The July Sky
Paul Curtin
Events in July: Observers in Japan, Guam and Hawaii will be able to observe the moon occult Antares on 4 July. On the 31st the duo give an encore for Southeast Europe, the Middle East, and India.
India and China will have a chance to view the total solar eclipse on the 21st.
The delta-aquarid meteor shower peaks on 29 July.
Draco is the slithery string of stars that cradles the Little Dipper. Its head hovers above Hercules, and its tail tip lies just north of the Big Dipper's bowl. Alpha (Thuban) was the north star when the pyramids were built. Mu and 41-40 are triple. Nu and psi are double. Omicron is a colorful double worth seeking out. The galaxy NGC 3147 is not far from lambda. M 102 (NGC 5866) is a galaxy south of iota. The planetary nebula NGC 6543 is on the line between delta and zeta.
Find the keystone shape east of Corona Borealis. This is the main body of the constellation Hercules. M 13 is a very impressive globular cluster one-third of the way south on the line from eta to zeta. M 92, another globular, can be found by star hopping from pi, iota or sigma. Kappa, gamma, and rho are triple. Delta and mu are multiple. Alpha is a beautiful pair.
South of Hercules is the large form of Ophiuchus. Alpha Herc is west of alpha Oph. Rho and 24 are double. Lambda, 36, tau and 70 are multiple.
There are many globular clusters in Ophiuchus, among them are M 107, M 12, M 10, M 62, M 19, M9, and M 64. Note also the open cluster M 14 southwest of gamma. In dark skies look for the Pipe Nebula that occupies a large region east of theta.
South of Ophiuchus is the striking figure of Scorpius. Beta, delta, and pi constitute the head. Antares is the red giant challenging Mars for ruddy distinction. The southern section of the body ends in a sparkling stinger set fast in the shimmering Milky Way. Epsilon is triple. Beta, nu, 12 and alpha are double. This is a wonderful region filled with star clouds, open and globular clusters. Look for M 80, a globular cluster east of delta. M 4 is a nice globular west of alpha. M 6 is an open cluster north of lambda (the end of the stinger). M 7 is another open cluster east and north of lambda.
Moving south from the scorpion's stinger we find box-shaped Ara. This is a nice area of the Milky Way. NGC 6397 is a fantastic globular cluster. IC 4651 is an open cluster near alpha. NGC 6188 is an emission and reflection nebula with the open cluster NGC 6193 at its center. These can be found north of epsilon. NGC 6208 is an open cluster found by star hopping from zeta.
The triangle south of Ara is the aptly named Triangulum Australe. Epsilon, Rmk 20, and iota are double. NGC 5844 is a very nice planetary nebula. NGC 5938 is a galaxy. NGC 6025 is a very rich open cluster.
Planets in July
Mercury is too close to the sun to observe, unless you have the good fortune to observe this month's solar eclipse!
Venus is a very bright morning object.
Mars is in the morning sky in Taurus.
Jupiter is a bright morning sky object.
Saturn is in Leo and becomes harder to observe as it sinks into the evening dusk.
Bibliography
Burnham, Robert Jr., Burnham's Celestial Handbook, New York: Dover, 1978.
Cooper, I., Kay, J., Kepple, G. R. The Night Sky Observers Guide, volume 3, Richmond, Virginia, Willman-Bell, 2008.
Kelly, P. (ed.), Observers Handbook 2007, Toronto: University of Toronto Press, 2006.
Kepple, G. R., Sanner, G. W., The Night Sky Observers Guide, Richmond, Virginia: Willman-Bell, 1999.
Tirion, W., Rappaport, B., Remaklus, W., Uranometria Deep Sky Atlas, Richmond, Virginia: Willman-Bell, 2000.
Webb, T. W., Celestial Objects for Common Telescopes, New York: Dover, 1962.
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The Citizen Scientist (03 July 2009).
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