N Centauri [SEP] constellation
N Centauri
N Centauri (N Cen) is a double star in the constellation Centaurus. It is approximately 260 light years from Earth.
The more luminous star is a blue-white B-type main sequence dwarf with an apparent magnitude of +5.26. Its fainter companion is a yellow-white F-type dwarf with an apparent magnitude of +7.72. The two stars show common proper motion, indicating they may be gravitationally bound. They are separated by 18 arcseconds.
under six light-years, Barnard's Star is the nearest-known star in the constellation Ophiuchus, and the fourth-closest known individual star to the Sun, after the three components of the Alpha Centauri system. In 1916, Barnard's Star was discovered by American astronomer Edward Emerson Barnard, whom the star was named after.
1916 Covalent bonding
- The idea of covalent bonding can be traced several years to Gilbert N. Lewis, who in 1916 described the sharing of electron pairs between atoms. He introduced the