Night Sky Notes – June 2017

Night sky notes for June 2017​               Geoff Mitchell

The June night sky shows almost continuous twilight , the summer constellations rising mid evening, the summer solstice on June 21st marks he shortest night The bright planet Jupiter in the constellation of Virgo is now low in the southwest by early evening and the ringed planet Saturn is seen low in the south east in the constellation of Ophiuchus. Currently Saturn has rings are nicely open also showing the North Polar Region. Comet 2015 V2 (Johnson) is a telescopic object moving through the constellation of Bootes during month (see notes)

The summer night sky contains many fine objects to view for the enthusiast in the midnight hours but also has a few notable events of special interest. During June look to the NW some 90 to 120 minutes after sunset or to the NE 90 minutes similarly before sunrise. This when the Sun is just below the horizon during the summer months , under favourable conditions extremely high clouds at 80 km altitude known as Noctilucent Cloud (NLC) may be seen. NLC’s show a bluish colour and also show filamentary structure.

In the south west the constellation of Virgo as twilight fades contains the white star Spica and the brighter planet Jupiter located above and to the west of Spica. Small telescopes show up to four prominent Galilean moons Io, Europa, Ganymede and Callisto as well as the famous cloud belts. The Great Red Spot (GRS) is less prominent and may require larger telescopes to see at favourable times – Jupiter rotates in just under 10 hours.

Our own Milky Way galaxy stretches from the constellation of Auriga [The Charioteer], marked by the bright star Capella through the constellations of Perseus and Cassiopeia all now positioned low in the north. In the east however the summer constellations of Cygnus [The Swan or Northern Cross] now rises by late evening. The bright star Vega in the adjacent constellation of Lyra [The Lyre] is seen in the north east and Altair in the constellation of Aquila low in the east by late evening. Vega, Altair and Deneb, in the constellation of Cygnus form the `Summer Triangle` asterism, a useful sign post for the summer skies. Look with binoculars along the central axis of Cygnus , down through Aquila into the south and see the rich star fields of Scutum and Sagittarius , with the famous `Teapot ` asterism, low in the south in the early morning hours in June and late evening in July.

Adjacent to Lyra the familiar `keystone asterism ` of the constellation Hercules is noted for the Globular clusters M13 and M92 the former containing some 750,000 stars, a nice view in a small telescope .

Scorpius [The Scorpion] in part is visible low in the south as twilight fades. Use binoculars to see the myriad of stars in these rich star clouds, best seen on clear dark moonless evenings from darker locations outside the town or remember to take your binoculars with you if you’re on your holidays. The red star Antares, as the name means `rival to Mars ` currently this can be compared with the planet Mars which appears to move retrograde to the stars in Scorpius into Libra and still shining brightly (magnitude -1.6m) post opposition.

Look low in the SE late evening to find a yellowish star to the east of Scorpius ( noted by the red star Antares ) . The yellow star is in fact the ringed planet Saturn which reaches opposition in early June in the constellation of Ophiuchus [The Serpent Bearer]. Although rather low as seen from the UK in June, modest telescopes give a classic view of this gem of the solar system and will show the rings and the brightest moon Titan. Larger telescopes show up to six or so fainter moons and any white oval features on the planets disk and some of the ring detail such as Cassini Division etc. Observe the Seeliger Effect around opposition to mid and note any brightening of the ring system due to the ring particles angle of illumination changing causing the apparent brightening.

The familiar asterism of the plough in the constellation of Ursa Major, The Great Bear is seen high overhead with its handle or tail pointing upwards mid evening. Use the right hand pair of stars Dubhe and Merak (The pointers) to find the faint pole star Polaris and the position of North.

High in the east the bright orange star Arcturus in the constellation of Bootes [The Herdsman] is the brightest star in the northern hemisphere of the sky. Between Arcturus and the Keystone asterism in Hercules lies the `U` shaped constellation of Corona Borealis [Northern Crown].

 

Planets in June 2017

Mercury poorly placed in evening twilight skies from mid June is in Conjunction with Mars is on June 28th.

Venus is in our dawn skies reaching maximum elongation on June 3rd

Mars is poorly placed low in evening twilight, heading into the daytime sky by late June.

Jupiter is seen shining brightly in the southwest in evening twilight.

Saturn now at opposition (June 15th) rises by mid evening in Ophiuchus low in south. Although it is low in our June skies but has the ring system open at 26 degrees – a classic view of this `gem ` of the solar system.

Uranus is not visible in daytime skies – best views in autumn skies.

Neptune is not visible in daytime skies – best seen in autumn skies

Moons phases in June 2017

New Moon ​June 24th ​Moonless, best time for deep sky and Milky Way observing.

