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Northern Lights Planetarium
Tromso, far to the north of Norway, attracts summer visitors to see the midnight sun and winter visitors to see the aurora borealis. The Northern Lights Planetarium is the northermost planetarium in the world. It's worth a visit at anytime, but extra welcome if it's too cloudy to see the sky.
Lots of astro-birthdays this week!
(1) On March 6, 1787 Joseph Fraunhofer was born. He was the greatest optical glassmaker of his day and his lenses included high quality objective lenses for telescopes. Fraunhofer also invented the spectroscope, and dark absorption lines in the spectrum of the Sun are named Fraunhofer lines in his honor. You can see a visible light spectrum with the Fraunhofer lines here: http://upload.wikimedia.org/wikipedia/commons/2/2f/Fraunhofer_lines.svg
(2) There are two birthdays on March 7th.
In 1792 John Herschel was born. The son of William Herschel – discoverer of Uranus – he was a distinguished astronomer, mathematician, chemist and pioneer of photography. When he died he was given a state funeral and buried in Westminster Abbey near Isaac Newton. You can learn more about William Herschel and his sister Caroline here: http://www.bellaonline.com/articles/art48626.asp
Henry Draper was born in 1837. He was a doctor by profession and an amateur astronomer and chemist. His father John William Draper had taken the first astronomical photograph in North America and Henry was another pioneer of astrophotography. Henry Draper took the first photograph of the Orion Nebula and went on to photograph stellar spectra. He was only 45 when he died, but his widow Anna gave a sum of money to Harvard Observatory for a star catalog as a memorial to him. Annie Cannon (http://www.bellaonline.com/articles/art28074.asp) did most of the star classification for the Henry Draper Catalog and the HD numbers are still in use. You can find out more about debt astronomy owes photography here: http://www.bellaonline.com/articles/art19545.asp
(3) On March 9, 1564 David Fabricius was born in what is now Germany. He was a churchman, but also had an interest in astronomy. Fabricius discovered the first variable star, Mira. Observing with a telescope, he and his son Johannes found sunspots on the Sun and David Fabricius used them to provide the first evidence that the Sun rotates on its axis.
(4) Urbain LeVerrier was born on March 11, 1811. He was the French mathematician who calculated the position of the unknown planet that was disturbing the orbit of Uranus. He sent his calculations to Johan Galle at the Berlin Observatory who found the planet that came to be called Neptune. You can find out more here: http://www.bellaonline.com/articles/art39799.asp
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