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What’s In June’s Night Skies


Mercury will start the June in the early evening in the Gemini (The Twins) Constellation where it will set at 06:49 pm (AWST). Mercury will have its greatest elongation in the West on the 4th of June, where it’ll begin to make its way back towards the Sun from that day and be lost to the Sun’s glare by the start of the final week of June. Venus, Earth’s twisted sister reappears in the morning sky towards the end of the second full week of June. On Friday the 12th of June it’ll rise at 06:11 am (AWST) and by the end of the month Venus will rise at 04:41 am (AWST).

Mars will start the month of June in the Aquarius (The Water Bearer) Constellation as an orange dot and will move into the Cetus (The Sea Dragon) Constellation in the last week of the month. The planet will rise at 00:09 am (AWST) at the beginning of the month and by the end of the month, it’ll rise at 11:41 pm (AWST). Jupiter, the king of the planets can be still be found in the Sagittarius (The Centaur with a Bow) Constellation this month. At the beginning of the month, it’ll rise at 08:30 pm (AWST) and by the end of June, it’ll rise at 06:23 pm (AWST). Saturn will start of June in the Capricornus (The Sea Goat) Constellation and then move during the month move in between the Capricornus (The Sea Goat) and Sagittarius (The Centaur with a Bow) Constellations. it’ll rise at the beginning of the month at 08:53 pm (AWST) and by the end of the month it’ll rise at 06:52 pm (AWST).

Uranus continues to be in the Cetus (The Sea Dragon) Constellation and it’ll rise at 05:59 am (AWST) at the beginning of June. By the end of the month it’ll have started to move into the Aries (The Ram) Constellation and will rise at 02:46 am (AWST). Neptune, the last planet in our Solar System can be found in the early morning sky between the Aquarius (The Water Bearer) and Pisces (The Fish) Constellations for the whole of June. The planet will rise at 00:50 am (AWST) at the beginning of the month and by the end of the month at 10:53 pm (AWST).

Mercury on the 15/06/20 at 06:00 pm. Image Credit: Stellarium Mercury's greatest elongation in the West on the evening of 04/06/2020. Image Credit: Stellarium
Venus and Uranus on the 15/06/20 at 06:00 am. Image Credit: Stellarium Mercury near its greatest elongation in the West on the evening of 23/06/20. Image Credit: Stellarium

Conjunctions and Occultation

Conjunctions involve object(s) in the Solar System and/or more distant objects, such as a star. It’s an apparent phenomenon in which multiple objects which aren’t close together appear close in the sky and it’s caused by the observer’s perspective. An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer.

  • 02/06/20 – Conjunction of the Moon and Spica (Where to look)
  • 05/06/20 – Conjunction of the Moon and Antares (Where to look)
  • 08/06/20 – Conjunction of the Moon, Jupiter and Saturn (Where to look)
  • 09/06/20 – Alignment of the Moon, Jupiter and Saturn (Where to look)
  • 13/06/20 – Conjunction of the Moon and Mars (Where to look)
  • 19/06/20 – Alignment of the Moon, Venus and Aldebaran (Where to look)
  • 25/06/20 – Conjunction of the Moon and Regulus (Where to look)
  • 29/06/20 – Conjunction of the Moon and Spica (Where to look)

Astronomical Events This Month

Penumbral Lunar Eclipse:

On Saturday the 6th of June, a Penumbral Lunar Eclipse will occur where the Sun, Earth, and the Moon are imperfectly aligned, and the Moon passes within Earth’s outer shadow (Called the Penumbra). Most Penumbral Lunar Eclipse cannot be easily distinguished from a usual Full Moon as at the maximum phase of the eclipse you’ll see the Moon turn a shade darker.

This is the second of four Penumbral Lunar Eclipse for 2020, and Perth will see it. The best place to see this eclipse is in Africa, the Middle East, Central and South East Asia, the Subcontinent and Australia. The eclipse starts in Perth at 01:46 am (AWST), with the maximum phase occurring at 03:25 am (AWST) and the eclipse finishing at 05:04 am.

The Moon's Location at the time of maximum phase. Image Copyright: Stellarium Total Lunar Eclipse viewing map. Image Credit: Total Lunar Eclipse diagram. Image Credit: Bob King and Starry Night
The June Solstice:

The June Solstice occurs on the 21st of June at 05:44 am (AWST), marking the beginning of astronomical winter for the southern hemisphere, and the start of summer for the northern hemisphere. This is an exact moment when the Sun’s declination equals 23.5 degrees south as seen from the Earth. The line of latitude where the Sun passes directly overhead during the June solstice is known as the Tropic of Cancer, although in modern times, the Sun is in the astronomical constellation of Gemini in mid-June. Thanks to precession.

The June solstice means the southern rotational pole of the Earth is tipped away from the Sun and will now begin its long apparent journey northward again until December. The wobble of Earth’s axis known as the Precession of the Equinoxes takes about 26,000 years to complete one ‘wobble.’ Live out an average 72-year life span, and the equinoctial points will have moved one degree (about twice the diameter of a Full Moon).

The Earth's position around the Sun at Solstices and Equinoxes. Image credit: The June Solstice. Image Credit:
Annular Solar Eclipse:

On Sunday the 21st of June, the Moon passes between the Earth and Sun and will almost completely eclipse the Sun for a small region on the Earth between 11:46 am (AWST) and 05:34 pm (AWST). This is called an Annular Solar Eclipse and what happens is the Moon covers the Sun’s center, leaving the Sun’s visible outer edges to form a “ring of fire” or annulus around the Moon.

Unfortunately, Perth we’ll miss out on this Annular Solar Eclipse as the path will start in Gabon, Africa and then it will move north east through the Arabia Peninsula and up to the top of India before moving through China and then finishing over the Pacific Ocean. It won’t be all bad for us in Australia, if you’re going to be in the top of the Northern Territory and the Cape of York, you’ll be able to see some form of Partial Solar Eclipse.

