International Astronomical Union

Table of Contents

Introduction References & Edit History Quick Facts & Related Topics

Videos

How do features on Pluto and its moons get their names?

Why isn't Pluto a planet?

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Remarkable new details of Pluto's largest moon Charon are revealed in this image from New Horizons' Long Range Reconnaissance Imager (LORRI), taken late on July 13, 2015 from a distance of 289,000 miles

Why Is Pluto No Longer a Planet?

Planet Earth and lunar moon from space

Where Did the Moon Come From?

solar eclipse, sun, moon, astronomy, space

How Do You Tell the Difference Between Total, Annular, Solar, and Lunar Eclipses?

Arrangement of the phases of the moon in total eclipse with Blood Moon

9 Celestial Omens

1 July 2002: The Solar and Heliospheric Observatory (SOHO) satellite reveals a massive solar eruption more than 30 times the Earth's diameter. The eruption formed when a loop of a magnetic field over the surface of the Sun trapped hot gas.

6 Questions About the Sun Answered

Discover

Ice Sledge Hockey, Hockey Canada Cup, USA (left) vs Canada, 2009. UBC Thunderbird Arena, Vancouver, BC, competition site for Olympic ice hockey and Paralympic ice sledge hockey. Vancouver 2010 Olympic and Paralympic Winter Games, Vancouver Olympics

10 Best Hockey Players of All Time

Facsimile of one of William Henry Ireland's forgeries, a primitive self-portrait of William Shakespeare(tinted engraving). Published for Samuel Ireland, Norfolk Street, Strand, December 1, 1795. (W.H. Ireland, forgery)

The Time a Law Clerk Successfully Forged a New Shakespeare Play to Impress His Dad

Scottish fold cat. A genetic mutation caused (in the original cat-1961) the ears to bend forward and down.

Shorthair Cat Breeds

Ahura Mazda - relief of the Zoroastrian god Ahura Mazda at the ancient ruins of Persepolis in Iran. Also known as Ormazd Zoroastrianism,

Which Religion Is the Oldest?

Srinivasa Ramanujan, Indian mathematician and autodidact.

6 Interesting Facts about Srinivasa Ramanujan

Fish. Lionfish. Lion-fish. Turkey fish. Fire-fish. Red lionfish. Pterois volitans. Venomous fin spines. Coral reefs. Underwater. Ocean. Red lionfish swims by seaweed.

10 of the World’s Most Dangerous Fish

Close-up of ostriches (Struthio camelus) necks and heads; location unknown.

6 of the World's Most Dangerous Birds

International Astronomical Union: Media

Videos

How do features on Pluto and its moons get their names?

How do features on Pluto and its moons get their names?

Learn how physical features on Pluto, Charon, and nearby moons are named according...

Video: Encyclopædia Britannica, Inc.

Why isn't Pluto a planet?

Why isn't Pluto a planet?

Being a dwarf planet isn't really a downgrade.

Video: Encyclopedia Britannica INC.

VIEW MORE in these related Britannica articles: