June offers the stargazer a feast for the eyes under the warm summer evening skies, but this month’s highlight will be well before dark, with a rare celestial treat in the form of a partial solar eclipse.
There’s also a scorpion to discover, and a whole host of planets on view in both the evening and morning sky – plus we mark the longest day of the year.
Stars and Constellations
Featured Constellation: Scorpius The Scorpion
Scorpius the Scorpion is the Southernmost constellation of the Zodiac. Its J-shaped formation of stars presents us with one of the few constellations that actually look like its namesake. Our guide to finding our way around the scorpion is to first locate the red star Antares, which marks the heart of the creature.
May’s featured constellation was Leo the Lion, and it’s here that we will start our journey to locating the scorpion. Once we have located Leo (who is now positioned in the South West region of the sky), we must track our way across the Southern portion of the sky, heading towards the East – so scanning right to left in the evening sky. Allowing yourself the very best possible vantage point of the South, look for a bright red star fairly low down on the horizon. This will be Antares.
The Scorpius constellation contains 18 named stars. The names approved by the International Astronomical Union (IAU) are Acrab, Alniyat, Antares, Dìwö, Dschubba, Fang, Fuyue, Iklil, Jabbah, Larawag, Lesath, Paikauhale, Pipirima, Rapeto, Sargas, Sharjah, Shaula, and Xamidimura.
Scorpius is the 33rd largest constellation, but in ancient Greek times was significantly larger, because it was made up of two halves – one which incorporated the scorpion’s body and sting, and the other portion containing the claws. The latter was referred to as Chelae, meaning ‘claws’. However, in the first century BC, the Romans turned the ‘claws’ into a separate constellation, Libra the Scales.
Scorpius is one of the 12 zodiac constellations that follow a distinct path (known as the ecliptic) across the heavens. As the Earth rotates, the Sun, the Moon and planets all travel on the ecliptic, which is a sort of flat plane across our Solar System. The name ‘ecliptic’ is derived from the Greek for ‘animal circle’ – meaning Scorpius is in good company with the likes of Taurus the Bull, Cancer the Crab, and Leo the Lion.
As the world of astronomy advances, new discoveries have revealed that around 14 stars in Scorpius have been confirmed to host planets.
Scorpius in Mythology
In Greek mythology, Scorpius is associated with Orion the Hunter. Orion was a formidable hunter, who set out to kill every animal on the Earth. Meanwhile, Gaia – Goddess of the Earth and protector of the animals – was outraged by Orion’s actions, and ordered Scorpius (a huge scorpion), to kill Orion and save the animals.
Scorpius did as he was told and attacked Orion – stinging him with his stinger. To honour his bravery and show her gratitude, Gaia placed Scorpius in the night sky. As the seasons pass, Scorpius is seen chasing Orion across the sky.
During the Winter, Orion is seen to hunt peacefully and appears high up in the sky – but he dips below the horizon in the Spring and Summer months as the scorpion approaches.
Additional myths and cultural perceptions of Scorpius
- In Babylonian culture, Scorpius is referred to as zuqaqipu, which means ‘scorpion’ – and is derived from the Akkadian verb zuqapu, meaning ‘to fix upright.’
- Thousands of years before the Greeks and Romans and in a distant hemisphere, the Australian Aboriginal people also saw the stars of Scorpius as a cosmic scorpion.
- The Javanese people, who form the largest ethnic group in Indonesia, call this constellation Banyak Angrem, which translates as ‘the brooded swan.’ Or, Kalapa Doyong, meaning ‘leaning coconut tree’, due to the shape’s similarity.
Ancient Hawaiian legends state that Maui, one of the many demigods of Hawaii, once threw a magical fish hook (Manai-a-Kalani or ‘fish hook from the Heavens’) into the Pacific Ocean to pull out the other Hawaiian islands. He was trying to prove himself to his brothers who usually went fishing without him. It’s said that he pulled the hook from the islands and threw it up in the sky, where it stayed. So, to the Polynesians, the constellation of Scorpius resembles the fish hook of Maui.
The Main Stars
The three stars below mark the trail of the scorpion’s J-shape, starting with Dschubba as the forehead at the top of the constellation, Antares as the heart, and Shaula as part of the stinger.
Dschubba – δ Scorpii (Delta Scorpii)
Dscubba is 490 light-years away from Earth, and 38,000 times brighter than our Sun. Its name is taken from the Arabic, jabhat, which means ‘the forehead’. Sometimes the star is also known as Iclarcrau or Iclarkrav.
