Sun and sunspots in 1910s, stereoscopic card. These are paired stereoscopic images which provide a 3D image (stereogram) when viewed side-by-side. Sunspots (dark areas) are areas of magnetic activity that are cooler than the rest of the Sun's surface. Image obtained with the 40-inch refracting telescope at the Yerkes Observatory, Chicago, USA. Published by the Keystone View Company. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / US Naval Observatory |
Bildgröße: | 4176 px × 2126 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |