At first, the Sun lies within the constellation of Gemini, until 08h00 on the 20th, when it crosses the border into neighbouring Cancer. A significant
date, this month is that of the Earth’s Aphelion - July 4th, when at 12h, the Earth is at the furthest distance our planet can be from the Sun, 152 095 296 km (1.016694252 au) (centre to centre); ‘au’ is the symbol
for an astronomical unit; the mean (average) distance between the Earth and the Sun.
As in June, twilight persists all night, and the season for observing Noctilucent Clouds continues. Look towards the northern
sky during the two hours centred on astronomical midnight for these ethereal silvery veils in the northern sky.
Moon is at Apogee,
its furthest point from the Earth, on the 12th July at about 19h00. The angular diameter of the Moon is 30’ of arc. Perigee, when the Moon is at its nearest to Earth, is on the 25th at 05h. The angular diameter
then is 32' of arc.
Full Moon is on the 5th at 04h45 in the constellation of Sagittarius. There is a weak penumbral eclipse of the Moon, when the northern part of the Moon dips into the
penumbral shadow of the Earth. Areas of visibility include the Americas, western Europe and Africa just before sunrise. It is very unlikely that this event is noticeable.
Last Quarter Moon, on the
Cetus/Pisces border is on the 12th, at 23h30.
New Moon in July is on the 20th at 17h33, when the Moon passes 1.75° to the north of the Sun, on the Gemini/Cancer border.
First Quarter is on the 27th, at 12h33, when the Moon is on the Virgo/Libra border.
Look for Earthshine on the dark hemisphere of the
waxing crescent Moon from the 21st to the 26th, and on the waning crescent Moon from the 14th to the 19th.
Mercury is at inferior conjunction with the Sun on the 1st, and rapidly moves westwards to achieve its greatest elongation west of the sun (20°) on the 22nd. Around elongation, Mercury rises just before 03h00,
but twilight is increasing and is therefore difficult to see low in the ENE sky because of its low altitude and the increasing bright twilight.
At the start of July Venus rises 2 hours before the
Sun, and 3 hours before the Sun at the month’s end. The planet may be seen rising in the ESE sky at around 02h00, shining brilliantly as Phoshorus, the ‘Morning Star ‘of the ancients. It lies in the constellation of Taurus the Bull, passing
1° north of Aldebaran on the 11th/12th . The waning crescent Moon passes 3° south of Venus on the morning of the 17th. Venus at the moment is very much ‘The Harbinger of Dawn’!
Mars moves eastwards on the Pisces/Cetus border this month. Its magnitude increases from -0.7 at the beginning of July to -1.03 on the 31st. On the morning of the 12th the Moon, almost at last quarter, and
Mars, may be seen in conjunction and lie 3.45° apart, with fiery Mars to the upper right of the Moon producing a pleasant sight in the ESE sky in the early hours of the morning.
in the constellation of Sagittarius, and comes into opposition on the 14th. The giant planet is in conjunction with Pluto on the 3rd, when the faint Pluto, magnitude +14 lies 45 minutes of arc south of Jupiter. During this month, Jupiter
culminates at around astronomical midnight attaining an altitude of 14° above the south point of the horizon (from Scarborough, UK). Jupiter’s magnitude at this time is -2.75. Needless to say, this is a very good time to see the Galilean satellites
through well-focussed and firmly fixed binoculars, as they orbit the planet. At 01h on the 6th of the month, the Full Moon passes 3° south of Jupiter and with Saturn, lying 5.5° to the upper left of the Moon, the three form a pretty triangle
low in the southern sky. The comparative magnitude of the three bodies is as follows; Moon -12.5, Jupiter -2.72 and Saturn +0.9.
Saturn, on the Sagittarius/Capricornus border is at opposition on
the 20th, and as with Jupiter, is visible all night. It is interesting to notice how Jupiter is approaching Saturn as the rest of the year unfolds, until on the evening of the Winter Solstice, the two planets will be just 0.1° apart, the closest
approach of the two giant planets for many years. Enjoy the view of the northern aspect of the rings as they continue to be presented towards earth, although it is now noticeable that the north-south diameter of the rings is slowly reducing. If you wish to
see +8 magnitude Titan, Saturn’s largest moon, it may be seen at its greatest elongation east of Saturn on the 4th and the 20th, and its greatest elongation west of the planet on the 12th and the 28th. At these
times the distance between the two is approximately 200 seconds of arc.
Uranus is at visual magnitude +5.8 and liesin Aries. The best time to observe this remote world is around 02h, when it may
be seen at an altitude of 15° in the east at the onset of twilight. The path of Uranus amongst the faint stars of Aries may be seen on the charts on the Remote Planets page accessible via the Menu.
at visual magnitude 7,87 lies in eastern Aquarius just to the south of the Aquarius/Pisces border, below the ‘circlet’ of stars, which mark the position of the ‘western fish’. At 01h the planet is at an altitude of 18° in the ESE
sky, and its position amongst the faint stars of that region, as with Uranus, may be seen on the Remote Planets page.
Pluto is at opposition on the 15th, when it culminates (i.e. crosses
the south meridian) shortly after astronomical midnight. At this time, this magnitude +14.3 planet lies 1,5° to the east (left) of Jupiter, which is the brightest object in the midnight sky at this time. Saturn lies 5.5° to the east of Pluto, and all
three planets are in eastern Sagittarius’.
Pluto’s position in relation to the faint stars in this area of Sagittarius may be found on the Remote Planes page.
minor meteor showers take place at the end of the month. One is the alpha Capricornids, maximum July 30th – the zenithal hourly rate is 5. Many Capricornids are slow moving and colourful if you want to stay up and spot
some of them, and conditions are favourable.
