In Manx skies... August 2017 ~ compiled by Dave Storey


21st at 18.30h

First Quarter
29th at 08.13h

7th at 18.11h

Last Quarter
15th at 01.15h

© Copyright

Note: All times are Universal Time (UT)
British Summer Time is now in force. Remember to add 1 hour to any times quoted here to get local IoM time.

There is a partial lunar eclipse on the 7th .

The beginning of eclipse starts at 15h50m when the Moon is below the horizon. At that time, the pen-umbral shadow of the Earth will contact the Moon's disc. The umbral shadow of the Earth will cross the lunar disk between 17h22m to 19h18m and none of this will be visible as the Moon will still be below the horizon. Moon rise occurs at 19h53m and the pen-umbral shadow will be positioned across ¾ of the Moon's disc on the right side. As the Moon continues to rise, the pen-umbral shadow will move off the disc; ending at 20h51m. The altitude of the Moon will be low at 6° at end of eclipse. So not a favourable eclipse to observe from the Isle of Man.
For further details, click here.

There is a total solar eclipse on the 21st .

The total eclipse is visible across North America and only a partial solar eclipse will be seen from the Isle of Man. Taking timings from a position where maximum solar eclipse occurs (36.97°N, 087.67°W), the Moon starts to cover the Sun's disc at 16.56h. As seen from the Isle of Man at this time, the Moon will still be 1.2° to the right of the Sun! When maximum eclipse occurs in the USA at the above coordinates (18.25h UT), the Moon will still be slightly lower right of the Sun as seen from the IoM.
It will not be until 18h38m40s when the Moon will start to enter the solar disc as seen from the Isle of Man. At this time, the centre of the lunar eclipse shadow will be centred over the town of Clemson, South Carolina (34.67°N, 083.83°W). Altitude of Sun at start of partial eclipse from IoM will be 7.2° and the maximum disc covered by the Moon will occur at 19.00h with only 8% of the Sun's disc is covered. See above graphic. Maximum partial eclipse occurring with the Sun only 4° above the horizon. The Moon leaves the Sun's disc at 19h23m34s when the Sun is less than 1° above the horizon.
For further details, click here.


Solar activity is low with solar cycle 24 now in force.


Carrington's Solar Rotation number 2194 starts on the 16th at 11h26m17s.


Is very low down in the west after sunset at the start of the month and will be extremely difficult to see due to the bright twilight sky. It moves towards the Sun and passes through inferior conjunction on the 27th when it passes about 4° south of the Sun. It is therefore not well placed for viewing this month.


Is a morning sky object shining at magnitude -4.0 at the start of the month and fading slightly to -3.9 by months end. There is a conjunction with the thin crescent Moon on the morning of the 19
th . The planet will be seen about 3° to the upper left of the 9% illuminated Moon and should prove a nice naked eye and binocular view. As seen through a telescope, Venus will have an apparent disc diameter of 14.6 arc seconds and illuminated phase of 74.4% on the 1st. The planets disc size shrinks to 12.5 arc seconds by the 31st and will have a phase of 83.4%.


Is poorly place for viewing this month as it is on the far side of the solar system and too close to the Sun.


Will be found low down in the south-west after sunset shining at magnitude -1.9 in the constellation Virgo. It is about 7° to the upper right of the bright star Spica on the first and by the end of the month, the planet will have moved closer to a distance of about 3° by the 31st. Of the 2, Jupiter will be the brighter object as Spica is of magnitude +1.0 as opposed to Jupiter's magnitude -1.7

The waxing crescent (18% illuminated) Moon joins Jupiter and Spica on the evening of the 25th and should prove a nice binocular sight.


The planet resides in Ophiuchus all month, shining at magnitude +0.3 to +0.4. It is low down when it transits the sky due south and this will mean any telescopic viewing of the planet will be spoiled by poor seeing conditions. The rings are well open towards Earth at an angle of +26° and should prove a lovely sight. The waxing gibbous Moon will be 9° upper right of Saturn on the evening of the 2nd.


alpha-Cygnids became active during July and continue into August. There is the second peak of activity on the 21st when 5 meteors per hour (ZHR) will be seen. Radiant is at RA. 21.00h Dec. +48°

Capricornids were active during July and continue in August. There were three peaks of activity in July and August will consist of the tail end of this weak shower. These meteors can display yellow-blue colours. Radiant is at RA. 20.44h Dec. -15°

delta-Aquarids continue from July until 20th August. A second peak of activity occurs 6th August. The peak will be 10 meteors per hour (ZHR) and situated at radiant RA. 23.04h Dec. +02°. These meteors are usually faint.

