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


25th at 19.44h

First Quarter
3rd at 02.47h

10th at 21.42h

Last Quarter
19th at 00.19h

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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 are no Lunar or Solar eclipses this month.


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


Carrington's Solar Rotation number 2191 starts on the 26th at 20h29m07s.


Is in the morning sky, rising shortly before sunrise. It will be a difficult to view this month due to its low elevation and bright dawn sky. The planet will reach greatest western elongation on the 17th when it will be 26° to the right of the sun.


Will be found rising at 03.28h on the first, shining at magnitude -4.7. The planet will be increasing its elongation (apparent angular distance) from the sun throughout the month with greatest elongation in June. By months end, the planet will fade slightly to magnitude -4.5 and will be rising at 02.27h. As seen through a telescope, the planet will have an illuminated phase of 26.9% and apparent disc size of 37.9 arc seconds on the 1
st . The planet will be moving away from Earth during the month and will be 24.8 arc seconds wide by the end of the month and phase of 47.9%. The 15% crescent Moon will be in conjunction with Venus at 15.19h on the 22nd. On this date, it may be a good challenge to see Venus in the daytime sky. If you can find the crescent Moon in the sky, you should be able to pick out Venus about 3° upper left of the Moon using a pair of binoculars. Once you find Venus in binoculars, see if you can spot Venus with your naked eye. It can be done. WARNING: Of course, make sure you are standing in the shadow of a building before searching the sky so as to ensure you don't accidentally observe the Sun.


Is in Taurus throughout the month shining at magnitude +1.6 to +1.7. The planet is on the far side of our solar system and will present a very small apparent disc diameter as seen in a telescope. (less than 4 arc seconds). The opportunities of seeing Mars will get worse as the month progresses and by the second half of the month, Mars will become lost in the bright evening twilight sky just after sunset.


Is well placed for viewing in Virgo this month having just gone through opposition last month. As soon as the sky is dark enough after sunset, you will easily find bright Jupiter towards the south east. There is a close conjunction of Jupiter with the Moon on the 7th at 22.42h when the Moon will pass just over 1° north of Jupiter. This will make an excellent naked eye and binocular sight and also a photo opportunity.

As the moons orbit Jupiter, there are occasions when the shadow of the moons can be seen upon the surface of Jupiter and the moons can transit across Jupiter's disc. Also, the moons can be seen to be occulted or eclipsed by Jupiter. There are many events throughout the month. See periodicals such as the BAA Handbook, Astronomy Now and Sky at Night magazines for listings.

The Great Red Spot may be seen using a telescope in good seeing conditions. Using a light blue filter with an eyepiece will help. Opportunities to see the Great Red Spot from Mann occur on a regular basis. Click here for suitable dates and times.

To help you identify the moons at any particular time, Sky and Telescope have a Java tool that will plot the moon positions. Click Here.


 Best seen just before dawn this month. It is in the constellation Sagittarius at the start of the month shining at magnitude +0.3. It will be seen moving in a retrograde (east to west) direction and on the 18th, it will move into the constellation Ophiuchus. By months end, the planet will be shining at magnitude +0.1, rising at 21.28h.

The brightest moon of Saturn, Titan will be visible in telescopes, shining at magnitude +8.5 and will be east of the planet on 10th ,11th ,12th , 13th ,26th , 27th ,28th and 29th .It will be west of the planet on 3rd ,4th , 5th , 19th ,20th and 21st


eta-Aquarids are active until the 20th with a maximum due on the 5-6 May. Zenithal Hourly Rate ( ZHR ) is 40 meteors per hour. Radiant is at RA 22h30m Dec. -01° These meteors originate from Halley's comet and enter the earth's atmosphere at 42 miles per second.

Alpha-Scorpids are active until the 19th May with a peak activity occurring on the 12th. ZHR is low at on 5 meteors per hour. Radiant is at RA 16h04m Dec. -24°

Ophiuchids are active during May with maximum due in June. The shower is however weak.

(Stars Brighter than Magnitude +6.0)

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

4th  00.52:55      1439    98755         +5.7           148° DD                 18 Leo
4th  23.12:01      1550    118300       +5.6           124° DD                 49 Leo D*

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 T* = Triple 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. There are no suitable dates for observing this month. Click here for a star chart for Algol.


Comet C2015 V2 (Johnson) remains brighter than magnitude 10 this month, increasing in brightness from +7.4 to +6.7. It will be travelling through Hercules until the 3rd when it will move into Boötes for the remainder of the month. Click here for an ephemeris.

Comet 41P (Tuttle-Giacobini-Kresak) is fading this month from +7.7 to +11.0 by months end. It starts the month in Hercules and passes into Lyra on the 2nd. It passes through Lyra and then back into Hercules on the 16th for the remainder of the month. Click here for and ephemeris.

Noctilucent Clouds

Noctilucent Clouds may become visible towards the end of the month. These mysterious night time glowing clouds appear in the northern skies ans usually last between May to August. These clouds are very high at an altitude of around 90km. They are best seen around local midnight, looking due north. However, when a very active display is happening, they can be seen from sunset to sunrise.


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
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.