Astronomy Picture of the Day · July 31, 2001

Oceans Under Jupiter's Callisto?

The Astronomy Picture of the Day for July 31, 2001 is “Oceans Under Jupiter's Callisto?,” an image. It is credited to Credit: Voyager 1 , NASA. The original explanation runs about 145 words.

From the explanation

“Why does Jupiter ‘s moon Callisto alter the magnetic field of Jupiter in its vicinity? Callisto itself does not have a strong magnetic field.”

— APOD editors, July 31, 2001

Read the full explanation on science.nasa.gov

At a glance

Date: July 31, 2001
Type: Image
Credit: Credit: Voyager 1 , NASA
Copyright: No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length: About 145 words

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Topics in this entry

Jupiter

Topics are matched from words in the title and explanation.

On this day: July 31 in other years

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Source

Astronomy Picture of the Day, July 31, 2001 — science.nasa.gov/image-article/apod-2001-july-31-oceans-under-jupiters-callisto

Copy taken Oct 28, 2026, 2:39 AM EDT. The image and explanation belong to their creators. OpenOrbit is not affiliated with or endorsed by NASA.