by Anne Holt Sunrise 1st: 04.46 30th: 04.44 Sunset 1st: 21.27 30th: 21.40 Astronomical darkness: none. In the later part of the month we only have about 2 hours of astro twilight. Day length 1st: 16.41.24 30th: 16.58.42 Longest day 20th: 17.01.50 (21st is less than 1 second shorter) Earliest Sunrise 17th: 04.39 Latest Sunset 24th: 21.42 The
Summer Solstice, when the Sun reaches its most northerly point in the
sky, is on 20th at 22.27. On this day the Sun is overhead at local noon
along the Tropic of Cancer. Full Moon 5th at 20.12 (366564 Km) New Moon 21st at 07.42 (387066 Km) Lunar perigee 3rd (364365 Km) 30th (368957 Km) Lunar apogee 15th (404596 Km) June's full Moon is known as the Strawberry Moon. Other names are the Rose Moon, Hot Moon, Mead Moon and Honey Moon. On
5th June there is a partial penumbral lunar eclipse. There will be
only a very slight darkening of the right hand side of the Moon's disc
as it passes through the outer part of the Earth's shadow. And, even
worse, from Manchester the eclipse will be almost over when the Moon
rises at 21.21 - it finishes at 22.04 when the Moon is still only 4
degrees above the SE horizon. On 21st
there is an annular solar eclipse, visible only from parts of Africa,
the Middle East and Asia. An annular eclipse occurs when the Moon is
fairly close to apogee so does not appear large enough to completely
cover the Sun. On this occasion the Moon will have 99.5% the diameter
of the Sun so, at maximum, will leave only a very thin 'ring of fire'.
The best view will probably be from Tibet where the high altitude means
clear air and clear skies. Highlights Not
much in the way of highlights again this month. As always in June, the
main problem is too much light, no astronomical darkness and very
little astro twilight. Mercury starts the month a day past its highest
point in the evening sky but is still very low as the sky darkens.
Early risers fare a little better, Jupiter is still very bright in the
early hours and Mars is brightening and getting higher in the pre dawn
sky. We have about 40 minutes of a partial penumbral lunar eclipse and
an annular solar eclipse which isn't visible at all from here. And
C/2020 F8 (SWAN) is the latest in a long line of comets which fail to
live up to earlier promise. However, we might see some ... Noctilucent Clouds The
season for observing these thin, wispy clouds runs from late May to
early August. They may, if we're lucky, be seen in the north to NW,
about 60 to 90 minutes after sunset, and in the north to NE, 90 to 60
mintes before sunrise, when the Sun is about 6 degrees below the
horizon. They are usually blue and silver but occasionally red or
orange. They are composed of ice crystals in the mesosphere about 50
miles up - so high that they are still in sunlight when the Sun has set
for observers at ground level. They are formed when water
vapour condenses on to dust particles and freezes in the very low
temperatures, around minus 120 degrees C. Some of the water
vapour may be moisture from gaps in the troposphere but it is thought to
be predominantly produced by chemical reactions involving methane.
