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Gacrux
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Two intersecting circles with eightfold turns but not in steps of 45░. A jumbling-only puzzle.

Gacrux /??Škr?ks/, Gamma Crucis (abbreviated Gamma Cru, ? Cru), is the nearest class M giant star to the Sun. With an apparent visual magnitude of +1.63, this is the third-brightest star in the southern constellation of Crux (the Southern Cross) and is listed 26th of the brightest stars in the night sky. A line from the two "Pointers", Alpha Centauri through Beta Centauri, leads to within 1░ north of this star. Distance has been determined using parallax measurements made during the Hipparcos mission, yielding 88.6 light-years (27.2 parsecs) from the Sun.
Gacrux, Gamma Crucis.
This star was known to the ancient Greeks and Romans, but oddly in the era lacked a traditional name. The astronomer Ptolemy counted it as part of the constellation of Centaurus. The historical name Gacrux was coined by astronomer Elijah Hinsdale Burritt (1794-1838).

Gacrux has the MK system stellar classification of M3.5 III. Although only 30% more massive than the Sun, at this stage the star has expanded to 84 times the Sun's radius. It is radiating roughly 820 times the luminosity of the Sun from its expanded outer envelope.
The atmosphere of this star is enriched with barium, which is usually explained by the transfer of material from a more evolved companion. Typically this companion will subsequently become a white dwarf. However, no such companion has yet been detected. A +6.4 magnitude companion star lies about 2 arcminutes away at a position angle of 128░ from the main star, and can be observed with binoculars. But it is only an optical companion, which is about 400 light years distant from Earth.

In culture Gacrux is represented in the flags of Australia, New Zealand and Papua New Guinea as one of five stars which comprise the Southern Cross.
It is also featured on the Republican flag of Brazil, along with 26 other stars, each of which represents a state. Gacrux represents the State of Bahia.

The puzzle consists of two intersecting circles that rotate with eight steps per full rotation. The centres of the circles are not cut regularly. It is a jumbling-only puzzle with only three types of pieces if symmetries are ignored.

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