Magazine article Natural History

The Sky in May

Magazine article Natural History

The Sky in May

Article excerpt

Mercury readies superior conjunction, passing behind the Sun's disk, on May 1H. one day after the planet crosses the ecliptic and begins to move north against the sky. Because it will also be at perihelion (the planet's closest approach to the Sun) on the 2 1st, the speedy planet \vill quickly move into view by about the 29th. On that night Mercury begins a good apparition that lasts through June. With binoculars, look for it low in the westnorthwest during evening twilight. Thirty minutes after sunset Mercury shines bright at magnitude -I.I. about five degrees above the horizon.

Venus doesn't rise until shortly after first light. Once it does, however, it is so bright that its rays easily pierce the advancing veil of daylight. The planet continues to rise at dawn every morning as viewed from the mid-northern latitudes, but it doesn't get very high before it's lost in the glare of sunrise. Venus recedes from Earth as it races ahead of us in its faster orbit around the Sun. A slender crescent Moon appears well to the left and slightly above Venus on the morning of the 24th.

Mars is in the western evening sky, appearing only one-fortieth as bright as it did six months ago. And the Red Planet continues to fade, dimming in magnitude from 1.5 to 1.7. All month, it is comparable in brightness to the stars Castor and Pollux, in the constellation Gemini, the twins. Mars forms a nearly perfect straight line with Castor and Pollux on the evening of the 31st. Watch the stars for a few days before and after that date for a clear view of Mars's motion. This month. Mars moves twenty degrees east, through Gemini and into the boundaries of the dim constellation Cancer, the crab. A thin crescent Moon appears above and to the right of Mars on the evening of the 30th.

Jupiter is in the western part of the constellation Libra, the scales, this month. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.