The sky around NGC 545/547 at true scale, north up and east left, with stars to magnitude 8. The circles show the field of a low-power eyepiece and of 10×50 binoculars.
NGC 545/547 is a galaxy pair (E-S0/E) in Cetus, 250 million light-years away
NGC 545/547 (NGC 545, NGC 547, Arp 308, UGC 1007, PGC 5323) is a galaxy pair (E-S0/E) in the constellation Cetus, 250 million light-years away. It shines at magnitude 13.3 and spans 3′ × 1.9′ of sky, about 218,900 light-years across. It is a telescope object, 6 inches or larger, and it is highest in the evening sky in November.
Galaxy: a system of billions of stars, gas and dust held together by gravity, far outside the Milky Way. Spiral galaxies have a disk with arms; elliptical galaxies are smooth, round or oval swarms of older stars.
NGC 545/547 is Arp 308, one of Arp's unclassified double galaxies
Halton Arp photographed it for his Atlas of Peculiar Galaxies (1966) as field Arp 308. It is in his group of double and multiple, Arp 269 to 332, under the category Unclassified double galaxies. The field holds 2 galaxies.
NGC 545/547 lies 6.9° north of θ Cet, the magnitude 3.6 star. Three fingers held at arm's length cover about 5°.
NGC 545/547 is highest in the evening in November
The chart gives its height above the horizon at 9 pm through the year, from 60°N to 40°S. It can be seen from the whole southern hemisphere and north to about 89°N.
NGC 545/547 is 250 million light-years away
The light seen from NGC 545/547 tonight left it about 250 million years ago, long before modern humans existed. It ranks 328 of 422 by distance among the galaxies on Go Astronomy. Distance source: Cosmicflows-4 (Tully et al. 2023).
