glenc
23-06-2024, 06:24 AM
James Dunlop’s Galaxy Quartet, also called the Grus Quartet was found by James Dunlop in July 1826. He found the galaxies NGCs 7552 and 7582 on July 7. A week late he found NGCs 7590 and 7599.
Dunlop used a homemade 9” aperture speculum reflector that was 9’ long. Speculum is 65% copper and 35% tin. His observatory was at the back of 91 Marsden St Parramatta.
He described 7552 as "a small faint nebula (mag 10.6), rather elongated in the parallel of the equator, about 30” broad, and 40” long; there is a pretty bright point situated near the centre of the nebula: a small star (mag 9.2) precedes it." (magnitudes added by me)
For 7582 he wrote “A small faint (mag 10.5) round nebula about 30” diameter: a double nebula follows this.”
Dunlop saw 7590 and 7599 as "two very small round nebulae, nearly the same RA, and differing about 1' in polar distance." (mags 11.3 and 11.5)
This image was taken in South Africa by Leslie Rose.
NGC 7552 is on the left, then 7582, 7590 and 7599.
Dunlop used a homemade 9” aperture speculum reflector that was 9’ long. Speculum is 65% copper and 35% tin. His observatory was at the back of 91 Marsden St Parramatta.
He described 7552 as "a small faint nebula (mag 10.6), rather elongated in the parallel of the equator, about 30” broad, and 40” long; there is a pretty bright point situated near the centre of the nebula: a small star (mag 9.2) precedes it." (magnitudes added by me)
For 7582 he wrote “A small faint (mag 10.5) round nebula about 30” diameter: a double nebula follows this.”
Dunlop saw 7590 and 7599 as "two very small round nebulae, nearly the same RA, and differing about 1' in polar distance." (mags 11.3 and 11.5)
This image was taken in South Africa by Leslie Rose.
NGC 7552 is on the left, then 7582, 7590 and 7599.