Epsilon Eridanus can be seen without a telescope. MAS in 2015 gave the name to a star in honor of the sea giantess named Ran. The Arabs called this star As-Sadir. Compared to the Sun, it has 28% luminosity, diameter and mass - 85%. It is believed that in the star system there can hardly be life. It is believed that a certain number of planets revolve around the star, but how many of them and what they are, could not be detected, because the star has great variability, as well as activity.
Observations
The star was watched a long time ago. For example, Claudius Ptolemy, a Greek astronomer from Alexandria, included a star in his catalog in the second century AD. It was also he who gave the name to the constellation, in ancient Greek, "Eridanus" means "river."
Many astronomical treatises of Eastern scholars in the Middle Ages were based precisely on the catalog presented by Ptolemy. Tycho Brahe also observed the star and included it in his catalog in 1598. Subsequently, Epsilon was included in other catalogs of various astronomers, many of them agreed that this body belongs to the third category of magnitude.
SETI
Philip Morrison and Giuseppe Kokkoni in 1960 made the assumption: what if extraterrestrial civilizations use radio signals to communicate? Astronomer Frank Drake used the Tagil telescope to find these signals from nearby stars: Epsilon Eridana and Tau Ceti. Neutral hydrogen was taken as the basis for the observation, or rather, the frequency of its study was 1420 MHz (21 cm). However, despite neither this experiment, nor subsequent ones, no signals were detected.
In 1977, William McLaughlin made such an assumption. In his opinion, some events that can be observed everywhere, for example, a supernova flash, can be used by aliens to synchronize signal reception and transmission. Although the National Observatory tested this assumption by observing the star for 15 days, no signals were received.
The properties
Since Epsilon Eridana is the closest star, she could be well studied. If you look at the constellation, you can see it in its northern part. According to the star classification system, Epsilon receives the K2 V class, it is an orange-red dwarf, and this is the second such closest star after beta Alpha Centauri. It was found that there is a lot of iron in the chromosphere, when compared with the Sun, then 74%.
This is how the artist represents the system.
In the presented video there is some more interesting information about the star.
The star has a very high magnetic activity, the chromosphere is quite dynamic. Compared with our luminary, the average magnetic field Epsilon is more than 40. On average it rotates around its own axis for 11 Earth days. The chromosphere has a rather high activity, the magnetic field is strong, the rotation speed is relatively fast - all these characteristics are just suitable for a young star.
It is believed that Epsilon is less than a billion years old, but not less than 200 and not more than 800 million. Dust can be seen around the star with a telescope, and it is also believed that this dust surrounds Epsilon in the same way as in the Solar System the Kuiper belt. It is also likely that there may be water ice in the belt.
Possible planets
There can be several planets near Epsilon. Scientists tried to find them repeatedly using the radial velocity method, but this turned out to be difficult due to stellar activity. Seeing the planets directly is not possible. When astronomers used infrared observations, they did not find planets with a body mass of Jupiter, although at least 1 should be.
Epsilon Eridana b was discovered in 2000, but the fact is still controversial. Astronomers around the world began research in 2008. Finally, it was announced that they had long suspected that a planet might be located there, but no specific confirmed data was ever presented. A program was launched at the La Silla observatory to search for the planet, but nothing was confirmed.
However, there are parameters that define the planet. It is believed that its orbital period is approximately 6.85 years. The mass is still unknown, but it is estimated in relation to Epsilon Eridan. Also, they still cannot determine the eccentricity of the orbit. Some astronomers are sure that this value is 0.7. However, the asteroid belt should be nearby, and then this value is incompatible. This is what the proposed planet should look like.
In addition to B, there is also C. A computer simulated a dust disk that revolves around Epsilon. At the same time, it was suggested that the old planet is nearby, possibly at a distance of 40 AU. However, how the planet was created at such a distance was not explained. Perhaps the disk will disperse, after which a large planet will form, or it may migrate.
Mention in art
It has already been indicated above that the star is the closest to the Sun, which very often science fiction authors mention it in their writings.
So, for example, if you read Isaac Asimov, then in his novels about the robot you can see a mention about Epsilon Eridan. Baron - a science fiction and biochemist - wrote a work of the same name, in which the main action takes place on this planet.
Sergey Tarmashev also mentioned Epsilon in his cycle called "Ancient".
If you watched Star Trek, the planet Volcano where Mr. Spock was born is often mentioned there. Fans believe that the action takes place on Epsilon.
In the Halo series of games in the Epsilon system, there is a planet called Reach, where the navy is located.
Also, the star was mentioned in the game "Face of Mankind2", where an ice planet revolves around it, on which the space colony is located.