05-07-2008 July Night Sky (Article 144)

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Simon Kenny
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Location: Shannon, Co. Clare, Ireland

05-07-2008 July Night Sky (Article 144)

Post by Simon Kenny » Wed Dec 31, 2008 10:30 am

July Night Sky (Article 144)

July is the last month of the summer and you might notice that the evenings are starting to shorten by the end of the month, with sunset on July 1st at 9.56pm and 9.23pm by the end of July. At the start of this month, Mars and Saturn will pass very near each other in the sky. On the 6th, Mars and Saturn will be only 2 degrees apart (4 full moons) and will form a straight line with the primary star in Leo, namely Regulus. A thin crescent moon will be visible to the lower left of this trio making for a nice view in the sky. It will be placed in the lower western sky following sunset at 11pm.
By the 10th, Mars and Saturn will be at their closest, separated by only two thirds of a degree (less then 1.5 moon diameters), the problem here is that they are getting nearer to the Sun so will be even closer to the horizon (approx 6.5 degrees) by 11pm, trying to find them earlier than this might be difficult as the sky brightness tends to overpower their light but they should be visible to some extent from 10.15 onwards.
Using binoculars will help in seeing them, as always please wait until the Sun is fully below the horizon or you risk permanently destroying your eyesight if you accidentally pan your binoculars near the Sun.
Jupiter is visible in the far southern sky, its best seen at 2am at the start of the month and midnight at the end of the month. Its low altitude in the sky means you need a good unobstructed southern horizon to see it.
Uranus and Neptune are in the constellations Aquarius and Capricorn and are best seen between 2 and 3 am in the southern skies, a telescope is needed to see these, as well as detailed star maps.
The plough is commonly thought of as a constellation, it is in fact the brightest part of a constellation called Ursa Major (The great bear), this constellation can be seen this time of the year skimming along the northern horizon below the northern star, Polaris.
An easy way of finding the northern star is to locate the 2 most right hand starts of the plough and continue up a line these two stars make and you’ll come across Polaris, Many people think that Polaris is the brightest star in the sky, it is in fact the forty seventh brightest star in the sky making it unimpressive and not one that would stand out to a casual observer. Polaris never moves like other stars seem to do, it appears to be stationary as it is in a position that coincides with the Earths north pole, from the arctic it is seen as directly overhead, from the equator it is seen as been right on the northern horizon.

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