Sun Gallery


Introduction

The Sun is our nearest star, vital to the wellbeing of the Earth but is nothing special on the galactic scale of things. It is termed a yellow dwarf, and is situated in one of the outer spiral arms of the MIlky Way galaxy.

It is so bright for us that precautions should be taken at all times when attempting to view it - please see here for what is and is not safe.

My observations of it have mainly been confined to when it is eclipsed by the Moon - see the Solar Eclipse pages for details. However, since obtaining two filters for my small Helios telescope in 2003, a white light filter and a Hydrogen Alpha filter (see here for details) it has been possible to safely view and photograph the Sun at other times, and I hope to add to a gallery of interesting pictures over time.

Very occasionally, rarer even than a total eclipse, the planet Mercury or Venus may pass betwen the Earth and the Sun and be sihouetted against it. Please see the Mercury page for pictures of such an event in May 2003 and hopefully I will have something to report in June 2004 for an even rarer transit of Venus.

Apart from eclipses the Sun appears fairly unchanging but is really a turbulent body of great violence fuelled by nuclear fusion. This manifests itself in the form of sunspots - slightly cooler areas of intense magnetic disturbance, and flares (more properly called Coronal Mass Ejections these days). If CMEs are directed towards the Earth they can cause beautiful auroras and more seriously, electrical and radio blackouts in high latitudes and danger to satellites and people in space.

The Sun's magnetic field reverses back and forth in a 22 year cycle, which results in a waxing and waning of sunspot and CME activity on an 11 year cycle. Auroras therefore follow a similar pattern, becoming more intense and common in lower latitudes (e.g. in Britain) around the time of solar maximum. 1991 and 2002 fitted into this pattern, and the next will be in 2013.

Sun Fact File

Distance from Earth (Million km): 147 (min) 152 (max)
Diameter (km): 1,392,530
Rotation Period: 25d 9h 7m
Apparent Diameter (arc minutes & seconds): 32m 35s (max), 31m 31s (min)
Max. Apparent Brightness (magnitude): -26.8


Sun Storm, 25 - 30 Oct 2003

 


External Links...

NOAA Space Environment Centre for up to the minute data and the effect on the Earth
ESA / NASA SOHO for fine pictures and movies of solar activity

 

Planets Home Mercury


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