Antares – α Scorpii (Alpha Scorpii)
The brightest star in the constellation, and 16th brightest of all the stars in the night sky, is Antares. At a distance of 550 light-years away from the Sun, Antares is 75,900 times brighter and has a radius that is 850 times greater. The star’s age is thought to be around 12 million years old.
Antares marks the head of the scorpion, with its name meaning ‘rival of Ares’.
Shaula – λ Scorpii (Lambda Scorpii)
The second brightest star in Scorpius and the 25th brightest star in the sky – at a distance of 700 light-years away from Earth – is Shaula.
Shaula is made up of three stars and represents the scorpion’s stinger. The name Shaula comes from the Arabic, al-šawlā´, meaning ‘the raised (tail)’.
Other stars in Scorpius
Sargas – θ Scorpii (Theta Scorpii)
The third brightest star in Scorpius is Sargus, which sits 300 light-years away from Earth. The star is 1,834 times brighter than the Sun and 26 times larger. The name, Sargas, is of Sumerian origin – and the meaning is unknown.
Algieba – γ Leonis (Gamma Leonis)
Algieba is made up of two stars. The larger and brighter of the two stars is 320 times brighter than our Sun, while the second star is 50 times brighter. The two stars sit at a distance of 130 light-years away from Earth. A planet was discovered within the orbit of the stars in November 2009.
Acrab (Graffias) – β Scorpii (Beta Scorpii)
Acrab is composed of six stars organised into pairs of three. The stars are 400 light-years away from Earth. The name Acrab is derived from the Arabic, al-Aqrab, which translates as ‘the scorpion’.
ε Scorpii (Epsilon Scorpii)
Epsilon Scorpii is 63.7 light-years away from Earth and nearly 13 times larger than the Sun.
Girtab – κ Scorpii (Kappa Scorpii)
Girtab is made up of two stars and at a distance of 480 light-years away from Earth, is 6,911 times brighter than our Sun. The first star is 17 times larger than the Sun, with the second star also greater in size. The name Girtab is the Sumerian word for ‘scorpion’.
π Scorpii (Pi Scorpii)
Pi Scorpii, also known as ‘Fang’ comprises three stars at a distance of 590 light-years from Earth. The main star of the three is 21,900 times brighter than our Sun.
Jabbah – ν Scorpii (Nu Scorpii, 14 Scorpii)
Jabbah is made up of several stars that are 437 light-years away from Earth.
Apollyon – ι Scorpii (Iota Scorpii)
Iota Scorpii is composed of two stars. The first is 12 times larger than the Sun and 35,070 times brighter, and is officially called Apollyon. The second is is 3,700 light-years away from Earth.
Al Niyat – σ Scorpii (Sigma Scorpii)
Sigma Scorpii is made up of several stars, which sit at a distance of 568 light-years away from Earth. The star’s name Al Niyat (which the star shares with Tau Scorpii), is derived from the Arabic, an-niyāţ, which translates as ‘the arteries’. The two stars represent the arteries around the scorpion’s heart.
Al Niyat – τ Scorpii (Tau Scorpii)
Tau Scorpii is 470 light-years away from Earth and is 18,000 times brighter than the Sun.
Lesath – υ Scorpii (Upsilon Scorpii)
Lesath (which marks the Scorpion’s stinger) is 580 light-years away from Earth and is 12,300 times brighter than our Sun. The name Lesath comes from the Arabic, las’a, which means ‘pass (or bite) of a poisonous animal’.
The star lies close to the brighter star Lambda Scorpii, and the two stars form a pair sometimes known as the ‘Cat’s Eyes’.
Jabhat al Akrab – ω Scorpii (Omega Scorpii)
Jabhat al Akrab is a two-star system, and its name is derived from the Arabic, jabhat[u] al-caqrab, meaning ‘the forehead of the scorpion’ (it joins Dschubba to form part of the forehead grouping).
The first star is 424 light-years away from Earth and 9,120 times brighter than the Sun. The second is 265 light-years away from Earth.
G Scorpii is 125 light-years away from Earth. The star is 16 times larger than the Sun and 93 times brighter.
η Scorpii (Eta Scorpii)
Eta Scorpii is 18 times brighter than our Sun and is believed to be around 1.1 billion years old.
ρ Scorpii (Rho Scorpii)
Rho Scorpii consists of several stars at a distance of 409 light-years distant from Earth.
ζ Scorpii (Zeta Scorpii)
Zeta Scorpii is composed of two stars, with the first at a distance of 2,600 light-years distant from Earth. It’s one of the most luminous stars known, and is almost one million times brighter than our Sun. The second star is 151 light-years away from Earth.
