Image 1 Caption: "Christoph Scheiner (1573--1650) and a fellow Jesuit Catholic clerical scientist trace sunspots in Rome, Italy in about 1625." (Slightly edited.)

Features:

1. Christoph Scheiner (1573--1650) was one of pioneers of the helioscope or camera obscura telescope (which makes use of pinhole projections and a telescope) in order to do visual astronomy of the Sun without eye damage.

2. Sunspots had been observed since before 800 BCE in China, but they were still generally unknown in Europe at the dawn of the early telescopic era (1608--1700) in 1608 (see Wikipedia: Sunspot: History; Wikipedia: History of the telescope: Invention).

   Early observations may have been by looking at the Sun through clouds and/or at sunrise/sunset. Such observations will have caused eye damage. It is NOT clear from Wikipedia when camera obscura (a darkened room with aperture for pinhole projection) was first used to observe sunspots. Johannes Kepler (1571--1630) used it in 1607 just before the early telescopic era (1608--1700) (see Galileo Project: Science: Sunspots: scroll down ∼ 20 %).

3. The first telescopic discovery of sunspots was in 1610 December by Thomas Harriot (c.1560--1621) and then there was a second independent discovery in 1611 March by Johannes Fabricius (1587--1616) and his father David Fabricius (1564--1617). However, Harriot's discovery was NOT reported ????? in the early telescopic era (1608--1700) and Johannes Fabricius' publication of this discovery in 22-page pamphlet De Maculis in Sole observatis (1611) was NOT widely even at his death in 1616. So the widely known independent discoveries by Christoph Scheiner (1573--1650) (reported in Christoph Scheiner (1573--1650), De Maculis solaribus et stellis circa Iovis errantibus accuratior Disquisitio (1612)) and Galileo (1564--1642) (reported in Gallieo (1564--1642), Three Letters on Sunspots, 1612) achieved more recognition before 1616 (see Wikipedia: Sunspot: History).

   Apparently, some of these early observations of sunspots were done in looking at the Sun through the telescope, but with old way of looking through clouds or at sunrise/sunset since Benedetto Castelli (1578--1643) seems to have invented pinhole projection with a telescope only in 1612 (see Galileo Project: Science: Sunspots: scroll down ∼ 40 %).

4. Image 2 Caption: Observations of sunspots in 1612 by Christoph Scheiner (1573--1650) reported in Christoph Scheiner (1573--1650), De Maculis solaribus et stellis circa Iovis errantibus accuratior Disquisitio (1612).

5. For sunspots as they would have been seen, more or less, by the early telescopic era astronomers (1608--1700) see figure below (local link / general link: sun_white_light.html).

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6. Image 3 Caption: "The graph shows the sunspot counts since the early telescopic era (1608--1700)." The sunspot count varies approximately periodically with solar cycle (11 years on average; 9 to 14 year range). For more information, see Sun file: sunspots_solar_cycle.html.

7. See also Sun keywords below (local link / general link: keywords_sun.html):

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8. Solar atmosphere videos below (local link / general link: solar_atmosphere_videos.html):
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Images:

1. Credit/Permission: Christoph Scheiner (1573--1650), anonymous engraver in Rosa Ursina sive Sol (1626--1630) (uploaded to Wikimedia Commons by User:Rob at Houghton, 2014) / Public domain.
   Image link: Wikimedia Commons: File:Scheiner Viewing Sunspots 1625 - uncropped.jpg.
   
2. Credit/Permission: Christoph Scheiner (1573--1650), engraver Alexander Mair (1559--1617) in De Maculis solaribus et stellis circa Iovis errantibus accuratior Disquisitio (1612) (uploaded to Wikimedia Commons by User:Mr.saturn12, 2018) / Public domain.
   Image link: Wikimedia Commons: File:Scheiner plate observation (3).png.
   
3. Credit/Permission: © Robert A. Rohde (AKA User:Dragons flight), 2013 / Creative Commons CC BY-SA 3.0.
   Image link: Wikimedia Commons: File:Sunspot Numbers.png.
   

Local file: local link: sunspots_history.html.
File: Sun file: sunspots_history.html.

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