Manx skies... April
2017 ~ compiled by Dave Storey
times quoted are Universal Time (UT)
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
24 now in force.
NEVER DIRECTLY OBSERVE THE SUN WITH YOUR NAKED EYES AND/OR OPTICAL
INSTRUMENTATION: YOU WILL BE BLINDED!
Solar Rotation number 2189 starts on the 2nd at 08h49m51s.
Rotation number 2190 starts on 29th at 15h08m39s.
in the evening sky, low in the west soon after sunset. It is at
eastern elongation on the 1st
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
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 30th
a post sunset object in the west, shining at magnitude
+1.5 to +1.6. It is in the constellation Aries until the 12th
when it will move into Taurus. On
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
The bright star Aldebaran will be seen to the lower right of the
Moon at this time as well.
on the 7th
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
The planet will be visible all night and set at 05.57h on
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
and should be a lovely naked
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
To help you identify the moons
at any particular time, Sky
and Telescope have
tool that will plot the moon positions. Click
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
.It will be east of the planet on
.Titan will require a telescope
to see as it will be faint at magnitude
meteors are active during the month with maximum activity during
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°
are active from 18th
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
The meteors from the shower originate
from comet Thatcher that was discovered in 1861 by A. E. Thatcher.
are active from 20th
into May with two peaks in activity. One on the 28th
and the other on the 12th
Rates are low at only 5 meteors per hour (ZHR).
Radiant at RA16h31m Dec. -24°
are active from the 24th with a maximum due in May.
Radiant at RA22h30m Dec. -01°
Brighter than Magnitude +6.0)
Magnitude. P.A. Type of event. Notes
13th 23.35:10 2223 159370 +3.9 096° DD gamma
19th 04.28:13 2902 163060 +5.9 216° RD 57
28th 18.06:51 692 94027 +0.1 056° DD Aldebaran
28th 18.00:38 692 94027 +0.1 292° RB Aldebaran
very detailed list of occultations visible this month, Click
here. (Data from Occult Software)
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.
= 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
D* = Double Star
above predictions were calculated from Occult software by David
Herald. More information regarding this software may be found at
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.
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.
transit Information from Heavens Above.com
for Manx Night Skies
Handbook of the British Astronomical Association 2017. BAA.
Stargazing 2017. Heather Couper & Nigel Henbest.
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
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
2000.0 Edited Ian Ridpath. Longman Scientific & Technical.
Planetary data derived from
Picture graphics derived from Stellarium
and Guide 9 Software.