Saturday, July 28, 2007

Starry Splendour Over Prince Albert

- Hans Daehne -

In August the days will already become noticeably longer since they started to lengthen by one minute in the morning and one minute in the evening from the 7th of July.

This is the time for the rich winter constellation Sagittarius in the dense part of the Milky Way above our heads at night; but the Archer is difficult to recognize as a man’s trunk with bow and arrow and a lower body of a horse.

It is much easier to look for a teapot with lid, handle and spout under the Scorpion where the Milky Way seems to split. This is the direction of the centre of our Milky Way galaxy and in this area of the sky we can find at least 20 Messier objects i.e. open clusters, globular clusters, double stars and nebulae that are awesome through binoculars and telescope.

Near Sagittarius is a clear little arch of star, like a crown, hence its name: Corona Australis, the Southern Crown.

For naked eye observations just after sunset the grouping of bright Venus, Saturn and Regulus in Leo make a beautiful attraction during the first third of the month.

Venus will be at inferior conjunction with the Sun on the 18th of August that means she will be closest to Earth (43mil. km = 0,29 AU) but not visible to us. At the end of the month Venus will reappear as the striking Morning Star.

New Moon is on the 13th with Full Moon since the" Blue Moon" in June at the end of the month.

The Full Moon will also be at its closest approach to Earth (perigee) which is usually a more favourable configuration for rain in the Western Cape.

Jupiter in the east is opposite Venus and being very bright just after sunset helps to indicate the Ecliptic, the plane that the planets and the Moon describe around the Sun.

Saturn can only be observed for a short while after sunset at the beginning of August thereafter it will get too close to the Sun on its way to its conjunction with the Sun on the 21st of August.

Looking north a configuration like a large cross can be seen. This is Cygnus, the swan, thus also called the Northern Cross.

The Sun is our most observed star with six unmanned solar telescopes spread over the Earth, studying the Sun continuously. One of these automatic telescopes is at Sutherland where it tracks the Sun automatically and measures the oscillation of the Sun caused by the gravitational pull of the passing planets. There are also eight dedicated satellites keeping the sun if their focus to measure solar flares, sun spots and the ejection of solar energetic particles that cause beautiful Auroras in the polar regions but that are dangerous to Earthlings and especially astronauts. Never look at the Sun with unprotected eyes or through unsuitable equipment!

The beloved Southern Cross is now positioned on its side with the pointers above it, all of them on their way to disappear behind the Swartberg mountain soon until January but the outstanding Magellan Clouds high in the sky will make up for this.

Keep the stars in your eyes!

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