CONSTELLATIONS
OF THE MONTH - Pisces
Ross Gould
Pisces, the fishes, is an ancient constellation,
passed to us via the Greeks from ancient Babylon, situated on the zodiac
and listed by Ptolemy. It sits between Aries and Pegasus, touching Andromeda
in the north and Cetus and Aquarius in the south. The traditional representation
of Pisces is of two fish, bound by cords around their tails.
Pisces is large in area but composed of rather faint stars, and being
distant from the Milky Way, can offer the amateur observer only double
stars and galaxies. Some of the doubles are fine coloured objects, and
the best of the galaxies is M74.
Doubles
There are plenty available - here I've listed 11, Sissy Hass's book Double
Stars for Small Telescopes (Sky Publishing, 2006) describes 27, and my
observing list includes dozens more.
STF 3009 2324.3, +0343. An easy and effective pair, orange and
white, mags. 6.9 and 8.8 at 6.6".
35 Psc 0015.0, +0849. Easy, attractive: mags. 6.1 and 7.5 at 11.4"
- good at low power and shows well in small 'scopes.
38 Psc 0017.4, +0853. A yellow pair of 7th mag. stars at 4.0".
55 Psc 0039.9, +2126. A very attractive uneven pair, mags. 5.6
and 8.5, presenting a nice colour effect of orange primary with bluish
(by contrast) secondary. Separation is 6.6".
65 Psc 0049.9, +2743. Bright even double, both stars mag. 6.3
and yellow, 4.3" apart, in a field of scattered fainter stars. Hartung:
"excellent for small apertures".
Psi-1 Psc 0105.7, +2128. One of four bright stars making a binocular
asterism (the others are Psi-2, Psi-3, and Chi Psc). Psi-1 also has a
companion, nearly as bright, at 30". Nice effect at low power.
BU 303 0109.7, +2348. Yellowish pair, very close (0.7" in
2001) and probably a long period binary. The stars are mags. 7.3 and 7.6.
Needs good seeing and preferably at least 20 cm aperture.
Phi Psc 0113.7, +2435. An uneven pair (mags. 4.7 and 9.1) at 7.8"
- colours deep yellow and white.
Zeta Psc 0113.7, +0735. Fine wide pair (23") of mag. 5 and
6 stars, yellow and white.
STF 138 0136.0, +0739. A 7th mag. pair of yellow stars at 1.7",
perhaps needing 10 cm aperture.
Alpha Psc 0202.0, +0246. A fine white pair of mags. 4 and 5, at
1.9" (2004). It is a long period binary (P = c.900 years).
Galaxies
There are not many bright galaxies in Pisces, and even M74 benefits greatly
from a larger aperture. The following short list is a starting point.
Those with larger scopes (30 cm or more) or with CCD cameras can pursue
many fainter examples.
NGC 488. 0121.8, +0515. Galaxy with moderately bright core and
hazy surround, a little elongated.
NGC 520 0124.6, +0348. Two irregular galaxies, described as "two
parallel bright streaks
separated by a dark lane". Faint with
20 cm, seeing detail probably needs at least 30 cm and, as so often with
galaxies, a very dark sky. (Photo in negative form, to show details better.)
NGC 524 0124.8, +0932. Not difficult with 20 cm, but showing little
detail - a round halo with a bright tiny core. Larger apertures show some
other galaxies nearby (see photo).
M74 (NGC 628) 0136.7, +1547. Discovered by Mechain in 1780, and
seen by Messier soon after, it has a reasonably bright central region
with a larger fairly faint circular halo. Hartung saw hints of the spiral
arms with 30 cm ("
suggestion of concentric zoning").
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