May 2017

Welcome to SkyEye, your guide to this month's celestial events.

The Calendar

Date Event
Monday 1
Tuesday 2
Wednesday 3 First Quarter Moon
Thursday 4 Moon occults the first magnitude star Regulus: visible from Australia, New Zealand beginning around 09:15 UT.
Friday 5
Saturday 6 The waxing gibbous Moon should not unduly hamper observations of the Eta Aquariid meteor shower. Best observed from equatorial and southern regions, the predicted peak of this shower is around 02:00 UT.
Sunday 7
Monday 8
Tuesday 9
Wednesday 10 Full Moon
Thursday 11
Friday 12 Moon at apogee
Saturday 13
Sunday 14
Monday 15
Tuesday 16
Wednesday 17 Mercury at greatest elongation west
Thursday 18
Friday 19 Last Quarter Moon
Saturday 20 Moon occults Neptune: visible from the south Atlantic beginning around 05:30 UT.
Sunday 21
Monday 22
Tuesday 23
Wednesday 24
Thursday 25 New Moon
Friday 26 Moon at perigee less than six hours after new phase: expect unusually extreme tides.
Saturday 27
Sunday 28
Monday 29
Tuesday 30
Wednesday 31 Moon occults the first magnitude star Regulus: visible from central and southern Africa (except southern tip), Madagascar beginning around 15:30 UT.

The Solar System

The word planet is derived from the Greek word for 'wanderer'. Unlike the background stars, planets seem to move around the sky, keeping mostly to a narrow track called the ecliptic, the path of the Sun across the stars. Dwarf planets and small solar-system bodies, including comets, are not so constrained, often moving far above or below the ecliptic.

Sun AriesTaurus

Mercury PiscesCetusAries

The closest planet to the Sun is particularly well-placed for observing in the morning sky from the southern hemisphere. It reaches greatest elongation west on 17 May.

Venus Pisces

The morning star climbs high above the eastern horizon for southern hemisphere observers and becomes easier to see for those in the north as well.

Mars Taurus

Mars is setting ever earlier as it heads towards solar conjunction this summer. Compare its colour to that of the bright star Aldebaran when the red planet passes close by on 7 May.

Jupiter Virgo

Since it doesn't set until after midnight, the largest of the planets is easy to observe during the evening hours.

Saturn SagittariusOphiuchus

Now rising well before midnight, the ringed planet is more convenient to observe during the evening.

Uranus Pisces

This faint ice giant may still be too close to the Sun to be seen in the morning sky this month.

Neptune Aquarius

A small telescope is necessary to view the most distant planet in the solar system. Neptune rises in the early morning hours and is occulted by the Moon on 20 May.

The Celestial Sphere

Constellations are patterns of stars in the sky. The International Astronomical Union recognises 88 different constellations. The brightest stars as seen from the Earth are easy to spot but do you know their proper names? With a set of binoculars you can look for fainter objects such as nebulae and galaxies and star clusters or some of the closest stars to the Sun.

Descriptions of the sky for observers in both the northern and southern hemispheres are available for the following times this month. Subtract one hour from your local time if summer (daylight savings) time is in effect.

Local Time Northern Hemisphere Southern Hemisphere
1730 hours (1830 hours summer time) 45° N 30° S
1930 hours (2030 hours summer time) 45° N 30° S
2130 hours (2230 hours summer time) 45° N 30° S
2330 hours (0030 hours summer time) 45° N 30° S
0130 hours (0230 hours summer time) 45° N 30° S
0330 hours (0430 hours summer time) 45° N 30° S
0530 hours (0630 hours summer time) 45° N 30° S