| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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Naturalist's Almanac What to See This Summer
July July 4 While waiting for the Independence Day fireworks to start, impress everyone around you by pointing out Jupiter as it rises in the east, now at opposition and at its brightest. With a small telescope, spotting scope, or tripod-mounted pair of binoculars, its four largest moons are easily visible, even across a distance of a half-billion miles. "Red Tide" begins this month when a toxic phytoplankton, Gonyaulax, blooms and is consumed by shellfish. This makes shellfish dangerous to collect and eat during the summer months. Stellar sea lions arrive at Aņo Nuevo Island early this month to breed. Although they range from the shores of Alaska to California, their population has declined steadily since 1938. They were declared a threatened species in 1990. Breeding-age male elephant seals molt at Aņo Nuevo. July 12 Just before dawn--if you're in Bermuda--you can see the crescent Moon block the brilliant planet Venus from view in an event called an occultation. For the continental U.S., this will already have occurred by moonrise. July 15 New Moon. Starting tomorrow, look for a thin crescent Moon in the west just after sunset. Blue and humpback whales can be seen off the coast as they migrate north to the Bering Sea. They feed on shrimp-like animals called krill, which are abundant off the shores of northern California during the early summer. July 28 South Delta Aquarid meteor shower. The radiant, or centerpoint, of this shower rises in the east-southeast about two hours after sunset. Under optimal conditions, perhaps 20 "shooting stars" per hour, are visible, but this year the shower is hindered by moonlight. July 30 Full Moon, coinciding with perigee--or the Moon's closest approach to the Earth--and the highest tides of the year. August August 1 Mercury one-half degree of arc (about the diameter of the Full Moon) from the bright star Regulus in Leo the Lion. Look westward after sunset; binoculars will help. Blackberries are ripe for the picking. August 11-12 Peak of the Perseid meteor shower, usually averaging about 50 "shooting stars" per hour from dark locations. This shower actually has two peaks; the first one--5:00 p.m. pdt on August 11--favors Europe and Asia, but in North America check a secondary peak ten hours later--3:00 a.m. pdt on August 12. August 14 New Moon. August 19 Venus at greatest western elongation, meaning that it will rise in the east well before dawn. A telescope reveals Venus at a quarter phase and smaller than it looked on July 12 because it's farther away. White-crowned sparrows, robins and other birds continue nesting through August. August 28 Full Moon. Also called the Green Corn Moon or Grain Moon by certain Native American tribes. September Poison oak begins to turn color in late August and September. It grows in a wide variety of habitats, and in many sizes and shapes. Watch for the distinctive compound leaves with three gently lobed leaflets, which will turn bright red on the edges and underside this time of year. September 12 New Moon During the last two weeks of September and the beginning of October, Hawk Hill in the Marin Headlands is one of the best places in the state for raptor watching. Approximately 19 different species can be seen, including red-tailed and sharp- shinned hawks, and possibly golden eagles or goshawks. For more information, contact the Golden Gate Raptor Observatory at (415)331-0730. September 22 Fall equinox at 11:00 a.m. pdt. September 26 Saturn at opposition, rising at sunset against the faint stars of Pisces. September 26 Full Moon, also known as the Harvest Moon, the first Full Moon of autumn. A total lunar eclipse occurs, visible from start to finish from the east coast of North America and all of South America. For observers in the western U.S., the Moon will rise with the Earth's red shadow already starting to creep across its face. Totality is at 7:19 p.m., pdt and ends 70 minutes later. Look for the planet Saturn only three degrees away from the reddened Moon.
Compiled by Gordy Slack, Associate Editor of California Wild and Jonathan Randall, editorial intern. |
Summer 1996
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