Alpha-Capricornids were active from July and continue to 20th August. Peak activity is low, occurring on the nights 2nd - 3rd . With only 5 meteors per hour (ZHR), it is still worth a watch as this shower produces some long, slow moving fireballs. Radiant is at RA. 20.36h Dec. -10°

iota-Aquarids continue to be active from July and into August with a peak due 6th August. This is another weak shower with only 8 meteors per hour (ZHR) at peak. The near Full Moon will spoil the viewing on night of peak activity. Radiant is at RA. 22.10h Dec. -15°

Perseids are active this month with a peak occurring on the 12th at 19.00h. Peak rate is 80+ meteors per hour (ZHR). The moon will spoil the viewing somewhat as it will be 72% illuminated on the night of maximum. This meteor shower produces some bright events with long lasting trains. Radiant is at RA 03h13m Dec. +58°

(Stars Brighter than Magnitude +6.0)

Date Time      ZC#    SAO#           Magnitude.    P.A.     Type of event.    Notes

5th 00:50:25 2734    SAO 187324    5.2            117    DD            D* Moon Low

6th 21:13:53 2981    SAO 163592    5.1            072    DD            M* Moon Low

13th 23:57:34 364   SAO 110543     4.3            278    RD

15th 03:46:48 508    SAO 93469     4.1            280    RD             5 Tau. D*

16th 02:38:57 661    SAO 93932     4.5            246    RD            71 Tau. M*

16th 03:43:05 669    SAO 93955     3.8            288    RD             theta 1 Tau. M*

16th 03:47:05 671    SAO 93957     3.4            266    RD             theta 2 Tau. M*

16th 03:57:16 675    SAO 93970     5.6            179    RD             80 Tau. D*

16th 06:45:05 692    SAO 94027     0.9            022    DD             Aldebaran M* Daylight

16th 07:27:18 692    SAO 94027     0.9            311    RD             Aldebaran M* Daylight

17th 01:41:03 806    SAO 94526    5.0             191    RD            111 Tau. M*

17th 03:05:09 814   SAO 94554     5.4             306    RD             115 Tau. M*

Click on date/time to display graphic of occultation event.

For very detailed list of occultations visible this month, click here. (Data from Occult Software)

Times are UT as seen from IoMAS Observatory. Start to observe these events about 20 minutes before the above times to allow for differences in your latitude and longitude. This will give you time to locate the star that is about to be occulted.

ZC = Zodiacal Catalogue. Type of Event DD = disappearance at dark limb, RD = Reappearance at dark limb. RB = Reappearance on bright limb. PA = Position Angle around limb of the Moon, where 0 degrees is north, 90 degrees is east, 180 degrees is south and 270 degrees is west.
D* = Double Star M*=Multiple Star.

The above predictions were calculated from Occult software by David Herald. More information regarding this software may be found at the web site.


This star drops from magnitude +2.1 to +3.4 in about 5 hours. Suitable events visible from the Isle of Man this month occur on 17th at 00.42h. Click here for a star chart for Algol.

(Brighter than +10)

There are no predicted bright comets this month.


The international Space Station crosses the Manx skies on a regular basis. For the latest information on when the ISS is due to pass across the sky over the next ten days, visit the link below.

ISS transit Information from Heavens

Bibliography for Manx Night Skies

The Handbook of the British Astronomical Association 2017. BAA. 2016
Stargazing 2017. Heather Couper & Nigel Henbest. Philip's 2016
2017 Guide to the Night Sky. Storm Dunlop & Wil Tirion. Collins 2016
2017: An Astronomical Year (U.K. Edition) Richard J. Bartlett. October 2016
Yearbook 2017. Sky at Night. BBC. Immediate Media Company, Bristol. 2016
2017 Yearbook of Astronomy. Richard Pearson & Brian Jones. CPI Group (UK) Limited. 2017
Observer's Handbook Meteors. Neil Bone. Philip's 1993
Atlas of the Night Sky. Storm Dunlop. Collins. 2005
Constellations. Josef Klepešta and Antonin Rükl. Hamlyn. 1979
Brilliant Stars. Patrick Moore. The Book People Ltd. 1996
Complete Guide to Stargazing. Robin Scagell. Phillip's. 2006
Turn Left at Orion. Guy Consolmango and Dan M. Davis. Cambridge U.P. 2008
Norton's 2000.0 Edited Ian Ridpath. Longman Scientific & Technical. 1989

Planetary data derived from Guide 9 Software.
Picture graphics derived from Stellarium and Guide 9 Software.