourable)
• 13 November: Moon forms triangle with Neptune and Psi Aquarii (evening)
• 17 November: Moon lies between Uranus and Xi Ceti (evening)
• 19 November: (Very) Partial Lunar Eclipse just as moon sets (morning)
• 22 November: Moon lies near to Mebsuta Epsilon Geminorum (evening)
• 23 November: Moon forms triangle with Castor and Pollux (evening)
• 24 November: Moon lies above Beehive cluster (late evening)
• 26 November: Moon lies close to Eta Leonis and north of Regulus (late evening)
• 27 November: Last Quarter Moon lies to upper left of Regulus (morning)
• 30 November: Crescent Moon lies near to Porrima (morning)

 

(credit Sky At Night Magazine)