Characteristics
Epsilon Indi is a dwarf star of spectral type K4.5V. The star has only about three-fourths the mass of the Sun. Its surface gravity is slightly higher than the Sun's. The metallicity of a star is the proportion of elements with higher atomic numbers than helium, being typically represented by the ratio of iron to hydrogen compared to the same ratio for the Sun; Epsilon Indi is found to have about 87% of the Sun's proportion of iron in its photosphere.
The corona of Epsilon Indi is similar to the Sun, with an X-ray luminosity of 2×1027 ergs s−1 and an estimated coronal temperature of 2×106 K. The stellar wind of this star expands outward, producing a bow shock at a distance of 63 AU. Downstream of the bow, the termination shock reaches as far as 140 AU from the star.
This star has the third highest proper motion of any star visible to the unaided eye, after Groombridge 1830 and 61 Cygni, and the ninth highest overall. This motion will move the star into the constellation Tucana around 2640 AD. Epsilon Indi has a space velocity relative to the Sun of 86 km/s, which is unusually high for what is considered a young star. It is thought to be a member of the ε Indi moving group of at least sixteen population I stars. This is an association of stars that have similar space velocity vectors, and therefore most likely formed at the same time and location.
As seen from Epsilon Indi, the Sun is a 2nd-magnitude star in Ursa Major, near the bowl of the Big Dipper.
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