About the Book
Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Pages: 29. Chapters: Epsilon Eridani, Achernar, List of stars in Eridanus, X-rays from Eridanus, 40 Eridani, CMB cold spot, P Eridani, Theta Eridani, Orion-Eridanus Superbubble, Gliese 86, 82 G. Eridani, HD 28185, HD 28185 b, Beta Eridani, Eridanus Group, Eridanus Cluster, Epsilon Eridani b, HD 10647, HR 1614, Delta Eridani, NGC 1300, Upsilon Eridani, 58 Eridani, NGC 1309, NGC 1232, Gliese 86 b, EF Eridani, HD 30562, GRB 080913, Tau Eridani, DEN 0255-4700, HIP 12961, NGC 1532, 2MASS 0415-0935, HR 857, NGC 1427A, HD 30562 b, HD 10647 b, Gamma Eridani, Tau2 Eridani, NGC 1531, Horologium Supercluster, Omicron Eridani, NGC 1234, Tau4 Eridani, NGC 1291, NGC 1637, 53 Eridani, 14 Eridani, NGC 1535. Excerpt: Epsilon Eridani ( Eri, Eridani) is a star in the constellation Eridanus. At a distance of 10.5 light years (ly), it has an apparent magnitude of 3.73. It is the third closest of the individual stars or star systems visible to the naked eye and is the closest known star that hosts an orbiting planet. Its age is estimated at less than a billion years. Because of its youth, Epsilon Eridani has a higher level of magnetic activity than the present-day Sun, with a stellar wind 30 times as strong. Its rotation period is a relatively rapid 11.2 days at the equator. Epsilon Eridani is both smaller and less massive than the Sun, and has a comparatively lower level of the elements heavier than helium. Astronomers categorize it as a main-sequence star of spectral class K2, which means the energy being generated at the core through nuclear fusion of hydrogen is emitted from the surface at a temperature of about 5,000 K, giving the star an orange hue. The motion of this star along the line of sight to the Earth, its radial velocity, has been regularly observed for more than twenty years. Periodic changes in this data yield evidence of a giant...
