[18] This relative youth gives Epsilon Eridani a higher level of magnetic activity than the Sun, with a stellar wind 30 times as strong.

[34] Consequently, the Chinese name for ε Eridani itself is 天苑四 (Tiān Yuàn sì, the Fourth [Star] of Celestial Meadows.

The constellation Eridanus was named by Ptolemy – Ποταμού (Ancient Greek for 'River'), and Epsilon Eridani was listed as its thirteenth star.

[36][37] In 1598 Epsilon Eridani was included in Tycho Brahe's star catalogue, republished in 1627 by Johannes Kepler as part of his Rudolphine Tables.

The sequence number of Epsilon Eridani in the constellation Eridanus was 10, and it was designated Quae omnes quatuor antecedit (Latin for 'which precedes all four'); the meaning is the same as Ptolemy's description.

[note 3][48] In 1847, a new edition of Lalande's catalogue was published by Francis Baily, containing the majority of its observations, in which the stars were numbered in order of right ascension.

[53] Based on observations between 1800 and 1880, Epsilon Eridani was found to have a large proper motion across the celestial sphere, which was estimated at three arcseconds per year (angular velocity).

This process involves recording the position of Epsilon Eridani as Earth moves around the Sun, which allows a star's distance to be estimated.

[54] From 1881 to 1883, American astronomer William L. Elkin used a heliometer at the Royal Observatory at the Cape of Good Hope, South Africa, to compare the position of Epsilon Eridani with two nearby stars.

[64][65] From 1980 to 2000, a team of astronomers led by Artie P. Hatzes made radial velocity observations of Epsilon Eridani, measuring the Doppler shift of the star along the line of sight.

[68] Project Ozma, led by astronomer Frank Drake, used the Tatel Telescope to search for such signals from the nearby Sun-like stars Epsilon Eridani and Tau Ceti.

[68] Despite this lack of success, Epsilon Eridani made its way into science fiction literature and television shows for many years following news of Drake's initial experiment.

[72] Because of the proximity and Sun-like properties of Epsilon Eridani, in 1985 physicist and author Robert L. Forward considered the system as a plausible target for interstellar travel.

[26] Based on its nearby location, Epsilon Eridani was among the target stars for Project Phoenix, a 1995 microwave survey for signals from extraterrestrial intelligence.

[78] The apparent magnitude of 3.73 can make it difficult to observe from an urban area with the unaided eye, because the night skies over cities are obscured by light pollution.

[83] In Epsilon Eridani's chromosphere, a region of the outer atmosphere just above the light emitting photosphere, the abundance of iron is estimated at 74% of the Sun's value.

[85] Epsilon Eridani has a higher level of magnetic activity than the Sun, and thus the outer parts of its atmosphere (the chromosphere and corona) are more dynamic.

[66] Epsilon Eridani is classified as a BY Draconis variable because it has regions of higher magnetic activity that move into and out of the line of sight as it rotates.

[89][note 4] The axial tilt of Epsilon Eridani toward the line of sight from Earth is highly uncertain: estimates range from 24° to 72°.

[15] The high levels of chromospheric activity, strong magnetic field, and relatively fast rotation rate of Epsilon Eridani are characteristic of a young star.

[92] This anomaly might be caused by a diffusion process that has transported some of the heavier elements out of the photosphere and into a region below Epsilon Eridani's convection zone.

Observations with the James Clerk Maxwell Telescope (JCMT) at a wavelength of 850 μm show an extended flux of radiation out to an angular radius of 35 arcseconds around Epsilon Eridani, resolving the debris disc for the first time.

It would have required collisions between 11 Earth masses' worth of parent bodies to have maintained the disk in its current state over its estimated age.

Observations from NASA's Spitzer Space Telescope suggest that Epsilon Eridani actually has two asteroid belts and a cloud of exozodiacal dust.

One belt sits at approximately the same position as the one in the Solar System, orbiting at a distance of 3.00 ± 0.75 au from Epsilon Eridani, and consists of silicate grains with a diameter of 3 μm and a combined mass of about 1018 kg.

[111] The inner region around Epsilon Eridani, from a radius of 2.5 AU inward, appears to be clear of dust down to the detection limit of the 6.5 m MMT telescope.

Grains of dust in this region are efficiently removed by drag from the stellar wind, while the presence of a planetary system may also help keep this area clear of debris.

[108] Initially, the planet's mass was unknown, but a lower limit could be estimated based on the orbital displacement of Epsilon Eridani.

Only the component of the displacement along the line of sight to Earth was known, which yields a value for the formula m sin i, where m is the mass of the planet and i is the orbital inclination.

As Epsilon Eridani ages over a period of 20 billion years, the net luminosity will increase, causing this zone to slowly expand outward to about 0.6–1.4 au.