Astronomy Picture of the Day 4-05-03

NASA ^ | 4-05-03 | Robert Nemiroff and Jerry Bonnell

[petuniasevan]

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2003 April 5

The Seasons of Saturn
Credit: R. G. French (Wellesley College) et al., Hubble Heritage Team (AURA / STScI / NASA)

Explanation: Since Saturn's axis is tilted as it orbits the Sun, Saturn has seasons, like those of planet Earth ... but Saturn's seasons last for over seven years. So what season is it on Saturn now? Orbiting the equator, the tilt of the rings of Saturn provides quite a graphic seasonal display. In fact, this month, Saturn's rings will reach their most "open" angle after appearing nearly edge on in the mid-1990s. The ringed planet is also well placed in evening skies providing a grand view as summer comes to Saturn's southern hemisphere and winter to the north. The Hubble Space Telescope took the above sequence of images about a year apart, starting on the left in 1996 and ending on the right in 2000. Although they look solid, Saturn's Rings are likely less than 50 meters thick and consist of individually orbiting bits of ice and rock ranging in size from grains of sand to barn-sized boulders.

[petuniasevan]

Just like yesterday, the weather here was atrocious. On top of the ice glaze, we had 5 inches of snow. I had no time to do the APOD as the driveway needed shoveling before I could get out and to work this early AM.

Saturn is much brighter when its rings are "open" (tilted so we can see them). When the rings are wide open, Saturn can appear as bright as magnitude -0.5, and when the rings are edge-on it can appear as dim as magnitude +1.

Here is Saturn with the rings edge-on, also courtesy of Hubble:

[petuniasevan]

[Soaring Feather]

Thank you so much. These images are fabulous!!

[xJones]

Thanks for all your hard work! Beautiful.

[firewalk]

Thanks for the ping (hope you have a good weekend)

[mtngrl@vrwc]

Thanks for the post! I am going to get my telescope out tonight and check out Saturn while it's showing off.

[sistergoldenhair]

Beautiful.
Thanks for your hard work on APOD.