This graph shows the number of sunspots seen each year. The graph covers 400 years, from 1600 to 2000. There were very few sunspots during the Maunder Minimum. The Dalton Minimum is another time when there were fewer sunspots than normal.
Click on image for full size
Image courtesy NASA (modified by Windows to the Universe staff).
History of Sunspot Observations
Humans have looked for and written down information about
sunspots for a very long time! In fact, the first time someone wrote down sunspot information was almost 3,000 years ago in China!
An English monk named John of Worcester made the first drawing of sunspots in 1128. Soon after the invention of the telescope, astronomers used the telescope to make observations of sunspots. This was around 1600.
Sunspot number across these many years has been linked to solar activity. Solar activity affects things on Earth in what we call "space
weather".
Sunpot number is also thought to be linked to climate. There is one famous time called the Maunder Minimum. It was from 1645 to 1715. There were not many sunspots found on the Sun during that time and there were really cold winters in Europe known as the Little
Ice Age. You can impress your teachers by telling them this though! Sunspot counts have
been higher than usual since around 1900, so some scientists
call
the time we are in now the Modern Maximum.
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