31-01-2009 February Night Sky (Article 172)

[Simon Kenny]

February Night Sky (Article172)

With January now behind us, the 1st of February marks the beginning of Spring. Twilight noticeably stretches into the evening. Sunset at the start of the month is at 5.20pm while at the end of the month sunset is at 6.12pm, sunrise is at 8.16am on the 1st and 7.23am on the 28th.
The planet Venus has been visible for the past few months in the west after sunset, this month is no exception. It is visible between 6 and 8pm throughout the month as a dazzling bright star. When viewed through a telescope, at the start of the month, it will present a half moon phase; this will change rapidly and by the end of the month it will have a crescent shape when viewed through a telescope. This month is the last time it will be easily visible this year in the evening, as in March it will plunge towards the Sun - as seen from Earth.
The planets Mercury, Mars and Jupiter are not visible this month as they are too near the Sun as seen from Earth. Saturn is visible from 11pm in the east and will be rising earlier as the month goes on - it is located in the constellation Leo. Through a telescope you will see that its rings are nearly edge on but they will be widening as the month goes by making them easier to see. With a telescope and some luck you might witness one if its many moons transiting across the disk of the planet, following that you might see the shadow cast by the moon as a tiny dark dot on the disk of the planet.
The Moon is at first quarter on February 2nd and is best visible in the early night. Full moon is on the 9th and is best seen towards midnight. Last quarter is on the 16th and is best seen in the hours before sunrise low in the southern sky and new moon is on the 25th.
Winter constellations such as Orion and Taurus, which were high in the sky throughout the December and January, are now setting at midnight and the Spring constellations are in the ascendancy, constellations such as Cancer and Leo. Ursa Major (which contains the plough) is almost overhead for a lot of the month late into the night.
This month’s club meeting is the AGM, it will be held in Mary Immaculate College Limerick at 8pm on Wednesday the 4th. We would encourage all club members to attend, as the election of the club positions will be held. New members are also welcome.