Displays became more prominent in the first half of the 20th century
when the amount of methane in the upper atmosphere increased. The
dust is mostly of meteoric origin, though some could be atmospheric
pollution, the first recorded sighting of the clouds was in 1885, soon
after the eruption of Krakatoa. As well as high methane
levels increasing the amount of moisture in the mesosphere, the amount
of carbon dioxide also affects the formation of NLCs, high levels of the
gas make it even colder which helps the ice crystals to form. Displays are stronger and more frequent when, as now, we are close to solar minimum. Last
year we had some exceptional displays, the clouds were seen much
further south than ever before, however recent atmospheric studies have
suggested that 2020 won't equal these, so we should expect only average
displays. But, recent satellite images have shown the first
faint NLCs of the season, above the Arctic Circle, on May 17th, this is
very early so you never know. Update: these are now intensifying for up to date information see Constellations The Plough asterism in Ursa Major is still prominent, being overhead for much of the night, leaving Cassiopeia on the opposite side of the Pole Star, low in the northern sky. The Summer Triangle, consisting of Vega, Deneb and Altair, is now getting higher in the late evening, though Altair, in Aquila, is still quite low in the early part of the night. The beautiful double star Albireo, at the head of Cygnus the swan, is very well placed for observing. The Milky Way is now visible from dark sky sites, running across the sky through the Summer Triangle, passing almost overhead in the early hours. The bright orange red Arcturus is shining brightly high in the SW and, if you manage to find some dark skies not obscured by cloud, you should be able to see the rest of the kite shaped Bootes, with the semicircle of stars forming Corona Borealis just to the east of it. Another red giant, Antares in Scorpio is now visible low on the southern horizon. Planets Mercury: in Gemini, mag 0.1 Not
easy to see this month. On 1st it is only 7 degrees above the horizon
at dusk, setting at 23.29, a couple of hours after the Sun. It reaches
greatest eastern elongation on 4th, when it appears separated from the
Sun by 23.6 degrees but only 15 degrees above the horizon at sunset,
down to 6 degrees by the time the sky darkens. From mid June it is
below the horizon at dusk. It also fades during the month and on 22nd it
is down to mag 3.2 and appearing only 13 degrees from the Sun. It is
at aphelion, the furthest point in its elliptical orbit from the Sun, on
23rd, when it is at a distance of 0.47 AU. On 30th it sets 20 minutes
after the Sun and the apparent separation is only 4 degrees. Venus: in Taurus, mag -3.8 Not
visible in early June. On 1st it sets less than half an hour after the
Sun and is separated by only 4 degrees. It reaches inferior solar
conjunction on 3rd, passing less than half a degree north of our star.
It then becomes a morning object but too low in the dawn sky to be
visible. On 19th at 08.40 (from the centre of the UK - couldn't find
local time) in daylight, the planet is occulted by the thin crescent
Moon. At dawn on that day the pair are separated by less than a degree
but only 2 degrees above the horizon. On 30th Venus has brightened to
mag -4.4, rising at 03.08 and reaching 7 degrees as the sky brightens. Mars: in Aquarius, mag 0.0 On
1st when it rises at 02.14 and should be visible from 03.30, when it reaches
12 degrees in the SE. On the morning of 13th, the 51% Moon passes 3
degrees south of the planet, now at mag -0.2, in the early hours. If
you look through binoculars you might have a chance of seeing the much
fainter Neptune 1 degree 44' to the north. WARNING: the Sun
rises soon after 4.30 on this day so be sure to put your binoculars away
in good time. Looking at the Sun, even for a few seconds by accident,
through binoculars could result in permanent blindness. Mars
moves into Pisces on 25th, where it rises at 01.27 and reaches 21 degrees
by dawn. On 31st it is at mag -0.5, rising at 00.52 and getting to 24
degrees in the SE as the sky brightens. Jupiter: in Sagittarius, mag -2.6 Still
shining brightly in the morning sky. On 1st it rises at 00.24 and is
visible from 01.45 till dawn, when it is at 14 degrees in the south. On
8th the 89% Moon passes just over 2 degrees south of the planet, they
are closest at 18.46 while still below the horizon but not much further
apart on the morning of 9th. During the last week in June, Jupiter is
less than 1 degree north of Pluto. They are in conjunction (having the
same right ascension) on 25th at 19.32 but at their closest on the
morning of 27th. On this day Jupiter rises at 22.32 and reaches 14
degrees in the south at 02.32. Unfortunately Pluto will be too faint to
be easily imaged at this low altitude. On 30th Jupiter has brightened
