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


26th at 12.16h

First Quarter
3rd at 18.39h

11th at 06.08h

Last Quarter
19th at 09.19

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Note: All times quoted 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 2189 starts on the 2nd at 08h49m51s. Rotation number 2190 starts on 29th at 15h08m39s.


Is in the evening sky, low in the west soon after sunset. It is at greatest eastern elongation on the 1
st when it will be 19° to the left of the sun. It will be as bright as magnitude -0.2 on this date and will fade in magnitude as it moves nearer the sun. It passes through inferior conjunction (near side of the sun) on the 20th and moves into dawn skies. As seen through a telescope, Mercury will show a phase of 43% illuminated on the 1st and will shrink in phase illuminated as it draws ever closer to the sun. Its apparent disc size will increase from 7.5 arc seconds on the 1st to 11.8 arc seconds by time of inferior conjunction.


Will be found in the morning sky before sunrise, over in the east. It starts the month at magnitude -4.2 and will show a phase of 2.4% illuminated and apparent disc size of 57.9 arc seconds. As it draws away from the sun. its magnitude will increase to -4.7 and its phase will increase to 27.8% and disc size of 38.5 arc seconds by the 30
th .


Is a post sunset object in the west, shining at magnitude +1.5 to +1.6. It is in the constellation Aries until the 12
th when it will move into Taurus. On the 1st, Mars can be used as a guide to find Mercury which will be 15° to the lower right of Mars.

A challenge observation will be seeing the thin crescent Moon (8.3% illuminated) 9° to the left of Mars low in the west in the evening twilight sky on the 28th. The bright star Aldebaran will be seen to the lower right of the Moon at this time as well.


Comes to opposition on the 7
th at 22 hours when it will be seen opposite the sun in the sky. On this date, the planet will be seen rising in the east (18.48h) and be shining at magnitude -2.5
The planet will be visible all night and set at 05.57h on the 8
th. The planet will be at a distance 4.5AU (414 million miles) The very near Full Moon will be seen above Jupiter on the evening of the 10th and should be a lovely naked sight.

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.


Is in the constellation Sagittarius shining at magnitude +0.4 to +0.3 and will rise at 01.38h on the 1st and at 23.38h on the 30th. The rings are well presented towards earth at an angle of around 26° On the morning of the of the 16th , the waning gibbous moon will join Saturn and form a triangular pattern with the red star Antares in Scorpius.

The brightest moon of Saturn, Titan will be seen west of the planet on 1st ,2nd ,3rd ,17th ,18th and 19th .It will be east of the planet on 8th ,9th ,10th ,11th ,24th ,25th ,26th and 27th .Titan will require a telescope to see as it will be faint at magnitude +8.6.


Virginid meteors are active during the month with maximum activity during 11th and 12th. The rate is low at on 5 meteors per hour (ZHR). The meteors move in long, slow paths across the sky. Radiants at RA14h04m Dec. -09° and RA13h36m Dec. -11°

Lyrids are active from 18
th to 25th with a maximum on the 22nd. Rates are 10 meteors per hour (ZHR). Fine displays were seen in 1803, 1922 and 1982 so it will be worth while observing this year in case of enhanced activity. Radiant at RA18h08m Dec.+33°
The meteors from the shower originate from comet Thatcher that was discovered in 1861 by A. E. Thatcher.

alpha-Scorpiids are active from 20th and into May with two peaks in activity. One on the 28th April and the other on the 12th May. Rates are low at only 5 meteors per hour (ZHR). Radiant at RA16h31m Dec. -24°

eta-Aquarids are active from the 24th with a maximum due in May. Radiant at RA22h30m Dec. -01°

(Stars Brighter than Magnitude +6.0)

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

13th    23.35:10      2223      159370         +3.9           096° DD             gamma Libra D*
19th    04.28:13      2902      163060         +5.9           216° RD             57 Sgr D*
28th    18.06:51      692        94027           +0.1          056° DD             Aldebaran D* Daylight
28th    18.00:38      692        94027           +0.1          292° RB             Aldebaran D* Daylight

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

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 C/2015 V2 (Johnson) will be in Hercules all month, shining at magnitude +8.4 on the first and brightens to +7.4 by the end of the month. Click here for an ephemeris.

Comet P/Tuttle-Giacobini-Kresak (41P) is racing across the skies this month. It will be found in Draco at the start of the month at magnitude +6.7. It will move into Hercules by the 20th and will have faded to magnitude +6.9. By the end of the month, it will have faded to +7.7. Click here for an ephemeris.


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.