BLOOMINGTON, Ind. - April will present a rare opportunity for even casual observers to easily see several bright planets in the western sky after sunset.

This will be the best gathering in nearly two decades for the five planets visible with the unaided eye: Mercury, Venus, Mars, Jupiter and Saturn. The tightest grouping and the best pairings and clusters will happen in May and early June, but during April, viewers can watch each night as the planets assemble.

Every April evening at dusk, Jupiter, Saturn, Mars and Venus will be visible in that order from upper left (south) to lower right (west). Mercury will appear at the bottom of the line near the west-northwestern horizon during the second half of the month. Jupiter will be very high in the west at the upper end of the line.

Yellow Saturn will be accompanied by the bright orange star Aldebaran to its lower left (south). To the right (north) of Mars will be the Pleiades star cluster. Brilliant white Venus will be by far the brightest of the group, and orange Mars will be the faintest.

Anyone with a clear view of the western sky will be able to see these planets as they converge, without special equipment. Viewing information and graphics displaying the different combinations that will form are available at http://www.space.com/spacewatch/. Images are available for republication by the media at http://www.space.com/spacewatch/press_planet_images.html. (NOTE: These are not NASA sites)