First Quarter June 1st ​Best days to see shadow details in lunar craters (early evening) **

Full Moon ​June 9th ​Best days to see bright ray craters like Copernicus / Tycho.

Last Quarter ​June 17th ​Moon visible in daytime skies. Do not look directly at the Sun.

Meteor shower s Ophiuchids – peak June 10th to June 20th – low rates – rather unfavourable. ​ June Lyrids, peak June 16th – unfavourable

The highlights of the month.

Saturn at opposition low in south east by late evening , rings open at 26° DE [tilt] showing Saturn’s North Pole.

Jupiter at 23:00 BST on June 5th shows the double shadow transit of Jupiter’s moons Io and Europa [20cm telescope or larger} (See Notes)

Blood red star Antares in the constellation of Scorpius low in the south in the late evening sky

Noctilucent cloud –watch the NW skies 90 to 120 minutes after sunset .

Summer solstice June 21st 05h 25m BST, earliest sunrise June 17th and latest sunset of the year June 25th.

Waxing crescent Moon visibility ​Earliest visible waxing 6.4% crescent Moon from Luton is June 25th, look low close to the NW horizon from 15 minutes after sunset from around 21:45 BST until moonset at 22.:27 BST 21:16. Caution. Do NOT look at the Sun directly with or without optical aid.. ​

Note the waxing crescent Moon has a dimly lit part made visible by Earthshine is readily seen with binoculars or small telescope. Only look for the crescent Moon after the sun has completely set.

More detailed sky notes and LAS Newsletters, Finder charts are available to LAS members via the Members` page on the LAS Website http://www.lutonastrolink.org.uk Artificial satellite and International Space Station visible passes and bright Iridium flares – check the home page for posting s of details of favourable observing times.

 

Sky looking south at 11pm British Summer Time (BST), mid June 2017

 

In the south the ringed planet Saturn lies in the constellation of Ophiuchus to east of the `T` shaped asterism of the head of Scorpius. From the UK we only see the head; the rest of the constellation is visible from more southerly locations. Catch a glimpse in June of the bright red star Antares on the stem of the `T` asterism low in the south east. Binoculars / small telescopes also show some nice star fields in Scorpius.

Looking at Virgo we look outside our own Milky Way galaxy towards the external galaxies of the Virgo Cluster , look to Sagittarius to into the spiral arm of our own galaxy, the centre of our own galaxy is however too far south to see from the UK

The orange star Arcturus is found by following the curve of stars in the handle of the Plough down. The constellation of Bootes, resembles a `kite` or `Club ` in shape. The star Izar is a beautiful orange/ blue double star visible in small telescopes. To the east of Bootes find the `horseshoe` shaped constellation of Corona Borealis (Northern Crown) and the `Keystone` Asterism in the constellation of Hercules. Hercules also has M13 the famous Globular Cluster, visible to the unaided eye as a misty patch; telescopes show the true wonder of this cluster with over 750,000 stars. Likewise another nice globular is M92 in Hercules.

Two comets, periodic comet 41P (Tuttle-Giacobini –Kresak) and Comet 2015 V2 Johnson head southward during the month and are difficult telescopic / binocular low surface brightness objects in June twilight skies

Sky looking east at 11pm BST mid June 2017

 

In June the summer constellations of Lyra and Cygnus are rising by mid evening, the Milky Way may be visible on moonless evenings from a dark site, subject to twilight. Binoculars show the rich star fields of the Milky Way.

The Summer Triangle asterism formed by the three bright stars Vega, Altair and Deneb is a useful guide for finding your way around the summer night sky

 

Sky looking north at 11pm BST mid June 2017

 

The Plough stands with its handle pointing upward follow the pointer’s Dubhe and Merek to find the polestar Polaris. The `W` shaped constellation of Cassiopeia is at its lowest point in the north late evening. The Milky Way follows the galactic equator and stretches from east through the constellations of Cygnus, Cassiopeia, Perseus and down into the northern horizon.

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Sky looking west at 11pm BST mid June 2017

 

 

Night sky highlights of the month June 2017

Saturn visible low in the SE late evening, reaches opposition in mid June the planet shows nice ring detail and northern polar region. Titan is the brightest of Saturn’s moons which is visible in a small telescope and moves from evening to evening with respect to the planet, orbiting Saturn in just 15.9 days.

WINJOPOS software prediction for telescopic view Saturn’s moons for June 14th (Titan is the brightest) and Jupiter at 23:00 BST on June 5th showing the double shadow transit of Jupiter’s moons Io and Europa.

 

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