Star

Mira

Also Omicron Ceti · 68 Ceti

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Mira — GALEX, ultraviolet; Mira's 13-light-year tail — GALEX, ultraviolet; Mira's 13-light-year tail. Credit: NASA/JPL-Caltech. Licence: Public domain (NASA). Source

A pulsating red giant that brightens and fades over about 11 months, the prototype of the long-period variables named after it.

Measured

Distance: about 300 light-years (published estimates 270–340)
Constellation: Cetus
Position (J2000): RA 2h 19m 21s, Dec −2.98°

How far, from the Sun

About 300 light-years. To cross it:

Light300 years
Voyager 1's speed5.33 million years
Driving at 100 km/h3.24 billion years

Voyager 1 at the speed it moved outward over the year to 2026-10-25 (JPL Horizons). Driving: nonstop, never refuelling.

Facts

It swings from about magnitude 3, sometimes 2, down to 10 over a cycle of about 332 days.
David Fabricius is credited with discovering its changing brightness in 1596.
In 2007 the GALEX telescope found a 13-light-year tail of gas trailing behind it.
Johannes Hevelius named it Mira, "The Wonderful", in 1642.

Where this comes from

Hipparcos parallax 10.91 ± 1.22 mas (van Leeuwen 2007, A&A 474, 653)

Every catalogue Ouranos draws is credited on the credits page.