Celestial Atlas
PGC 9500 - 9999 ←     PGC Objects: PGC 10000 - 10499 Link for sharing this page on Facebook     → PGC 10500 - 10999
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PGC 10217 (= Maffei 2)
A 16th-magnitude spiral galaxy (type SAB(rs)bc?) in
Cassiopeia (RA 02 41 55.1, Dec +59 36 15)

PGC 10217's "recessional" velocity of -15 km/sec (actually approaching our galaxy) is too small to be used for a Hubble expansion distance estimate, but although redshift-independent distance estimates range from 9 to 18 million light years, there seems to be general agreement that the galaxy is about the same distance from us as PGC 9892. The two galaxies were discovered as part of an infrared survey by Paolo Maffei in 1968, and as a result are commonly known as Maffei 1 and 2. At the time is was thought that they might be outlying neighbors in our Local Group of galaxies, even though in the opposite direction from the other major galaxy in our Group, the Andromeda Galaxy. However, given their substantially larger distance (thought to be about 10 million light years) they are now believed to represent a different nearby group, referred to as the IC 342/Maffei Group after the largest members of that group. Maffei 1 and 2 are in the so-called Zone of Avoidance in which distant galaxies are rarely observed because of obscuration by gas and dust in the plane of our galaxy. In the case of Maffei 2, over 99% of the visible light is removed, including all bluer colors, so the galaxy is not only 7 magnitudes fainter than it would appear if not obscured, but also looks much redder than its true colors (due to blue light being blocked more than red by such obscuration). As a result, visible-light images show only very small (in comparison to the galaxies' real size), faint reddish blobs. Infrared images have to be used to get any idea of their true appearance. Some of those, such as the 2 Micron Sky Survey image shown below, present images that color different infrared wavelengths in a way that approximates the appearance the galaxies might have if they were actually visible, but others, such as the WISE image, use obviously false-color assignments for different wavelengths to show greater detail. If the 10 million light year distance assumed to apply to the Maffei objects is more or less accurate, then PGC 10217's apparent size of 5.8 by 1.6 arcmin would suggest that it is about 17 thousand light years across, but this not count extensive fainter areas rendered nearly invisible even in infrared wavelengths, and the galaxy is undoubtedly much larger than it appears. Used by the de Vaucouleurs Atlas of Galaxy Types as an example of galaxy type SAB(rs)bc.

DSS visible-light image of spiral galaxy PGC 10217, also known as Maffei 2
Above, a 12 arcmin wide region showing a visible-light image of PC 10217
Below, a "natural"-looking infrared view of a similar region (Image Credits: 2 Micron All Sky Survey)
2MASS simulated natural appearance infrared image of spiral galaxy PGC 10217, also known as Maffei 2
Below, a similar but deliberately false-color infrared view (Image Credits: NASA/JPL-Caltech/WISE Team)
WISE false-color infrared view of PGC 10217, also known as Maffei 2
Below, a half degree wide visible-light view showing Maffei 1 (PGC 9892) and Maffei 2 (PGC 10217)
DSS visible-light image centered of region between elliptical galaxy PGC 9892, also known as Maffei 1, and spiral galaxy PGC 10217, also known as Maffei 2
Below, a half degree wide false-color infrared view showing Maffei 1 (PGC 9892) and Maffei 2 (PGC 10217)
(Image Credits: NASA/JPL-Caltech/WISE Team)
WISE deliberately false-color infrared image centered of region between elliptical galaxy PGC 9892, also known as Maffei 1, and spiral galaxy PGC 10217, also known as Maffei 2

PGC 10266 (=
M77 = NGC 1068 = Arp 37)
Celestial Atlas
PGC 9500 - 9999 ←     PGC Objects: PGC 10000 - 10499     → PGC 10500 - 10999