Astronomy Picture of the Day ·

Pluto's P4

The Astronomy Picture of the Day for July 22, 2011 is “Pluto's P4,” an image. It is credited to Credit: NASA , ESA , Mark Showalter ( SETI Institute ). The original explanation runs about 160 words.

Pluto's P4
Credit: NASA , ESA , Mark Showalter ( SETI Institute ) Shown from science.nasa.gov. Not hosted by OpenOrbit.

From the explanation

“Nix and Hydra were first introduced to human eyes in Hubble Space Telescope images from May 2005 , as Pluto’s second and third known moons. Now Hubble images have revealed a fourth satellite for the icy, dwarf planet.”

— APOD editors, July 22, 2011

Read the full explanation on science.nasa.gov

At a glance

Date
July 22, 2011
Type
Image
Credit
Credit: NASA , ESA , Mark Showalter ( SETI Institute )
Copyright
No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length
About 160 words

All of July 2011 → · 2011 by month → · Full archive since 1995 →

Topics in this entry

Hubble Space Telescope

Topics are matched from words in the title and explanation.

On this day: July 22 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.