Kikkert (Danish Wikipedia)

Analysis of information sources in references of the Wikipedia article "Kikkert" in Danish language version.

refsWebsite

Global rank Danish rank

9rice.edu

3,843^rd place

3,831^st place

5stardate.org

low place

rice.edu

galileo.rice.edu

The Galileo Project – The telescope (Webside ikke længere tilgængelig), It consisted of a convex and concave lens in a tube, and the combination magnified three or four times.
The Galileo Project – The telescope (Webside ikke længere tilgængelig), With this instrument he observed the Moon, discovered four satellites of Jupiter... The next discovery, that of sunspots, was made by several observers, including Galileo, independently
The Galileo Project – The telescope (Webside ikke længere tilgængelig), It had a plano-convex objective (the lens toward the object) with a focal length of about 30-40 inches., and a plano-concave ocular with a focal length of about 2 inches... which meant that only a quarter of the full Moon could be accommodated in the field.
The Galileo Project – The telescope (Webside ikke længere tilgængelig), As early as 1611, in his Dioptrice, Johannes Kepler had shown that a telescope could also be made by combining a convex objective and a convex ocular... the addition of yet a third convex lens would make the image erect again.
The Galileo Project – The telescope (Webside ikke længere tilgængelig), In his study of sunspots, Scheiner had experimented with telescopes with convex oculars in order to make the image of the Sun projected through the telescope erect. ...although the image was inverted, it was much brighter and the field of view much larger than in a Galilean telescope.
The Galileo Project – The telescope (Webside ikke længere tilgængelig), Astronomers eschewed the third convex lens (the erector lens) necessary for re-inverting the image because the more lenses the more optical defects multiplied
The Galileo Project – The telescope (Webside ikke længere tilgængelig), A typical astronomical telescope is the one made by Christiaan Huygens, in 1656. It was 23 feet long... it magnified about 100 times.
The Galileo Project – The telescope (Webside ikke længere tilgængelig), By the early 1670s, Johannes Hevelius had built a 140-foot telescope... The objective was mounted on a building or pole by means of a ball-joint and aimed by means of a string; the image was found by trial and error.
The Galileo Project – The telescope (Webside ikke længere tilgængelig), Others were unable to grind mirrors of regular curvature, and to add to the problem, the mirror tarnished and had to be repolished every few months, with the attending danger of damage to the curvature... The reflecting telescope became a reality in the hands of first James Hadley and then others... In the second half of the eighteenth century, in the hands of James Short and then William Herschel, the reflecting telescope with parabolically ground mirrors came into its own.

stardate.org

telescopes.stardate.org

http://telescopes.stardate.org/ – History of the Telescope – Hans Lippershey, Legend says that sometime in 1608, two children entered the shop of Hans Lippershey... The children picked up two lenses and held one in front of the other, producing a magnified image of the weathervane atop a nearby church.
http://telescopes.stardate.org/ – History of the Telescope – Hans Lippershey,The States General felt that the invention couldn’t be kept a secret, so it denied the applications. Even so, Lippershey still managed to turn a profit on his invention by selling several spyglasses to the government.
http://telescopes.stardate.org/ – History of the Telescope – Isaac Newton, And the glass contained chemical impurities that colored the lenses green.
http://telescopes.stardate.org/ – History of the Telescope – Isaac Newton, Galileo’s telescopes produced a slightly blurry view of the sky, with colored “haloes” around astronomical objects.
http://telescopes.stardate.org/ – History of the Telescope – Isaac Newton, The primary mirror, at the bottom of the telescope tube, curved inward slightly, in a spherical shape... Light from an astronomical object struck this mirror and reflected back up the telescope tube, where it hit a flat secondary mirror. This mirror, which was tilted at a 45-degree angle, in turn reflected the light to an eyepiece at the side of the tube.