μ Scorpii (Mu Scorpii)
Mu Scorpii is a two-star system. The first is 500 light-years away from Earth, whilst the second is 517 light-years away from Earth.
18 Scorpii is 45.3 light-years away from the Sun, and can be seen on the Northern border of the Scorpios constellation. In September 2003, American astrobiologist Margaret Turnbull identified the star as one of the most promising nearby candidates for hosting life, but no planets have been discovered yet orbiting the star.
Gliese 667 (142 G. Scorpii)
Gliese 667 is composed of several stars and is just 22.1 light-years away from the Sun. So far, two extrasolar planets have been found in Gliese’s orbit, and scientists believe that there could be another.
HD 159868 is 171.93 light-years away from Earth. Two planets have been discovered orbiting the star: one in 2007, and the second in 2012.
Partial eclipse of the sun
Keep your eyes peeled for a partial eclipse of the Sun on the morning of June 10th. Whilst not uncommon, where you live in the world will determine whether you get to see it.
The last partial solar eclipse visible from the UK was in March 2015. After June’s partial solar eclipse, the next is due in October 2022, then April 2024.
What is a partial solar eclipse?
A partial solar eclipse is the result of the Sun, Earth, and the Moon coming together to form an almost straight line. When this happens, the Moon’s shadow is cast over the Earth.
However, the fact the Sun, Earth, and Moon don’t align perfectly means only the outer part of the Moon’s shadow (known as the penumbra shadow) falls on Earth. The size and distance of the Moon from Earth also mean that the penumbra only covers an area of the Earth’s surface, rather than the whole thing. So, as the Earth rotates on its axis, the Moon’s shadow falls on different sections of the Earth at different times, giving the illusion of a shadow moving across our planet.
The June 2021 partial eclipse is only visible across parts of Canada, Greenland, Siberia, and the UK.
Phases of the partial solar eclipse
A partial solar eclipse has three stages. The first happens when the Moon starts moving over the Sun’s disk, and the second happens when the Moon covers more of the Sun’s disk than at any other moment during the eclipse. The final stage occurs when the Moon has begun to move out of alignment with the Sun again and is no longer covering it.
Together, these stages appear as if the Moon is slowly taking out a bitesize chunk of the Sun.
Stage 1 – 10.03 a.m.
Stage 2 – 11.11 a.m.
Stage 3 – 12.25 p.m.
Stage 1 – 10.06 a.m.
Stage 2 – 11.16 a.m.
Stage 3 – 12.30 p.m.
Stage 1 – 10.03 a.m.
Stage 2 – 11.08 a.m.
Stage 3 – 12.19 p.m.
Stage 1 – 10.08 a.m.
Stage 2 – 11.13 a.m.
Stage 3 – 12.22 p.m.
Viewing the partial solar eclipse safely
It’s important not to look directly at a partial solar eclipse using a telescope or pair of binoculars, as the Sun’s rays can cause damage to the eyes.
The safest method of viewing the eclipse is to make a pinhole camera projector, which will allow you to project an image of the eclipse onto a piece of card. You can read Nasa’s instructions on how to make your own version at home here. Aside from making a projector, the safest way to view the solar partial eclipse is to watch the event online.
In the UK, the Summer Solstice occurs on Monday June 21st at 4.32 a.m. This time and date marks the point at which the Sun reaches its most northerly point in the sky – and this is when we have the longest period of daylight and the shortest period of night.
Why does the summer solstice occur?
Our Earth makes a full rotation (spinning on its axis) once every 24 hours, which is why we have the cycle of day and night. At the same time, the Earth moves around the Sun on a 365-day journey.
However, because the Earth travels on a tilted axis, this means that during one half of the year the North side of the Earth is tilted slightly towards the Sun and the South is tilted away from the Sun – and vice versa for the other half of the year. So, the Northern hemisphere has its summer solstice at the exact moment that the Northern hemisphere is tilted most towards the Sun. This means that the number of hours of daylight has reached its maximum (while the number of hours night hours will be at their minimum).
While the Northern hemisphere is having its summer solstice, the Southern hemisphere has its winter solstice, where the daylight hours are at their shortest. Then, about six months later, the Northern hemisphere has its winter solstice, while the Southern hemisphere has its summer solstice.
June’s planets: Venus, Mars, Jupiter and Saturn
Planets in the Evening Sky
Venus will be visible in the West-Northwest portion of the sky after sunset. The planet will set about one and half hours after the Sun, and appears as a bright, unmistakable object dominating the sky – hence its nickname ‘the Evening Star’. On the evenings of Friday June 11th and Saturday June 12th, look for a crescent Moon as a guide, and Venus will be positioned nearby.
