29-03-2008 April night sky (Article 130)

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Simon Kenny
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Location: Shannon, Co. Clare, Ireland

29-03-2008 April night sky (Article 130)

Post by Simon Kenny » Fri Jan 02, 2009 4:30 pm

April night sky (Article 130)

Once into April the evenings are getting noticeably brighter and at the beginning of the month it is about 9 pm when the sky is nicely dark and by 30th it is nearly 10 pm before the fainter objects become visible.

Let’s have a look at the usual suspects and start with the Moon. On 7th at 9 pm in WNW after sunset you should see a 2 day old waxing Moon with a mere 4% of its disc illuminated by the Sun. If you are used to noting the Moon’s position during its cycle you will have noticed that it gradually rises further east each evening. So, on 19th at 9 pm it will be in the SE sky about 17º above the horizon and still waxing gibbous with its disc just a tad short of being 100% illuminated by the Sun.

Where will the planets be during April? Well, Mercury and Venus will both be close to each other but they will lie very close to the horizon and more importantly they will be sitting too near to the rising Sun. We do not recommend trying to observe them during this month and would warn that instant blindness can occur if you look through binoculars or a telescope at the Sun. Mercury is the closest planet to the Sun and interestingly by the 25th it will have gone around the Sun and appear on the other side . This means that from our perspective it appears on the Sun’s left hand side, meaning that when the Sun sets at about 8 pm on the 25th, Mercury will still be in the evening sky about 10º above the horizon, but it is risky to try to observe it.

If you have a flat horizon, Jupiter rises about 3:30 am but very low on the horizon and by 15th it will be 9º above the SSE horizon in a brightening sky, again we warn of the Sun. Mars will look very ‘orangey’ in the SW sky and is easily spotted sitting high above the familiar three diagonal stars of Orion’s belt. It will be 53º above the horizon on 1st, 50º up on 10th in SW, dropping to 40º in WSW on 5th and on 30th it will be as low as 30º in W sky.

Do try to get a look at Saturn through even a small telescope and prepare to be ‘WOWED’. Try observing it at 10 pm through April. It will be well positioned for viewing. On 1st it will be 50º high almost due S. On 15th it will be just above a 10.5 day old waxing gibbous Moon and by 30th it will be 45 º high in a SSW sky.

For the folks with the big telescopes Uranus and Neptune are close to Mercury and Venus in the sky from Earth’s viewpoint and again too close to the Sun to try observing. Pluto, a tiny dot as it is, is 7º high in SE on 1st at 2:30 am. This increases to 10º on 10th, 12º on 15th, up to 17º by 30th.

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