Eye on the Sky

The June Sky

Paul Curtin

The moons of Jupiter provide excitement this month with a string of double shadow transits. In preparation, observers should gain some experience distinguishing Jovian cloud features. See Gupta for transit timings. For those getting started in planetary observing, the works of Price, Moore, Kepple or Sherrod provide a solid foundation.

Although the main section of Draco has been in our sights for several months, it is only in June that we concentrate on the Dragon. Draco's head is composed of a quadrilateral sometimes called the "Lozenge." From the Lozenge, follow the string of stars northeast and then due west towards Ursa Major. Although it boasts many double stars, Draco is rather lacking in deep sky objects. One notable exception is the planetary nebula NGC 6543, due north of the Lozenge. See Kepple for finder charts.

Returning to the Big Dipper, we follow the arc of the handle east and south to the bright star Arcturus in Bootes. Neither Bootes, with its distinct kite shape, nor Corona Borealis, a small cup shaped constellation due east of Bootes, have deep sky objects for small telescopes. Scan both constellations for double stars.

East of Corona is Hercules, with its characteristic asterism known as the Keystone. M13, a bright globular cluster, can be found one quarter of the way between the western stars of the Keystone. M92 is another globular located almost halfway between the Keystone and the Lozenge in Draco.

South of Hercules is the head of Serpens, Serpens Caput with M5, a spectacular globular cluster near the border with Virgo. Western Ophiuchus has M10 and M12, both impressive globular clusters, and M107 a much smaller and fainter globular to the south.

Libra, though important as the sometime host of planets, is otherwise devoid of interesting objects for small and medium size telescopes.

South of Libra we find Lupus, the Wolf. Lupus has star clouds, planetary nebulae and some open clusters of note. Centaurus wraps around Lupus in the south with bright Rigil-Kentaurus blazing in the sheen of the Milky Way. Beta Centauri, known as Hadar, is the other bright star in this region.

The Milky Way ends south of Circinus and Triangulum Australe, and the region near the south celestial pole seems dark and uninviting.

The Planets in June

Mercury slips into the evening sky toward the end of June. Look for it near Saturn on 26 June and Venus on 27 June.

Venus can be seen in the evening twilight.

Mars grows steadily brighter and higher in the morning sky.

Jupiter is visible until after midnight. This month brings us a large number of double shadow transits. See Gupta for times.

Saturn is low in the west just after sunset.

Bibliography

Burnham, Robert Jr., Burnham's Celestial Handbook, New York: Dover, 1978.

Dobbins, T., Parker, D., Capen, C. Introduction to Observing and photographing
the Solar System. Richmond, Virginia: Willman-Bell, 1988.

Gupta, R. (ed.), Observers Handbook 2005, Toronto: University of Toronto Press, 2004.

Kepple, G. R., Sanner, G. W., The Night Sky Observers Guide, Richmond, Virginia: Willman-Bell, 1999.

Moore, P. (ed.), Practical Amateur Astronomy, London: Lutterworth Press, 1975.

Sherrod, P. C., Koed, T. L., A Complete Manual of Amateur Astronomy. Mineola: Dover Publications, 2003.

Tirion, W., Rappaport, B., Remaklus, W., Uranometria Deep Sky Atlas, Richmond, Virginia: Willman-Bell, 2000.

Price, F. The Planet Observer's Handbook, Cambridge: Cambridge University Press, 1994.

Webb, T. W., Celestial Objects for Common Telescopes, New York: Dover, 1962.