On the 31st, we have the maximum of the southern delta Aquarids, with up to 20 a hour, and these meteors tend to be faint. Conditions this year are unfavourable.
Towards the end of July, the Perseid Meteor Shower begins, and continues towards its maximum on August 12th at 13h.
visible in the south around midnight, mid-month, are as follows: Sagittarius, Sagitta, Aquila, Lyra and Cygnus. The latter constellations contain Patrick Moore’s ‘Summer Triangle’, consisting of the three bright stars, Altair in Aquila, Vega
in Lyra, and Deneb in Cygnus. Cygnus is sometimes called the ‘Northern Cross’ because of the cruciform shape of its five main stars.
are GMT (UT). 1°is one finger width at arm’s length.
The phenomena of the month : JULY 2020
Times are given in UT for SCARBOROUGH (0° 25' 0" W, 54° 16' 3" N, zone UT).
Hour Description of the phenomenon
yyyy mm dd hh:mm
2020 07 01 02:53 INFERIOR CONJUNCTION of Mercury with the Sun (geoc. dist. centre to centre = 4.5°)
2020 07 01 09:16 Minimum of the variable star Algol (beta Persei)
2020 07 01 18:49 Minimum of the variable star beta Lyrae
2020 07 01 19:24
Maximum of the variable star delta Cephei
2020 07 02 12:24 Opposition of the asteroid 532 Herculina with the Sun (dist. to the Sun = 2.745 AU; magn. = 9.3)
2020 07 04 06:05
Minimum of the variable star Algol (beta Persei)
2020 07 04 12:00 The Earth at its aphelion (distance to the Sun = 1.01669 AU)
2020 07 05 01:00 Maximum of the variable star
2020 07 05 04:44 FULL MOON (penumbral eclipse of the Moon partly visible in SCARBOROUGH)
2020 07 05 22:23 Close encounter between the Moon and Pluto (topocentric
dist. centre to centre = 2.1°)
2020 07 07 02:53 Minimum of the variable star Algol (beta Persei)
2020 07 07 04:11 Maximum of the variable star delta Cephei
2020 07 07 23:25 Beginning of occultation of 39-epsilon Cap (magn. = 4.51)
2020 07 08 00:38 End of occultation of 39-epsilon Cap (magn. = 4.51)
2020 07 08 12:00 VENUS at maximum brightness (magn. -4.52)
2020 07 09 23:42 Minimum of the variable star Algol (beta Persei)
2020 07 10 06:53 Maximum of the variable
star zeta Gemini
2020 07 10 14:00 Venus at its aphelion (distance to the Sun = 0.72823 AU)
2020 07 12 00:52 Close encounter between Venus and Aldebaran (topocentric dist.
centre to centre = 1.0°)
2020 07 12 05:15 Maximum of the variable star eta Aquilae
2020 07 12 12:58 Maximum of the variable star delta Cephei
2020 07 12 19:27 Moon at apogee (geocentric dist. = 404199 km)
2020 07 12 20:31 Minimum of the variable star Algol (beta Persei)
2020 07 12 23:29 LAST QUARTER OF THE
2020 07 13 00:06 Opposition of the asteroid 2 Pallas with the Sun (dist. to the Sun = 3.370 AU; magn. = 9.6)
2020 07 14 07:59 OPPOSITION of Jupiter with the Sun
2020 07 14 17:23 Minimum of the variable star beta Lyrae
2020 07 15 12:48 Opposition of the asteroid 129 Antigone with the Sun (dist. to the Sun = 2.390 AU; magn. = 9.9)
2020 07 15 17:19 Minimum of the variable star Algol (beta Persei)
2020 07 15 19:11 OPPOSITION of Pluto with the Sun
2020 07 17 21:45 Maximum
of the variable star delta Cephei
2020 07 18 14:08 Minimum of the variable star Algol (beta Persei)
2020 07 19 02:28 Close encounter between the Moon and Mercury (topocentric
dist. centre to centre = 3.1°)
2020 07 19 09:29 Maximum of the variable star eta Aquilae
2020 07 20 10:29 Maximum of the variable star zeta Gemini
2020 07 20 17:33 NEW MOON
2020 07 20 22:28 OPPOSITION of Saturn with the Sun
2020 07 21 10:56 Minimum of the variable star Algol (beta Persei)
2020 07 23 00:00 GREATEST WESTERN ELONGATION of Mercury (20.0°)
2020 07 23 06:32 Maximum of the variable star delta Cephei
2020 07 24 07:45 Minimum of the variable
star Algol (beta Persei)
2020 07 25 04:54 Moon at perigee (geocentric dist. = 368361 km)
2020 07 26 13:43 Maximum of the variable star eta Aquilae
2020 07 27 04:34 Minimum of the variable star Algol (beta Persei)
2020 07 27 12:32 FIRST QUARTER OF THE MOON
2020 07 27 15:54 Meteor shower : Piscis Austrinids (5
meteors/hour at zenith; duration = 26.0 days)
2020 07 27 15:58 Minimum of the variable star beta Lyrae
2020 07 28 15:19 Maximum of the variable star delta Cephei
2020 07 29 18:07 Meteor shower : Alpha Capricornids (5 meteors/hour at zenith; duration = 43.0 days)
2020 07 29 18:07 Meteor shower : S. Delta Aquarids (25 meteors/hour at zenith;
duration = 43.0 days)
2020 07 30 01:22 Minimum of the variable star Algol (beta Persei)
2020 07 30 14:04 Maximum of the variable star zeta Gemini
Generated using COELIX software