Colossal moon Titan casts a shadow on Saturn's cloud tops early on Sept. 4. Will you be able to see it?

Heads up stargazers! The shadow of Saturn's largest moon Titan will skim across the gas giant's swirling cloud tops in the early morning hours of Sept. 4. Here's everything you need to know about how to catch the rare transit event.

Once every 15 years, the orbital mechanics of the solar system bring Saturn's iconic rings — and the orbit of Titan — into an edge-on alignment with Earth, opening a season of shadow transits in which the silhouette of the vast moon can be seen crossing the gas giant's surface

When and where to look

The next shadow transit will begin at 1:25 a.m. ET (0525 GMT) on Sept. 4, when the entirety of Titan's shadow will be visible on the upper extreme of Saturn's disk, according to Sky & Telescope. The transit will last a little under three and a half hours, during which time the moon's silhouette will travel left to right over the gas giant's surface.

Titan will be visible close to the upper left of Saturn at the beginning of the transit, with the large moons Rhea and Tethys to its left and Enceladus off to the right of the sweeping ring system. The entirety of the event will be visible to amateur astronomers in the U.S., who will find Saturn lurking below the stars of the constellation Pisces above the southern horizon in the early hours of Sept. 4.

How to view the Titan shadow transit

An 8-inch telescope at 200x magnification will provide a clear view of Titan's shadow darkening Saturn's cloud surface under good conditions, according to Hayden Planetarium instructor and lecturer Joe Rao. You may also be able to see the umbral transit with a smaller 4-inch scope at the same magnification, though the view may appear to scintillate in the eyepiece.

Stargazers will have two further opportunities to catch Titan's shadow darkening Saturn's surface during the current shadow transit season, with the next occurring on Sept. 20 and the last taking place on Oct. 6. After that, we'll have to wait another 15 years until Saturn's rings are brought back into alignment with Earth to see the second largest moon in our solar system cast its silhouette over the majestic gas giant.

Editor's Note: If you capture an image of the Titan shadow transit and want to share it with Space.com's readers, then please send your photo(s), comments, name and the location of your shoot to spacephotos@space.com.