Astronomy Picture of the Day ·

I Zwicky 18: The Case of the Aging Galaxy

The Astronomy Picture of the Day for October 17, 2007 is “I Zwicky 18: The Case of the Aging Galaxy,” an image. It is credited to Credit: NASA , ESA , and A. Aloisi ( ESA & STScI ). The original explanation runs about 165 words.

I Zwicky 18: The Case of the Aging Galaxy
Credit: NASA , ESA , and A. Aloisi ( ESA & STScI ) Shown from science.nasa.gov. Not hosted by OpenOrbit.

From the explanation

“How old is this galaxy? The galaxy on the left, I Zwicky 18 , was once thought to be one of the youngest galaxies on record since its bright stars indicated an age of only 500 million years.”

— APOD editors, October 17, 2007

Read the full explanation on science.nasa.gov

At a glance

Date
October 17, 2007
Type
Image
Credit
Credit: NASA , ESA , and A. Aloisi ( ESA & STScI )
Copyright
No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length
About 165 words

All of October 2007 → · 2007 by month → · Full archive since 1995 →

Topics in this entry

Galaxies

Topics are matched from words in the title and explanation.

On this day: October 17 in other years

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Source

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.