Naked Eye Sunspot

Provided and copyright by: Wojciech Rychlik
Summary authors & editors: Jim Foster; Wojciech Rychlik

The above photo of the setting Sun was made earlier this month near Cascade, Colorado. On April 9, sunspot number 330 was virtually the only sunspot visible on the face of the Sun. However, since it was quite large, you may have been able to see it without using a telescope or binoculars. To look for naked eye sunspots, observe at sunset when the Sun's rays are dimmed by a thicker atmosphere (greater pathlength). However, even when the Sun is close to the horizon, you should use a Sun filter or something similar so as not to damage your eyes.

Related Links:

• The Suspot Cycle
• Sunspot Numbers
• About Sunspots
• Atmospheric Optics
• Observing the Sun for Yourself

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