hale to the stars I By Alan Hale
Visible Worlds in the Night Sky
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upiter and Saturn, the two largest planets of our solar system, continue to dominate the evening skies this month, being well up in the southeastern sky when darkness falls and being highest above the southern horizon during the midevening hours. Both worlds were at “opposition,” i.e., directly opposite the sun in the sky, last month, and meanwhile, both worlds are well amenable to telescopic observation, Jupiter with its cloud bands and four bright moons, and Saturn with its system of rings as well as its moons, including the large moon Titan. Rising in the east at around the same time that Jupiter and Saturn are highest is the Red Planet, Mars, which is highest above the horizon around the beginning of dawn. Mars brightens rapidly over the coming weeks as the stage becomes set for its moderately close approach to Earth (38.6 million miles) this coming October. Having emerged into our morning sky a little over a month ago, Venus now rises up to two hours before the beginning of dawn and shines brilliantly in our eastern sky during the morning hours, and indeed will do so for the remainder of this year. Our solar system’s innermost world, Mercury, may be visible very low in the dawn at the beginning of August but disappears behind the sun not too long thereafter. Meanwhile, Ceres, the largest asteroid, is at opposition late
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August 2020 • enchantment.coop
A Perseid meteor from space. This photograph was taken over China by Ron Garan aboard the International Space Station on August 13, 2011. Courtesy NASA.
in August and can be viewed with binoculars as it travels through the stars of the constellation Aquarius. The Perseid meteor shower, one of the strongest of the annual meteor showers, peaks on Wednesday morning, August 12. Under the best conditions the Perseids can produce 60 or more meteors per hour, although since the moon will be just past its Third Quarter phase at that time, this may cut down somewhat on the numbers we see this year. As their name implies, the Perseids will appear to come from the constellation Perseus, which is high in our northeastern sky during the morning hours. The Perseids are associated with Comet Swift-Tuttle, which was
independently discovered by two American astronomers in 1862, although previous returns have been identified in historical records all the way back to 69 B.C. With an approximate orbital period of 130 years, it returned most recently in 1992 and will do so again in 2126, during which time it will pass just 14 million miles from Earth on August 5 of that year.