The following evening of Sunday June 13th – whilst difficult to spot – try to see if you can locate the planet Mars. To do this, start by locating the Moon. Then nearby, you will hopefully see what appears to be a reddish ‘star’, which will be Mars. On the same evening, Venus will be positioned to the lower right of Mars.
On the evening of Tuesday June 22nd, you can spot Venus to the left of Castor and Pollux in the constellation of Gemini the Twins. If you miss it, then there’s another opportunity to see Mars on Wednesday June 30th. When looking above the West-Northwest horizon, the planet will be situated to the left of Venus.
Planets in the Morning Sky
The morning sky will be dominated by Jupiter and Saturn with the pair easily visible in the South-East. Jupiter rises around three hours before the Sun and will be the brighter, more dominant of the two planets.
In the early hours of Sunday June 27th, Saturn will be positioned to the left of the Moon, and further left, you’ll locate Jupiter. The next night, Monday June 28th, the Moon lies between Jupiter to the left and Saturn to the right.
June’s Moon phases
To understand why we see phases of the Moon, we have to understand the relationship between the Earth, the Moon, and the Sun. The phases result from the changing angles of the Moon and Sun, as viewed from Earth. As the Moon orbits the Earth every month, the angle of it alters, revealing different portions of the Moon’s surface.
During the Moon’s journey around the Earth, the same side of the Moon always presents itself to us – a phenomenon known as ‘tidal locking’. The Moon is tidally locked to the Earth because it rotates in exactly the same time that it takes to orbit the Earth, which is 29.5 days, or one lunar cycle.
There are four main phases of the Moon. Together, these four phases create the outline for a lunar cycle that begins with the New Moon, then the First Quarter Moon, next the Full Moon, and then finally the Third Quarter (or Last Quarter) Moon, before the cycle starts all over again.
To be able to more clearly see and understand the Moon’s phases, it can help to make a note of the dates below; where on a clear night, you should be able to see each phase.
UK dates for June’s Moon phases:
- Third Quarter Moon: June 2nd
- New Moon: June 10th
- First Quarter Moon: June 18th
- Full Moon: June 24th
June’s ‘strawberry’ supermoon
Following on from the largest ‘supermoon’ of 2021 which occurred on Wednesday May 26th, we have the third and final supermoon of the year on the evening of Thursday June 24th.
So, what is a supermoon, and why does it occur?
Because the Earth is not directly at the centre of the Moon’s orbit (and because the Moon’s orbit is an ellipse, not a circle), the distance between the Moon and the Earth varies. When the Moon is closest to the Earth, this is known as a ‘lunar perigee’, and if this coincides with a Full or New Moon, we get what’s known as a supermoon. A supermoon appears around 7% larger and 15% brighter than an average Full Moon.
The average distance of the Moon from the Earth is 238,855 miles. April’s supermoon (which appeared pink in colour) was just 222,212 miles from Earth making it the second-closest supermoon of 2021. May’s ‘flower’ supermoon (so-called because it coincided with the blooming of flowers) was slightly closer to Earth at 222,117 miles away.
June’s supermoon is the most distant of the three supermoons at 224,662 miles away. It’s referred to as the ‘strawberry’ supermoon because of the ripening of the fruit at this time of year.
June’s sunrise/sunset times
Start of June: Sun rises at 4.54 am. Sets at 9.49 p.m.
End of June: Sun rises at 4.51 am. Sets at 10.02 pm
Start of June: Sun rises at 4.39 am. Sets at 9.50 p.m.
End of June: Sun rises at 4.59 am. Sets at 9.33 pm
Start of June: Sun rises at 5.01 am. Sets at 9.20 pm
End of June: Sun rises at 5.02 am. Sets at 9.19 pm
Start of June: Sun rises at 4.48 am. Sets at 9.08 pm
End of June: Sun rises at 4.47 am. Sets at 9.21 pm
If you’re new to stargazing or astronomy, and you’d like a general introduction to the night sky, then you might want to check out our beginner’s guide here.
Jonathan is a contributor to the BBC Sky at Night magazine. He has written three books on astronomy, Cosmic Debris; Rare Astronomical Sights and Sounds (which was selected by ‘Choice’ magazine as an Outstanding Academic Title for 2019); and From Cave Art to Hubble, all of which are available from Amazon. Jonathan worked at BBC Radio Wales as their astronomy correspondent and is currently a columnist at the South Wales Argus. He has also written a book on castles, ‘Fortress Wales’, and was part of the writing team for the BBC Television show, ‘The Fast Show’, which won a BAFTA.