Astronomy Picture of the Day · April 23, 1999

Io Shadow

The Astronomy Picture of the Day for April 23, 1999 is “Io Shadow,” an image. It is credited to Credit: John Spencer (Lowell Observatory), NASA. The original explanation runs about 131 words.

From the explanation

“Orbiting Jupiter once every 43 hours, the volcanic moon Io cruises 500,000 kilometers above swirling, banded cloud-tops. 5 hours, the Hubble Space Telescope watched as Io accompanied by its shadow crossed the face of the reigning gas giant planet in 1997.”

— APOD editors, April 23, 1999

Read the full explanation on science.nasa.gov

At a glance

Date: April 23, 1999
Type: Image
Credit: Credit: John Spencer (Lowell Observatory), NASA
Copyright: No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length: About 131 words

All of April 1999 → · 1999 by month → · Full archive since 1995 →

Topics in this entry

Jupiter Hubble Space Telescope

Topics are matched from words in the title and explanation.

On this day: April 23 in other years

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Source

Astronomy Picture of the Day, April 23, 1999 — science.nasa.gov/image-article/apod-1999-april-23-io-shadow

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.