SkyEye

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

February 2011

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	New Moon
4	Fri	Mars at conjunction
5	Sat
6	Sun	Moon at apogee
7	Mon
8	Tue	The waxing crescent Moon sets early enough to not interfere with observations of the Alpha Centaurids (theoretical peak activity: from 12:00 UT).
9	Wed
10	Thu
11	Fri	First Quarter Moon
12	Sat
13	Sun
14	Mon
15	Tue
16	Wed
17	Thu	Neptune at conjunction
18	Fri	Full Moon
19	Sat	Moon at perigee
20	Sun
21	Mon
22	Tue
23	Wed
24	Thu	Last Quarter Moon
25	Fri	Mercury at superior conjunction
26	Sat
27	Sun
28	Mon

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: Capricornus » Aquarius
Mercury: Sagittarius » Capricornus » Aquarius
The nearest planet to the Sun disappears from the morning sky early in the month for northern hemisphere observers. However, viewers in southern latitudes can see Mercury for the first half of the month before it gets lost in the solar glare on its way to superior conjunction on 25 February.
Venus: Sagittarius
For southern observers, the "morning star" continues to climb higher in the eastern sky during the first half of the month. Northerners see this bright planet gliding gently towards the sunrise horizon throughout the month of February.
Mars: Capricornus » Aquarius
The red planet is at conjunction on 4 February so it is not visible this month.
Jupiter: Pisces
Look for the largest planet in the solar system in western skies at sunset.
Saturn: Virgo
The ringed planet rises mid-evening, about an hour after its neighbour, Jupiter, sets.
Uranus: Pisces
This distant gas giant has not wandered far from its brighter outer solar system companion, Jupiter, since their conjunction last month.
Neptune: Aquarius
A small telescope is usually necessary to view the most distant planet in the solar system but observations are impossible this month because Neptune is at conjunction on 17 February.

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 beautiful planetary nebula NGC 2818. A planetary nebula is a glowing shell of gas surrounding a dying star. When a star begins to run out of fuel and expands into a red giant, the outer layers of the star are expelled into space, enriching the surrounding area with the heavy elements manufactured by the parent star. The remaining hot stellar core ionises the ejecta, causing it to glow for a few tens of thousands of years. Eventually the star fades away and nebula is no longer visible. This image was taken by the Hubble Space Telescope in November 2008 and is courtesy NASA, ESA, and the Hubble Heritage Team (STScI/AURA). The red colour represents nitrogen, green represents hydrogen and blue represents oxygen.