Nepedia
Back to Discover
Fluent Reader
🚀

Quadrans Muralis

space Maturity 11-13 Next article →

Long ago, people saw a special shape in the night sky.

Sidney Hall - Urania's Mirror - Bootes, Canes Venatici, Coma Berenices, and Quadrans Muralis
Sidney Hall - Urania's Mirror - Bootes, Canes Venatici, Coma Berenices, and Quadrans Muralis

This shape was called Quadrans Muralis. Its name means a wall-mounted quadrant. A quadrant is a tool used to map stars. This constellation is now obsolete. That means it is no longer an official group of stars. It was once a real part of the star maps.

Quadrans Muralis Constellation Position
Quadrans Muralis Constellation Position

This constellation worked like a map for the sky. An astronomer named Jérôme Lalande created it in 1795. He used a quadrant to chart the celestial sphere. His nephew, Michel Lefrançois de Lalande, helped him with this work. They named it Le Mural in a French atlas. The shape sat between the constellations Boötes and Draco. It was also near the tail of Ursa Major.

Sidney Hall - Urania's Mirror - Bootes, Canes Venatici, Coma Berenices, and Quadrans Muralis
Sidney Hall - Urania's Mirror - Bootes, Canes Venatici, Coma Berenices, and Quadrans Muralis

Other people changed the shape over time. Johann Elert Bode made changes in 1801. He made a star atlas called Uranographia. He shrank the constellation a little bit. He did this to avoid clashing with nearby constellations. In Lalande's version, the brightest star was 44 Boötis. In Bode's version, the brightest star was CL Draconis. The star 39 Boötis was a double star moved into the shape.

Rules for the sky changed in the 1900s. In 1922, the International Astronomical Union made an official list. This group is called the IAU. They formalized the list of recognized constellations. They left Quadrans Muralis off this official list. This is why it is no longer used today. However, some parts of it still have names. The variable star BP Boötis was once a member of this group.

Even though the shape is gone, its name lives on. We still use the name for the Quadrantid meteor shower. This is a show of shooting stars in the sky. A star also carries the name today. The star 44 Boötis A is very important. In 2025, the IAU Working Group on Star Names gave it a name. They named that star Quadrans. It links back to the old constellation.

Quadrans Muralis Constellation Position
Quadrans Muralis Constellation Position
331 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (2)
File:Quadrans Muralis Constellation Position.jpg
Quadrans Muralis Constellation Position.jpg
File:Sidney Hall - Urania's Mirror - Bootes, Canes Venatici, Coma Berenices, and Quadrans Muralis.jpg
Sidney Hall - Urania's Mirror - Bootes,...
More to explore

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.