Contact: Barbara Anthony-Twarog, (785) 864-3910 or anthony@kubarb.phsx.ku.edu. Readers may send astronomy questions to AAlice, c/o Dept. of Physics and Astronomy, The University of Kansas, Lawrence, KS 66045. For a free star chart, enclose an SASE.
1. The planetary selection is still a little slim for this late summer month. Three of the bright planets are still very close to the sun. Only Jupiter and Saturn have pulled away enough to be easily appreciated in the latter half of the night. All the more reason to enjoy some of the dark sky wonders of late summer. One normally reliable meteor shower, the Perseids, will suffer this year because the moon will be nearly full at the shower's peak Aug. 12.
3. As August opens, Jupiter and Saturn rise after 1 a.m., while Mars and Mercury are just ahead of the sun. Mercury has enough of a lead on the rising sun that it will be about 15 degrees above the horizon as the sun is preparing to rise, still pretty low but about as good as Mercury gets. Mercury is in Gemini this week, passing south of the bright stars Castor and Pollux.
6. As early as 8:30 p.m., the sun has set. Venus is a little too close to the sun to be convenient, but if you can see within 10 degrees of the western horizon, you might try to look at Venus this evening as it passes near the great star of Leo, lovely Regulus. Regulus' name ("little king") recalls its association with the fates of kings of old. Perhaps having Venus so near would suggest a royal romance. The moon should be well away to the south, having passed first quarter phase at 8:02 p.m.
8. The summer triangle is beginning to dominate the late evening sky. This trio of bright blue stars provides a great way to learn some of the prettiest summer constellations. Nearly overhead and near a small parallelogram of stars is Vega, the brightest star in the constellation Lyra. Off to the east of Lyra lies the Northern Cross, the popular name for the constellation Cygnus, the swan. Cygnus' brightest star, Deneb, marks the top of the cross or the tail of the swan. The Arabic name for this star refers to its association with the tail of a bird.
10. Things change so quickly in the inner solar system. Already, Mercury has moved out of Gemini and into Cancer to join Mars this morning. Finding these two so close together is a treat, although they are not far ahead of the rising sun. A beautiful background is provided by one of Cancer's more famous star clusters, Praesepe, the "Beehive" cluster.
11. Although Mars has been recognized as a planet as long as people have watched the skies and is one of Earth's nearer neighbors, its two tiny moons were not discovered until 1877, well after the discoveries of the much more distant planets Uranus and Neptune. The moons are tiny and generally quite close to the much brighter planet, making them tough to spot. The discovery of Deimos was made on this date in 1877 by Asaph Hall of the U. S. Naval Observatory.
14. The moon will be full overnight, at 12:13 a.m. tomorrow. With modest binoculars, you can spot the two stars of Capricornus that flank the full moon. To the moon's upper left is Deneb Algedi, a name that refers to the tail of the goat figured in Capricornus' classical associations. To the moon's upper right is the star Nashira, also a member of Capricornus. This lovely Arabic name refers to this star as a token of good luck or good tidings.
17. August 1877 must have been quite clear, because less than a week after his discovery of Deimos, Asaph Hall discovered the other Martian satellite, Phobos. Hall was assisted and encouraged by his wife and former math professor, Angeline Stickney.
20. The third star of the summer triangle is actually brighter than Deneb, but is a little nearer the horizon for northern hemisphere observers and may not be so easy to spot. If you have learned to recognize Vega and Deneb, these two stars form the base of an inverted triangle of which Altair is the apex. You'll find Altair in its home constellation of Aquila, the eagle, to the south of Lyra and Cygnus.
22. At 1:51 p.m. the moon ticks off the last of its quarter phases for the month. That phase will be achieved near the time of moonset over eastern Kansas. It's too bad we can't see the sky behind the moon very well in the glow of daylight, because there's a nice conjunction of the moon, Jupiter and Saturn among the stars of Taurus. The good news? You can see this tableau after 2 a.m. tomorrow, except that the moon will be even deeper into the heart of Taurus.
25. By 5:30 a.m., sunrise is still an hour away but the sky is starting to get light. Mars is poised to cross the eastern horizon, while Mercury has scooted around the sun and lags behind it. The best objects in view at this hour are Jupiter and Saturn, high above the southeast horizon. Jupiter is passing through the V-shaped part of the bull constellation, Taurus, while Saturn is further west and just south of the Pleiades star cluster. These are all wonderful binocular objects.
28. Mars is moving eastward, passing today from Cancer into Leo. It joins the very old moon in this question-mark shaped constellation this morning. As autumn approaches, sunrise is creeping forward to nearly 7 a.m. in eastern Kansas.
29. At 5:19 a.m. when the moon was at new phase, both sun and moon were still an hour away from clearing the horizon. Tomorrow evening, the moon will be very young and may be difficult to see, but if you look for Venus, the young moon will not be far away. Both bodies are very low in the west as the sun sets at around 8 p.m. Mercury is even closer to the sun and probably not worth trying to see at this time.