To try to corroborate this theory, an image of
the emission of a planetary nebula in the recombination lines of oxygen has been obtained with the GTC.
Not exact matches
More accurate distances between the most common type
of «
planetary nebulae» and the Earth can be estimated simply with three sets
of data: firstly, the size
of the object on the sky taken from the latest high resolution surveys; secondly, an accurate measurement
of how bright the object is in the red hydrogen - alpha
emission line; and thirdly, an estimate
of the dimming toward the
nebula caused by so called interstellar - reddening.
«To do this,» explains Antonio Cabrera Lavers, head
of astronomy at the GTC and one
of the authors
of the paper, «we have used for the first time the blue tunable filter
of OSIRIS to take a deep image centred on the
emission from the recombination lines
of one
of the oxygen ions in the
planetary nebula 6778.»