Watch it online with Slooh:

WARNING: Please for the love of God don’t look directly at the Sun even during an Eclipse, You WILL lose your eyesight.

An Annular Solar Eclipse. Image Credit: June's Annular Solar Eclipse viewing map. Image Credit: Types of Solar Eclipses. Image Credit:

Things to Look at This Month

Centaurus A:

Centaurus A or NGC 5128 is an elliptical galaxy that we see edge-on. The galaxy is the fifth brightest galaxy in the sky and one of the closest radio galaxies to earth. It’s between 10 to 16 million light years away from us and It can be found in the Centaurus constellation. The galaxy itself has a diameter of 60,000 light years making it 40% smaller than our galaxy and at its centre it has a supermassive black hole with a mass of ~55 million suns. It was discovered in 1826 by Scottish astronomer James Dunlop from Parramatta, in New South Wales.

It’s a starburst galaxy meaning that it is undergoing a period of intense star formation compared to an average galaxy. Studies have confirmed that this high rate of star birth is caused by a collision between itself and a smaller spiral galaxy. The bright central bulge and the dark dust lane can be easily viewed using an amateur telescope however a larger telescope is required to view greater detail and contrast. Centaurus A is an extremely bright radio object, X-Rays in particular. The central supermassive black hole is the source of this with two long radio jets extending well beyond the visual bounds of the galaxy.

Centaurus A on the 15/06/20 at 09:00 pm. Image Credit: Stellarium The Centaurus A Galaxy - Image Credit: ESO/WFI (Optical); MPIfR/ESO/APEX/A.Weiss et al. (Submillimetre); NASA/CXC/CfA/R.Kraft et al. (X-ray)
Ptolemy Cluster:

The Ptolemy’s Cluster (M7 & NGC 6475) is a large open cluster near the sting of the tail of the constellation of Scorpius. While it’s 980 light years away from us, it’s large enough to be seen with the unaided eye in a dark sky and is a nice sight in binoculars. The cluster is 25 light-years across, and it contains around 100 stars in total. It was first described by the Greek-Roman astronomer Ptolemy in 130 AD from which it gets its common name of Ptolemy’s cluster. The colour of the stars in this cluster is predominately yellow, indicating this is an older cluster, with an estimated age of 260 million years. Clusters which contain many hot blue stars, like the Pleiades, are considerably younger.

Ptolemy Cluster on the 15/06/20 at 21:00pm. Image Credit: Stellarium Ptolemy Cluster. Image Credit & Copyright: Lorand Fenyes
The Jewel Box:

An open cluster the Jewel Box can be found very close in the Crux (Southern Cross) Constellation, the Jewel Box is located some 6,440 light years away from Earth and is 14 light-years across. The cluster contains just over 100 stars, and with an estimated age of its stars being just 14 million years, this star cluster is one of the youngest clusters that we’ve found. The Jewel Box cluster also has some of the brightest stars in the Milky Way galaxy. These stars are supergiants and the red, white and blue stars in the centre of the cluster look very much like the lights of a traffic light.

Jewel Box on the 15/06/20 at 9:00 pm. Image Credit: Stellarium The Jewel Box in perspective - Image credit: ESO, NASA/ESA, Digitized Sky Survey 2 and Jesús Maíz Apellániz
Eta Carinae and the Carina Nebula:

Variable brightness and Colour, Eta Carinae is one of the most remarkable stars in the heavens. When we say “Eta Carinae” we refer to the star itself which for Perth is a circumpolar star (We see the star all year round) and not the nebula.

Eta Carinae is 100 times the Sun’s mass and 4 million times brighter, those this brightness has been unstable with the star being recorded over the past 300 years between magnitude -0.8 which is as bright as Canopus and +7.9. It’s a star that’s sometimes in the news as it’s expected to become a supernova within the next 1 million years and will be a spectacular sight when it occurs, being visible by day and possibly bright enough to read by at night.

Eta Carinae is very likely a binary star with the smaller partner orbiting in a highly elliptical orbit of 5.5 years. The Carinae Nebula (NGC 3372), which surrounds Eta Carinae, is a large, bright star-formation region which has produced a number of very massive stars including Eta Carinae. At around 260 light years the Carina Nebula is around 7 times the size of Great Orion Nebula, but due to its greater distance, it only spans twice the width. There are many O-type stars, young (~2 million years), hot and bright that energise the entire Eta Carinae nebulae.

Carina Nebula on the 15/06/20 at 9:00 pm. Image Credit: Stellarium The Carina Nebula. Image Credit: Perth Observtory Volunteer Roger Groom Eta Carinae. Image Credit: NASA
Omega Centauri:

Omega Centauri or NGC 5139 is the largest and brightest globular cluster of 180 in Milky Way and is the second largest known, with only Mayall II in the Andromeda Galaxy being larger coming ins about twice its mass. The Globular cluster is located in Centaurus Constellation and it’s a naked eye ‘star’ and clearly visible in binoculars as a ‘fuzzy blob’. Omega Centauri contains at least 3 million stars and the cluster has a diameter of roughly 150 light-years and the stars are roughly 12 billion years old. The average distance between the stars at the centre is around 10% of a light year or more than 100 times the diameter of our solar system. It may be a dwarf galaxy that has been captured and disrupted by the Milky Way galaxy and measurements of its star movement by Hubble has indicated that a black hole may be located at the core of the cluster.

Omega Centauri on the 15/06/20 at 9:00 pm. Image Credit: Stellarium Omega Centauri. Image Credit: Perth Observtory Volunteer Andrew Lockwood

Phases of The Moon

June 2020 Moon phases

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