Sunday, November 16, 2025

APOD - Crossing Saturn's Ring Plane

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.

2025 November 16
The planet Saturn is shown as an orange orb with bands.  A blue line with bumps runs across the middle -- which is   the rings seen sideways. The bumps are small moons.  Please see the explanation for more detailed information.

Crossing Saturn's Ring Plane
Image Credit: NASA, ESA, JPL, ISS, Cassini Imaging Team; Processing: Fernando Garcia Navarro

Explanation: If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear. This is because Saturn's rings are confined to a plane many times thinner, in proportion, than a razor blade. In modern times, the robotic Cassini spacecraft that orbited Saturn frequently crossed Saturn's ring plane during its mission to Saturn, from 2004 to 2017. A series of plane crossing images from 2005 February was dug out of the vast online Cassini raw image archive by interested Spanish amateur Fernando Garcia Navarro. Pictured here, digitally cropped and set in representative colors, is the striking result. Saturn's thin ring plane appears in blue, bands and clouds in Saturn's upper atmosphere appear in gold. Details of Saturn's rings can be seen in high dark shadows. The moons Dione and Enceladus appear as bumps in the rings.

Tomorrow's picture: unusual comet tail


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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
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& Michigan Tech. U.


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Saturday, November 15, 2025

APOD - Andromeda and Friends

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.

2025 November 15
See Explanation.  Clicking on the picture will download  the highest resolution version available.

Andromeda and Friends
Image Credit & Copyright: Piotr Czerski

Explanation: This magnificent extragalactic skyscape looks toward the Andromeda Galaxy, the closest large spiral galaxy to the Milky Way. It also accomplishes a Messier catalog trifecta by including Andromeda, cataloged as Messier 31 (M31), along with Messier 32 (M32), and Messier 110 (M110) in the same telescopic field of view. In this frame, M32 is just left of the Andromeda Galaxy's bright core with M110 below and to the right. M32 and M110 are both elliptical galaxies themselves and satellites of the larger spiral Andromeda. By combining 60 hours of broadband and narrowband image data, the deep telescopic view also reveals tantalizing details of dust lanes, young star clusters, and star-forming regions along Andromeda's spiral arms, and faint, foreground clouds of glowing hydrogen gas. For now, Andromeda and friends are some 2.5 million light-years from our own large spiral Milky Way.

Fun Fact: It has been 11,111 days since APOD was founded.
Tomorrow's picture: crossing the plane


< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Amber Straughn Specific rights apply.
NASA Web Privacy, Accessibility, Notices;
A service of: ASD at NASA / GSFC,
NASA Science Activation
& Michigan Tech. U.


This is an automated email. If you notice any problems, just send me a note at gtracy@gmail.com. You can add and remove email addresses to this distribution list here, https://apodemail.org.Unsubscribe