Epsilon Eridani

Ran is a star in the constellation Eridanus. It is located about 10.47 light years from Earth, being one of the closest to the solar system and the fourth closest visible to the naked eye. It is a main sequence star, of spectral type K2, very similar to the Sun, with a mass of 0.83 solar masses, a radius of 0.895 solar radii and a stellar luminosity of 0.28 times the solar luminosity.

Its optical spectrum is very variable, with many spectral emission lines. It has a very strong magnetic field that rotates approximately every 11 days. Its rotation period is 12 days. The reason for all this is its youth: it is only 600 million years old when our Sun is 4.6 billion years old.

Planetary system

It has an extrasolar planet orbiting around it, AEgir, discovered in 2000 by a team of astronomers led by Artie Hatzes. It has a mass of 1.2 ± 0.33 that of Jupiter and is at a distance of 3.3 AU from its star. Other observers, including Geoffrey Marcy, requested more information about the Doppler effect produced by the planet on the star, producing a large and varying magnetic field. Its existence had previously been suspected by a Canadian team led by Bruce Campbell and Walker Gordon in the early 1990s. In 2006, its existence was confirmed by the Hubble telescope. It spends 6.9 years in its orbit and rotates with a very eccentric orbit of e=0.702 that makes it approach the star up to 1.01 AU, something that happened in 2007, when the Hubble telescope was expected to photograph it, and it moves away. up to 5.77 AU.

It has two dust clouds, discovered in 1988 and 2004, at a distance similar to that of the asteroid belt and the Kuiper belt of the solar system, they are in the same plane as AEgir so Hubble is said to have confirmed that planets form from the dust disk. The disturbances in the cloud raise the suspicion of the existence of other new planets with a mass of 0.1 Jupiter mass and orbiting at 40 AU and 25 AU respectively, but which to date have not been confirmed.

Ran was the closest known star to Earth with a planet orbiting it, until in October 2012 the ESO announced the discovery of Alpha Centauri Bb.

In culture

Epsilon Eridani appears in the Foundations universe of the Russian-American writer Isaac Asimov. In the novel The Limits of the Foundation, Epsilon Eridani is home to the world called Comporellon, a planet on the brink of an ice age and which prides itself on being the first of the second wave of colonization from Earth, when it was baptized &# 34;World of Benbaly", an allusion to a mythical hero. However, in the Robot Novels cycle, the first colonial world is identified as Baleyworld or Bailey's World, by Bentley Bailey, son of Elijah Bailey, protagonist, with the robot R. Daneel Olivaw, of said saga.

In the Star Trek universe, Epsilon Eridani is also known as Delta Orcus or Toredar, an orange star around which the planet Axanar orbits, being located in the vicinity of 61 Ursae Majoris, Sirius and the Tau Ceti system.

Within the Halo saga, Epsilon Eridani has a system of eight planets (many of which are inhabited), among which is Reach, a UNSC military center considered the second fortress of humanity, a planet that was finally crystallized by the Covenant Particular Justice Fleet in the year 2552.

Also located in this system, on the third planet, is the Babylon 5 station from the series of the same name.