[15] In 1638 Johannes Holwarda determined a period of the star's reappearances, eleven months; he is often credited with the discovery of Mira's variability.

Certainly Algol's history (known for certain as a variable only in 1667, but with legends and such dating back to antiquity showing that it had been observed with suspicion for millennia) suggests that Mira might have been known, too.

Karl Manitius, a modern translator of Hipparchus' Commentary on Aratus, has suggested that certain lines from that second-century text may be about Mira.

The other pre-telescopic Western catalogs of Ptolemy, al-Sufi, Ulugh Beg and Tycho Brahe turn up no mentions, even as a regular star.

As with other long-period variables, Mira's deep red color at minimum pales to a lighter orange as the star brightens.

Examination of this system by the Chandra X-ray Observatory shows a direct mass exchange along a bridge of matter from the primary to the white dwarf.

This is also causing dynamic instability in Mira, resulting in dramatic changes in luminosity and size over shorter, irregular time periods.

Observations of Mira A in the ultraviolet band by the Hubble Space Telescope have shown a plume-like feature pointing toward the companion star.

The 6,000 to 7,000 known stars of this class[24] are all red giants whose surfaces pulsate in such a way as to increase and decrease in brightness over periods ranging from about 80 to more than 1,000 days.

In the particular case of Mira, its increases in brightness take it up to about magnitude 3.5 on average, placing it among the brighter stars in the Cetus constellation.

Combined with the overall luminosity changes, this creates the very big visual magnitude variation with the maximum occurring when the temperature is high.

[10] Ultraviolet studies of Mira by NASA's Galaxy Evolution Explorer (GALEX) space telescope have revealed that it sheds a trail of material from the outer envelope, leaving a tail 13 light-years in length, formed over tens of thousands of years.

Mira's bow shock will eventually evolve into a planetary nebula, the form of which will be considerably affected by the motion through the interstellar medium (ISM).

[31] Mira’s tail offers a unique opportunity to study how stars like our sun die and ultimately seed new solar systems.

As Mira hurls along, its tail drops off carbon, oxygen and other important elements needed for new stars, planets, and possibly even life to form.

These observations also hinted that the companion was a main-sequence star of around 0.7 solar mass and spectral type K, instead of a white dwarf as originally thought.