The Carlisle Mosquito Online

Friday, April 26, 2002


Six planets align in early May sky

A delightful alignment of the planets offers the opportunity to observe the six brightest planets in the evening sky just after dusk during the early part of May (Uranus, Neptune, and Pluto are not visible). Later in the month the moon makes a sweep through the planetary field.

Seek out a low western horizon if you want to see all six planets. The best time is between 8:30 and 9:00 p.m. Venus outshines all the other planets and is the easiest to locate. For example on May 1 at 8:30 it is about 14 degrees above the horizon just north of due west. Sunset is at 7:44 on that date (see figure). Mercury never strays far from the sun, but on May 3 it is as far from the sun as it gets (greatest elongation) and the highest in the sky. It is slightly lower and further north than Venus. There it remains for several days as it reverses its direction and begins moving toward the sun again, rapidly dimming and disappearing into the twilight.

Mars is the dimmest of the planets, reddish, and higher and slightly to the south of Venus, very close to bright Jupiter, about 2-3 degrees north. All the planets are visible to the naked eye, but Mars will be the most difficult to find especially before twilight ends, about 9:00.

The four brightest satellites of Jupiter, (Europa, Ganymede, Io, and Callisto) should be visible with a good night binocular (for example, 7x50) and they will be even more jewel-like in a small telescope. This last aid should also reveal the brightest of Saturn's satellites, Titan.

This marvelous alignment is constantly changing so check from night to night. For example, Mars makes its closest approach to Saturn on May 1. Then Venus joins in to form a tight isosceles triangle on May 5. After this Venus continues her temptation of Mars by coming as close as 1/3 degree on May 10.

On May 13, the one-day-old moon enters center stage a bit lower and to the south of Mercury. By the next night it has moved up between Venus and Mars on it way toward Jupiter which it passed between the 15

By the way, if someone in your group has trouble seeing the sixth planet, tell them to look down at their feet.

2002 The Carlisle Mosquito