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UFO

03 Mai 2012 08:42



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 an observer can see the nebula clearly in a telescope using an OIII filter (a filter isolating the wavelength of light from doubly ionized oxygen), as almost all light from this nebula is emitted at this wavelength. An 8-inch (200 mm) telescope equipped with an OIII filter shows the delicate lacework apparent in photographs, and with an OIII filter almost any telescope could conceivably see this nebula. Some argue that it can be seen without any optical aid except an OIII filter held up to the eye.
sursa-wiki.

Felicitari pentru muncă ! 
Resturile unei supernove aflate la ... 1500 de ani lumină. Obiectul a fost văzut pentru prima dată chiar de sir William Herschel în 1784.