Spring Star Chart
As the drama of the universe takes stage with the waning of evening twilight, look southeast for the famous ringed world, Saturn.

Glowing like a 0-magnitude star, Saturn is currently in the foreground of the stars of the constellation Virgo the Virgin. Saturn appears yellowish. Looking further down (east) is the bright bluish-white star Spica, which we might imagine as Miss Virgo’s diamond ring star (maybe she’s spoken for after all).

Ahead of Saturn, to the west and seen high in the south-southeast in early evening is the bright bluish-white star Regulus, the brightest star in Leo the Lion. To the lower left of rising Saturn, due east, is the brilliant orange star Arcturus, being enjoyed by constellation Bootes the Herdsman (he needs his citrus).

The Ringed Planet, in the midst of these bright stars and innumerable dimmer stars, provides a starling view in even a small telescope. If you have a telescope magnifying only about 30x, you will see at once that Saturn is unlike the view of any star. Appearing very small at this magnification, you nevertheless will see Saturn as a tiny round ball encircled by a bright ring.

You will see that the ring is foreshortened due to the perspective with our line of sight.

Close by you will find what appears to be a dim star. Of course there may always be dim stars nearby, as Saturn moves gradually along night to night passing the stars far in the background.

One “star,” however, never goes away and follows Saturn, making a loop around it once every 15 days and 22 hours, like clockwork.

This is Titan, the largest and brightest of Saturns’ family of 62 known moons. Titan is larger than our own moon and even the planet Mercury. Discovered in 1655, the satellite as known to have a thick atmosphere, our knowledge of this intriguing world catapulted with the arrival of NASA’s Cassini mission in 2004.

Images:Nasa
Still going strong, the Cassini probe orbits Saturn making detailed study of the planets and rings, and system of satellites. In January 2005, a probe carried by Cassini, known as Huygens, made a soft landing on Titan. Incredible images were transmitted during descent and from the ground, complementing ongoing radar analysis which peeks through the perpetual, dense haze. Titan was found to be a world of wind and rain, with sand dunes, mountain ranges, rivers and lakes.

Hardly a paradise for future astro-tourists, the liquid isn’t water. Titan flows with methane. The satellite is also unbearably cold at the surface, minus 290 degrees Fahrenheit.

In your telescope, however, Titan looks like a star. Some observers can pick out an orange hue. The main attraction in the eyepiece, however, is always the rings. If you have a telescope with a 6-inch-wide aperture or bigger, if the air is steady you should be able to discern not one, but two rings. There are actually thousands of concentric rings.

The planet itself presents a brighter band in its mid-section and a dark top. You are looking at the top of the planet’s perpetual shroud of clouds.

NASA and the Jet Propulsion Laboratory maintains a web site for the Cassini-Huygens mission, at saturn.jpl.nasa.gov/.

First-quarter moon is on April 11.

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