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Observing the Sun is potentially very dangerous! The only two safe methods are projection onto a screen or use of a special filter that covers the front end of the telescope.


White light features...

Sunspots are cooler regions (4200K) that appear dark in contrast to their hotter (5800K) surroundings. They are caused by strong magnetic fields (up to 0.4T) that prevent hot gases from deeper inside the Sun rising upwards. Normally, convection would supply fresh hot gas, but in sunspots the lack of replenishment allows cooling to take place.
The number of sunspots varies greatly from day to day and shows a roughly 11 year cycle of activity. Sunspot activity is linked to auroral displays.

Faculae are often associated with sunspot groups and appear as a network of brighter material, only seen when near the limb where contrast is greater. They are hotter regions and appear before a sunspot emerges from the photosphere and last after the spot has disappeared.


H-alpha features...

H-alpha images from 2003 to mid-2005 were obtained with a SolarMax 40 Hydrogen Alpha filter supplied by Coronado with a band pass of less than 0.08nm. This was double stacked from the summer of 2005 onwards to produce a band pass of less than 0.05nm. The filter only transmits light with the exact wavelength of 656.3nm (corresponding to the H-alpha line in the Sun's spectrum). This has the desirable effect of dramatically increasing the contrast of  prominences ('flame-like' structures) and other features that originate in the chromosphere.

Solar flares are temporary brightenings caused by the reconnection of lines of opposite magnetic flux. They occur where the magnetic field is twisted into a complex pattern, with opposing polarities in close proximity.

Plages are much longer lived lesser brightenings often associated with sunspot groups.

Filaments are dark, worm-like features. They are simply prominences seen in front of the solar disk.

The images prior to 2003 were all obtained with a Lumicon 0.15nm band pass Hydrogen Alpha filter.