This month contains the longest day and therefore the shortest night. This means that in order for hardy astronomical souls to be looking at the night sky we are talking about staying up until the early hours of the morning to catch a glimpse of the heavens

PICTURE COURTESY OF SOHO

This month contains the longest day and therefore the shortest night. This means that in order for hardy astronomical souls to be looking at the night sky we are talking about staying up until the early hours of the morning to catch a glimpse of the heavens. Even then the sky does not get truly dark, therefore this month we shall be studying our nearest star, the Sun.

Within our Galaxy the Sun appears to be a rather ordinary yellow star, but we have had over the last few years a number of telescopes and other instruments looking at how it all works. The sun is a large and massive ball of energy, generated from the nuclear reactions within its core. The sun is an important source of heat and light, necessary for the continuation of life on the Earth. It can also be harmful and needs to be monitored.

The SOHO project (Solar and Heliospheric Observatory) consists of an orbiting space telescope which looks at the sun's solar activity, primarily for solar weather prediction. They are looking for flares which could damage space craft, satellites and power grids on earth. Major solar activity can also cause climate changes on our small planet, so it is an important field of research.

The above image is courtesy of SOHO and is a combination of images taken at three wavelengths in ultraviolet which reveals details in the Sun's corona not normally seen.

Other space observatories are TRACE (Transition Region and Coronal Explorer) which looks at the Solar Corona, HESSI (High Energy Solar Spectroscopic Imager) which looks at the sun in X ray and Gamma ray and POLAR which is measuring the solar wind activity and strength of the magnetic and electric fields using multi-wave imaging.

The image above is courtesy of TRACE. This image taken in ultraviolet reveals ionised gas trapped by the intricate magnetic fields that extend out of the Sun’s photosphere.

There are many ground based observatories looking at the Sun, but as amateur astronomers, we can safely look at solar activity using a cardboard box, a piece of card and a pair of binoculars or a small refracting telescope. This is called solar projection, and we can easily see sun spots using this technique. Sunspots are cooler areas on the sun’s surface which appear to be dark, but are actually very bright. By projecting the sun’s image onto a piece of card, we can see these

spots” and can, over time, log their progress across the surface of the sun. In ancient times people noticed sun spot activity, and in the nineteenth century records of the phenomena were recorded daily.

PLEASE REMEMBER - DO NOT LOOK DIRECTLY AT THE SUN WITH THE NAKED EYE OR THROUGH BINOCULARS OR A TELESCOPE AS THIS WILL SERIOUSLY DAMAGE YOUR EYES.

Using a special solar telescope, known as a Hydrogen Alpha Telescope, we can view the Chromosphere of the sun, seeing solar flares, filaments, prominences and a very beautiful red coloured sun. This type of telescope looks at the suns surface within the Hydrogen Alpha wave band of light. The sun appears to be red because the hydrogen atoms are excited by the high temperatures (ranging from 6000° Kelvin to 50,000° Kelvin), and emit radiation within the red part of the visible spectrum.

On Saturday 27th June the North Devon Astronomical Society will be holding a special Solar Event at the Sportsman Inn, Sandyway, Exmoor from 2pm and you will be able to view the sun through one of these Hydrogen Alpha Telescopes. Please come along and have fun. Everyone is welcome.

THE PLANETS

MERCURYNot seen in the sky this month

VENUSLow in the Eastern morning sky

MARSVery low in the Eastern morning sky

JUPITERIn the Southern morning sky

SATURNIn the evening Western sky

MOON

FULL7th June

3rd QUARTER14th June

NEW MOON22nd June

1st QUARTER29th June

Report by Julie Buckingham, Secretary North Devon Astronomical Society