SkyEye

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

May 2012

The Calendar

All times and dates are given in Universal Time (UT).
Nightly darkness estimates are calculated for 45° N and 30° S.
Like total solar eclipses, lunar occultation events can be seen only from limited regions on Earth (and sometimes not at all if the occultation takes place during daylight hours). However, the Moon will appear close in the sky to its 'target' for some hours either side of the actual occultation, regardless of where you are.

Date		Event
1	Tue
2	Wed
3	Thu
4	Fri
5	Sat	Bright moonlight obliterates the Eta Aquariids.
6	Sun	Full Moon at perigee: not only is this the closest perigee of the year but it happens almost simultaneously with the Full phase; expect extremely high tides.
7	Mon
8	Tue
9	Wed
10	Thu
11	Fri
12	Sat	Last Quarter Moon
13	Sun	Jupiter at conjunction
14	Mon
15	Tue
16	Wed
17	Thu
18	Fri
19	Sat	Moon at apogee
19	Sat	3 Juno at opposition
20	Sun	The New Moon will partially obscure the disc of the Sun during an annular eclipse.
21	Mon
22	Tue
23	Wed	Neptune at west quadrature
24	Thu
25	Fri
26	Sat
27	Sun	Merucry at superior conjunction
28	Mon	First Quarter Moon
29	Tue
30	Wed
31	Thu

Coming up next month...

Where there's a solar eclipse you'll find a lunar eclipse near by and indeed there is a partial lunar eclipse early next month.

The big astronomical event of the year occurs 5-6 June when Venus makes a very rare transit across the face of the Sun. The next such transit will not take place until 2117!

Solstice ushers in summer north of the equator and winter in the southern hemisphere.

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: Aries » Taurus
Mercury: Pisces » Aries » Taurus
Never very high above the eastern horizon for northern observers, those in the southern hemisphere continue to enjoy very good pre-sunrise views of this elusive planet. It vanishes in the solar glare by the end of the month.
Venus: Taurus
The 'evening star' is getting increasingly difficult to see as it dives towards the Sun and a rare transit next month.
Mars: Leo
Well placed for evening observing, Mars does not set until after midnight.
3 Juno: Ophiuchus » Serpens
Tenth-magnitude asteroid 3 Juno reaches opposition on 19 May but a small telescope is necessary to see it.
Jupiter: Aries » Taurus
Jupiter is at conjunction on 13 May and thus, is too close to the Sun to be visible this month.
Saturn: Virgo
At opposition last month, the ringed planet is visible for most of the night, setting at dawn.
Uranus: Pisces » Cetus
The most distant planet that can be seen with the naked eye rises early in the morning, about an hour after Mars sets.
Neptune: Aquarius
A small telescope is necessary to view the most distant planet in the solar system. It reach west quadrature on 23 May and rises just after midnight.

The Celestial Sphere

Constellations are patterns of stars in the sky. The International Astronomical Union (IAU) 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 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

For More Information...

Consult our online glossary for non-technical explanations of many of the astronomical terms used in these pages.
Blue moons, eclipses, the dates of Easter and much more can be found at the Interactive Astronomy Pages.
For more information about the objects and events described in SkyEye, visit these astronomy-related sites.

Credits

Much of this information can be found in this month's issue of your favourite amateur astronomy magazine available in your local bookshop. Another excellent source is the current edition of the Astronomical Calendar by Guy Ottewell and published by the Universal Workshop.

The SkyEye banner features the supernova remnant known as the Crab Nebula. Six light years wide and 6500 light years distant, this expanding nebula is the shattered remains of a star that blew up nearly a thousand years ago. At its heart beats a pulsar, a neutron star which spins at the incredible rate of 30 times per second. The supernova explosion which produced this object was observed in 1054 in China, Japan and Arabia. It was also seen in North America by the Anasazi people who lived in what is now New Mexico and who depicted it in a petroglpyh. This image is a composite assembled from 24 individual exposures taken by the Hubble Space Telescope in October 1999, January 2000 and December 2000, and is courtesy of NASA, ESA, Jeff Hester and Allison Loll (Arizona State University). The colours represent different elements which were expelled during the explosion: neutral oxygen (blue), doubly-ionised oxygen (red) and singly-ionised sulphur (green). These elements will find their way into the next generation of stars and planets (and extra-terrestrial life?).