Summer's coming on, and it's star party time in the Great Southwest.
Potential participants have choices to make because most of the big regional events take place around the same dates (on moonless nights).
Amateurs have been gathering for star parties at the Grand Canyon's South Rim since 1991 and the North Rim since 1994. This year, both are scheduled for June 13-20. For South Rim details, check online at http://tucsonastronomy.org/ gcsp.html. For the North Rim, it's http://saguaroastro.org.
The ninth annual Astronomy Festival at Bryce Canyon National Park, Utah, (www. nps.gov/brca) takes place June 17-20, as does the annual Rocky Mountain Star Stare (http://rmss.org). It's planned for a dark-sky site near Gardner, northwest of Walsenburg.
By all means, check out the Night-Sky Archaeoastronomy Program at Chimney Rock Archaeological Area near Pagosa Springs. June's session is on the 19th. Expect music, talks, tales and telescopes. Visit chimneyrockco.org for details and other program dates.
A night sky program is offered Tuesdays, Fridays and Saturdays at Chaco Culture National Historical Park (www.nps.gov/chcu) throughout the summer in a magical setting. And there may be astro events in the local area. Visit the online newsgroup at groups.google.com/group/Four-Corners-Stargazers.
Speaking of summer, this year in our time zone, it occurs on June 20, at 11:46 p.m. Those of us who have been getting up and out before dawn have been greeted in the eastern sky by co-morning "stars," Jupiter and Venus.
Venus, by far the brighter of the two (magnitude minus 4.3), is low in the east about 4 a.m. with Jupiter (magnitude minus 2.5) higher in the southeast. Jupiter will rise earlier each night and pull away from Venus. Viewing the giant planet in a telescope during morning twilight reduces the planet's glare and makes it easy to spot the four Galilean moons and the planet's main cloud bands.
Faint Mars (magnitude 1.1) will catch up to and pass Venus during June. The proximity of the two will make it relatively easy to spot the "Red Planet." Have a look about 4:30 a.m. on the 19th. Mars will be snuggled between Venus and the waning crescent moon.
Tiny Mercury, the innermost planet, reaches its greatest western elongation on the 13th. That means it will appear near the eastern horizon before sunrise. Shining at magnitude 0.5, it won't be easy to locate. It might be easiest to spot on the morning of the 21st when a tiny sliver of moon will be about 6 degrees east of Mercury. You'll need binoculars or a small telescope to pick them out of twilight a little after 5 a.m. just above the horizon.
Saturn continues to dominate the evening sky, although it sets earlier each evening, dropping into twilight by the end of June. It can be found in Leo, forming an irregular triangle with the bright stars Regulus and Algieba. The 6-day-old crescent moon will hover nearby on the 27th.
Lewis McCool gazes at stars through a 10-inch Dobsonian from his Dolores home.