Your guide to the night sky this month

All Month

Noctilucent cloud season begins from late May through to early August, making June an excellent month to look out for these high-altitude marvels.

Comet C/2017 K2 PanSTARRS continues to brighten and is well placed in northeast Ophiuchus.

Wednesday 1

Mag. –2.1 Jupiter appears 1.6˚ from mag. +0.7 Mars in the morning sky. Spot them low above the eastern horizon after 03:30 BST (02:30 UT).

Thursday 2

This is the first and best window of opportunity to look for our ‘Deep-Sky Tour’ targets in Ophiuchus. The second window occurs in the last week of June, when nights are at their shortest for the year. 

Friday 3

This evening the ‘Star of the Month’, Kornephoros (Beta (β Herculis), reaches its highest altitude, due south around 01:00 BST (midnight UT).

Monday 6

Minor planet 29 Amphitrite reaches opposition. Shining at mag. +9.7, Amphitrite can be found low in Scorpius, the Scorpion in June. 

This evening’s almost first quarter Moon will reveal the clair-obscur effects known as the Lunar X and V.

Thursday 9

The first of two opportunities this month to catch our ‘Moonwatch’ target, the crater Hortensius, occurs this evening. Hortensius lies near an impressive series of six domes known as the Hortensius Omega dome field.

Friday 10

Mag. +4.4 Theta (θ) Virgin is is occulted by this morning’s 74%-lit waxing gibbous Moon from 01:50 BST (00:50 UT) – times correct for the centre of the UK – ending just before both objects set.

Tuesday 14

The full Moon at 12:52 BST (11:52 UT) occurs almost 12 hours before lunar perigee, when the Moon is closest to Earth in its orbit. Look out for this so-called ‘supermoon’ this morning to witness the Moon illusion.

Thursday 16

Mercury reaches greatest western elongation today, the planet appearing 23.2° west of the Sun in the morning sky.

Sunday 19

This morning’s 72%-lit waning gibbous Moon lies 8° east-southeast of mag. +0.7 Saturn. Catch them both above the southeast horizon around 02:00 BST (01:00 UT). 

Tuesday 21

At 10:14 BST (09:14 UT) the Sun reaches its most northerly position in the sky, a point in time called the Northern Hemisphere’s summer or June solstice.

Wednesday 22

The 40%-lit waning crescent Moon lies 6.3° to the east of mag. –2.2 Jupiter in the morning sky. 

Thursday 23

This morning’s 30%-lit waning crescent Moon sits 3.8° east of mag. +0.5 Mars. 

Sunday 26

There’s a gorgeous view of mag. –3.8 Venus near a 7%-lit waning crescent Moon above the northeast horizon this morning from 03:00 BST (02:00 UT), mag. –0.2 Mercury following about 40 minutes later. The Moon lies 1.9° from Venus at 06:20 BST (05:20 UT).

Monday 27

Mag. –0.3 Mercury lies 3.3° from the centre of a slender 3%-lit waning crescent Moon this morning. Catch the pair low above the northeast horizon around 04:00 BST (03:00 UT). 

Thursday 30

Clear skies at the end of June gives those with a low southern horizon a view of the Teapot asterism at the heart of Sagittarius. Binoculars pointed north of the spout will reveal wonderful deep-sky objects such as the Lagoon Nebula, M8, and the Trifid Nebula, M20.

Family stargazing

The full Moon on 14 June, and fuller phases on following nights, appear huge when close to the horizon around moonrise due to the ‘Moon illusion’. The Moon is in the correct position for this at 23:00 BST (22:00 UT) on the 14th. If clear, ask young observers to view it and then turn their back on it. Ask them to estimate how large it was using their thumb and forefinger at arm’s length. Then turn them around to look at the Moon and get them to measure its real apparent diameter using a thumb and forefinger at arm’s length. Chances are the first estimate is too big! bbc.co.uk/cbeebies/shows/stargazing

NEED TO KNOW

The terms and symbols used in The Sky Guide

Universal Time (UT) and British Summer Time (BST)
Universal Time (UT) is the standard time used by astronomers around the world. British Summer Time (BST) is one hour ahead of UT

RA (Right ascension) and dec. (declination)
These coordinates are the night sky’s equivalent of longitude and latitude, describing where an object is on the celestial ‘globe’

Naked eye
Allow 20 minutes for your eyes to become dark-adapted

Photo opp
Use a CCD, planetary camera or standard DSLR

Binoculars
10×50 recommended

Small/ medium scope
Reflector/SCT under 6 inches, refractor under 4 inches

Large scope
Reflector/SCT over 6 inches, refractor over 4 inches

GETTING STARTED IN ASTRONOMY

If you’re new to astronomy, you’ll find two essential reads on our website. Visit http://bit.ly/10_easylessons for our 10-step guide to getting started and http://bit.ly/buy_scope for advice on choosing a scope