The Night Sky in March 2006

Looking at the night sky with the naked eye or using a small telescope can be fascinating, so each month these notes keep you up-to-date with unfolding events.

Maps of the current night sky can be seen by clicking HERE

Phases of the Moon

New Moon Wednesday 29	First quarter Tuesday 7	Full Moon Tuesday 14	Last quarter Wednesday 22

Click HERE to see the phase of the Moon on each day of the month.

 

Monthly Highlights

With the days getting longer, we are starting to see the first signs of spring as daffodils pop up all over the place. Another major milestone in the changing seasons will be the spring equinox on the 20th March, when the UK will receive the same amount of daylight and darkness i.e. 12 hours of each. Thankfully, there is still enough darkness to get a good look at the night sky without staying up too late, and hopefully, we may spot one of the following monthly highlights:

March 20th - Spring Equinox

On the 20th March (21st March in some years), at precisely 6:26 pm, the Sun will cross over the Earth's equator to be above the Northern Hemisphere. This moment is known in the UK as the spring or vernal equinox, whereas in the Southern Hemisphere, this point is known as the autumnal equinox.

The spring equinox has been celebrated for thousands of years throughout the British Isles, and indeed the whole Northern Hemisphere, because it signifies the transition from spring toward Summer and with the warmer, longer days comes the renewal of life in our woodlands and fields, which has been so vital to our very survival.

Image showing how the Earth's orbit changes through the year to give our seasons

Translated literally, equinox means "equal night". Because the Sun is positioned above the equator during the equinox, day and night are about equal length all over the world. A second equinox will occur on the 23rd September, when the Sun returns to the Southern Hemisphere and signals the approach of winter for the UK, and Summer for countries in the Southern Hemisphere, such as Australia, Chile and South Africa.

If you want to learn more about the seasons, follow this link.

March 29th - Partial Solar Eclipse

Early on the morning of the 29th March there will a total eclipse of the Sun visible across parts of West and North Africa, Turkey, and Southern Russia. An eclipse occurs where the Moon passes in front of the Sun and blocks out some or all of the sunlight, causing it to go dark for a few minutes. In other words, we pass through the shadow of the Moon. As you can see in the animation, the actual point of total eclipse (dark spot) is very small and travels fast, so people in the eclipse path will only lose sight of the Sun for a few minutes at most.

Animation showing the path of the solar eclipse on the 29th March 2006

From the UK we will only be able to see a partial eclipse of the Sun because we do not lie directly beneath the Moon's path. In fact no more than 12% of the Sun's light will be blocked out. Remember, you should never look directly at the Sun because it can easily damage your eyes. If you want to view eclipses, you need special glasses and equipment - ask your teacher for more details. If the weather stays clear and you want see the eclipse then you will need to bear in mind the following times -

First Contact (when the Moon first starts to cover the Sun)

London         09:45

Manchester   09:49

Edinburgh     09:55

Last Contact (when the Moon stops covering the Sun)

London         11:22

Manchester   11:18

Edinburgh     11:17

The Planets

Click HERE and start the Electric Orrery to see where all the planets are today in relation to each other.

Mercury Mercury starts the month as a steady evening star, making an hour long appearance after the Sun goes down. The planet is currently circling around to pass in front of the Sun. It will reach inferior conjunction (between us and the Sun) on the 12th March, and will therefore be lost in the Sun's glare around that time. It will re-appear towards the end of the month as a morning object, visible just before the Sun comes up. Unfortunately, because Mercury is always low when the Sun is about, it is one of those objects that the Liverpool telescope cannot safely observe. Venus Venus continues to overtake us on the inside after passing infront of the Sun at the end of January. Early birds can spot the brightest planet at 4.30am toward the east-southeast around 2 hours before sunrise. During the month Venus increases its angular separation from the Sun, getting brighter as it does. It will reach maximum separation during May, which will be our best opportunity to see it - if we are prepared to get up that early that is. Why not use the electric orrery to watch how Venus increases its angular separation over the next couple of months. Mars Mars remains prominent throughout the month but continues to diminish in size and brightness as Earth moves away. It can be found high above the southern horizon shortly after sunset and spends half the night crossing the sky until it sets in the west-northwest around 1am. This moves back to midnight by the end of the month as we continue to move away. We can still observe Mars using the Liverpool telescope, but sadly it will be another 18 months before we get really detailed images again. Jupiter Jupiter is slowly becoming the planet of the moment as we gradually catch it up on our inside orbit or track. It continues to increase in size and brightness, and at the start of March it can be found rising in the east-southeast around 11.30 in the evening. By sunrise it will have made its way to a position low above the southwestern horizon. Jupiter remains the second brightest planet (after Venus) and will shortly be overtaking Saturn as the best target to observe. Why not use Go Observing to obtain an image of Jupiter and see if you can capture its elusive red spot. Saturn Saturn remains the best target to observe at the moment, although it's starting to decrease in both size and brightness as we move slowly away. Come the middle of March, Saturn will be found high to the east-southeast shortly after sunset and spends the night crossing the sky before finally setting in the west-northwest around 3.30 in the morning If you act fast in requesting an observation, you could still bag a decent picture of Saturn, although your chances are growing less as the month moves on. Hopefully any images should still show weather features on the surface of the gas giant and even detailed structure in Saturn's ring systems.   Constellation of the month Each month, new constellations are highlighted for you to identify in the night sky. This month we will be looking for the winter constellation of Gemini, the Twins. For those of you who know a little bit of astrology, you may think of Gemini in terms of people who are born in the Summer. However, signs of the zodiac relate to the constellation that the Sun is going through at any particular moment. Since Gemini is a mid-Summer sign of the zodiac, that means in the winter we will see it in the other direction to the Sun i.e. at night time. Gemini is quite easy to find on a clear night because it currently lies between the planets of Saturn and Mars, both of which are easy to pick out as they appear as bright, steady (not twinkling) points of light. March Night Sky The Greeks named the constellation's brightest two stars Castor and Pollux, after the mythological twins - more about that later. Castor and Pollux make up the heads of the twins, and can be seen in both images just above and to the right of Saturn. You can tell that the Sun must pass through Gemini at some point because Saturn has just done so and Mars is about to. Remember, the Sun and planets (apart from Pluto) lie on the same plane and therefore follow the same path through the night sky. This path is known as the ecliptic (see below) and you can be certain that the Sun, planets and Moon will never be far from it. Path of the Solar System Image showing the Ecliptic path that the Sun, planets and Moon follow  © Stellarium Because the Earth is tilted by 23.5 degrees to the ecliptic, we find that during the year the position of the ecliptic will move around in the opposite way to the Sun, in the sense that the ecliptic will be higher at midnight in the Winter than in the Summer. Mythology: Gemini Gemini is a zodiacal constellation representing the twin brothers Castor and Pollux. Both were mothered by Leda, and were therefore brothers of Helen, but they had different fathers: In one night, Leda was made pregnant both by Jupiter in the form of a swan and by her husband, the king Tyndarus of Sparta. Pollux, as the son of a god, was immortal and was renowned for his strength, while his mortal brother Castor was famous for his skill with horses. Both brothers voyaged in search of the Golden Fleece as Argonauts, and then fought in the Trojan War to bring their sister home to her husband Menelaus. They are traditionally depicted as armed with spears and riding a matched pair of snow-white horses. The most common explanation for their presence in the heavens is that Pollux was overcome with sorrow when his mortal brother died, and begged Jupiter to allow him to share his immortality. Jupiter, acknowledging the heroism of both brothers, consented and reunited the pair in the heavens.