The Summer Triangle is high overhead at dusk. This consists of the brightest stars in Cygnus, Lyra, and Aquila. Scorpius, the Scorpion, is in the south, with the ‘teapot’ of Sagittarius to his left. From the Big Dipper’s handle, ‘arc to Arcturus’ and ‘speed on to Spica’ in the southwest. The Great Square of Pegasus rises in the east, heralding the coming autumn.
Venus remains in the west southwest at dusk this month. Look for it low to the horizon, above and a bit to the left of the point of sunset. Venus outshines everything in the sky but the Sun and Moon, so you can look for it even in twilight. Venus remains the evening star for one more month.
Jupiter is still well placed for evening observing, in the southwest right as night falls.
Saturn remains well placed for evening viewing, in the south at dusk, all month. Although significantly dimmer than Mars or Jupiter, Saturn outshines the stars near it, and is therefore just as easy to see.
Mars remains brilliant in the south southeast at dusk. Now that we’re over a month past closest approach, Earth continues to pull ahead of Mars on its faster orbit and leave Mars behind. Thus, Mars is a tad dimmer each night from now on. But the fade out is so gradual that Mars remains spectacular all month; in fact it takes until the end of the year for Mars to fade back to an average brightness. What’s more, the planet wide dust storm that hid the surface during closest approach in July seems to have abated. Recently, observers at our George Observatory have been able to make out features on Mars’ disk when looking through a telescope. Continue enjoying your views of Mars!
Moon Phases In September 2018
Last Quarter Sept. 2, 9:37 p.m. New Sept. 9, 1:01 p.m.
1st Quarter Sept. 16, 6:15 p.m. Full Sept. 24, 9:53 p.m.
Fall Is Almost Here!
At 8:54 pm on Saturday, September 22, the Sun is directly overhead at the equator, shifting southwards. Therefore, this marks the autumnal equinox, one of two days a year when everyone on Earth has the same amount of daylight. Many consider this the ‘official’ start of fall, although the actual arrival of fall weather varies from year to year. Keep in mind that air and water take some time to cool off, so even with the Sun lower in the sky, warm or even hot weather is common for us in September. This is why the fall equinox is much warmer than the spring equinox in March, when the Sun is at a similar height in the sky. For anyone in the South Temperate Zone, this is the spring equinox. Those folks can look forward to watching the leaves return and the flowers bloom during October and November.
Our annual Astronomy Day at the George Observatory is on Saturday, September 15! On Astronomy Day we have activities from 3-10 pm, and all of the telescopes, even the ones that normally cost money to look through, are free. Surf to www.astronomyday.net for more information.
George Observatory is open to the public once again! Come join us any clear Saturday night.