|
Some daily events in the changing sky for October 3 ¨C 11.
Watch the Moon wax in the west from night to night, passing Venus and fainter Antares. (These scenes are drawn for the middle of North America. European observers: move each Moon symbol a quarter of the way toward the one for the previous date. For clarity, the Moon is shown three times actual size.)
Friday, October 3
In twilight, look for summery Antares still glimmering barely in view low in the southwest. It's upper left of the crescent Moon, as shown here.
Saturday, October 4
Antares twinkles to the right of the Moon early this evening.
Sunday, October 5
Jupiter's moon Europa emerges out of eclipse by Jupiter's shadow around 8:30 p.m. EDT, just east of the planet. A small telescope will show it gradually swelling into view.
As the Moon waxes through the week, watch it pass Jupiter and the Sagittarius Teapot. (The blue10¡ã scale is about the size of your fist held at arm's length).
Monday, October 6
Get a low-power scope onto Venus low in the west-southwest as twilight fades, and look for the wide double star Alpha Librae less than 1¡ã to its north (upper right). This direction is correct at the time of twilight in North America. Venus itself is tiny (13¡å wide) and gibbous.
Jupiter is the thing shining above the Moon this evening. Jupiter is now at eastern quadrature, 90¡ã east of the Sun.
Tuesday, October 7
First-quarter Moon (exact at 5:04 a.m. EDT). This evening, Jupiter shines to the Moon's right.
Wednesday, October 8
Jupiter's moon Io emerges out of eclipse by Jupiter's shadow around 9:47 p.m. EDT, just east of the planet. A small telescope will show it gradually swelling into view.
This Week in the night time sky:
Monday, September 15
Full Moon isn't when most observers turn their telescopes Moonward. But have you ever looked closely for the subtle gray shadings ¡ª and even slight colors ¡ª in the flat lunar maria? Now's the time to try! See Chuck Wood's "Exploring the Moon" column in the September Sky & Telescope, page 60.
With binoculars, watch Spica join in with Venus, Mercury, and Mars as the planets go through their evolving positions.
Tuesday, September 16
In bright twilight, look with binoculars for the 6¡ã diamond of Venus, Spica, Mercury, and Mars very low in the west-southwest, as shown above.
Ganymede, Jupiter's largest moon, casts its shadow onto Jupiter's face from 10:41 p.m. to 2:00 a.m. EDT tonight (7:41 to 11:00 p.m. PDT). For a listing of all events among Jupiter's moons this month, visible worldwide, see the September Sky & Telescope, page 58.
Wednesday, September 17
April is when the Big Dipper dumps into the Little Dipper after dark. Now with summer turning to fall, it's the Little Dipper's turn to dump into the Big Dipper at nightfall.
Thursday, September 18
Right after dusk, spot bright Jupiter in the south. Then look high above it and a bit left to spot Altair. Left of Altair, by roughly a fist width at arm's length, is the dim but distinctive constellation Delphinus, the Dolphin. The Dolphin is leaping upward and bending to the left. You'll need at least a moderately dark sky; look early before the Moon rises high.
Friday, September 19
If you're in eastern North America and have a clear view to the east-northeast, plan to get out your telescope and watch the waning gibbous Moon passing, and perhaps occulting, the Pleiades. See the September Sky & Telescope, page 64. Detailed predictions are available from the International Occultation Timing Association (IOTA). If you're in northern Europe, the occultations will be seen later in the night with the Moon high in the sky.
Space Weather News for Sept. 12, 2008
http://spaceweather.com
HARVEST MOON: This weekend's full Moon has a special name--the Harvest Moon. It's the full Moon closest to the northern autumnal equinox. In years past, farmers depended on the light of the Harvest Moon to gather ripening crops late into the night. Post-Edison, we appreciate it mainly for its beauty. Be alert in the nights ahead for Harvest Moon halos, coronas and 'dogs. Visit http://spaceweather.com for example and more information.
AURORA WATCH: Around the Arctic Circle, moonlight will compete with Northern Lights. A solar wind stream flowing from a coronal hole on the sun is due to hit Earth on Sept. 13th or 14th, possibly sparking high-latitude geomagnetic storms. Sky watchers from Alaska to Scandinavia should be alert for auroras.
September 2008 Aurora Gallery: http://spaceweather.com/aurora/gallery_01sep08.htm
| |