to mag -2.7, rises at 22.19 and reaches 8 degrees in the SE by 23.45,
culminating at 14 degrees at 02.18. Saturn: in Capricorn, mag 0.4 Still
low in the morning sky. On 1st it rises at 00.37 and should be high
enough to be seen by around 02.30 and getting to 15 degrees in the south
by dawn. On 9th the Moon passes 2 degrees 38' south of the planet at
03.53, with Jupiter also close by, a few degrees to the west. The Moon
will be 86% lit, so no smiley face. By 30th Saturn will be at mag 0.2,
rising at 22.35 and culminating, 16 degrees above the southern horizon,
at 02.44. Uranus: in Aries, mag 5.9 Not
visible this month. On 1st it rises at 03.31 but is still 10 degrees
below the horizon at dawn. It does improve during the month but is
still only just on the horizon at daybreak on 30th. Neptune: in Aquarius, mag 7.9 On
1st it rises at 02.17 and is still below the horizon when the sky
begins to brighten. On 12th at 13.18 Mars passes 1 degree 44' south of
the fainter planet, they are still close on the morning of 13th, when
Neptune rises at 01.30 but doesn't get high enough in darkness to be an
easy binocular target. On 30th it rises at 00.24 and gets to 9 degrees
by dawn, still a bit too low for observing. Dwarf Planets Ceres: in Aquarius, mag 9.0 Rises
at 03.01 on 1st but is still very low in the SE by dawn. On 30th it
rises at 01.27, has brightened to mag 8.6 but still doesn't get high
enough for imaging or observing. Pluto: In Sagittarius, mag 15.0 Orbiting
in the Kuiper Belt, the faint, distant Pluto is much too low to be
successfully imaged, even towards the end of the month when it is very
close to Mars. Haumea, in Bootes, mag 17.3, and
Makemake in Coma Berenices, mag 17.1, are much higher in the sky and a
better bet for ambitious, experienced amateur astrophotographers,
despite being so distant and faint. On 1st Haumea is at 50 degrees in
the SW around midnight, Makemake reaches a similar altitude. By month
end the highest points in darkness are 32 degrees and 27 degrees in the
west respectively. Eris: in Cetus, mag 18.8 The faintest, most distant of the currently recognised dwarf planets is below the horizon all night throughout June. Asteroid
7 Iris, in Sagittarius, reaches opposition on 28th. On this day it is
at mag 8.9 and culminates at 01.14 but is only 15 degrees above the
southern horizon. Comets C/2019 Y4 (ATLAS) in Taurus. Originally
predicted to be a candidate for Comet of the Century, then it broke
up. But the 4 main pieces are still going and are quite bright at
magnitudes ranging from 3.8 to 5.9. But we can't see them, as they are now too close to the Sun. C/2017 T2 (PANSTARRS) in Ursa Major, mag 8.8 Circumpolar
at the start of June, and reasonably high during the hours of darkness .
By 6th it is quite low for part of the night and best seen between
midnight and 2am. Moves into Canes Venatici on 25th, when it will have
faded slightly and only be high enough from 01.00 to 01.30. On 30th it
is predicted to have faded to mag 9.2 and will be best positioned
between 00.40 and 01.40. C/2020 F8 (SWAN) in Auriga, mag 6.4 Yet
another which hasn't lived up to expectations, estimates now a couple
of magnitudes less than previously given. On 1st it is circumpolar, just
over 1 degree SW of Capella, only 11 degrees above the horizon as the
sky darkens. It is moving south westwards, getting lower in the evening
sky. On 23rd it moves into Lynx and is only 9 degrees at dusk. It goes
back into Auriga on 28th and on 30th, now with an estimated mag of
8.1, appears only 9 degrees from the Sun. For more info and exact positions of any solar system objects see I usually recommend www.cometwatch.co.uk but as it hasn't been updated since April 20th, maybe not. If I've missed any current comets - blame them! Meteor Showers Not
a good month for meteor spotters. The antehelion source may provide one
or two, especially in early and late June but the radiant, moving
across Sagittarius, is very low for observers in the northern
hemisphere. June Bootids, active (maybe)
June 22nd to July 2nd, peak on the night of 27th around 23.00. ZHR is
variable, given as anything between zero and 30, but this year is
predicted to be at the lower end of that range, though there could
possibly be some activity on 23rd. The parent comet of these slow
moving meteors is 7P/Pons-Winnecke. June Lyrids, peak 15th/16th. Not much activity from these in recent years. There are a few daytime showers: Zeta
Perseids, active May 20th to July 5th. peak 9th (or maybe 13th). This
shower, parent comet 2P/Encke, was first discovered at Jodrell Bank in
1947. Beta Taurids, active June 5th to July
18th, peak 28th. ZHR said to be 'weak' or 'modest' but it is thought
that the Tunguska meteor in June 1908 could have been associated with
this shower. Daytime Arietids, active May 14th to June 24th, peak June 7th, ZHR 30. A few of these may be spotted visually in the morning twilight but the radiant is only 30 degrees west of the Sun. |