When we observe the stars in the sky, the seemingly single dots of light can be deceiving. In fact, more than four-fifths of lights we see in the sky are star systems consisting of two or more stars. When two stars orbit a common central mass they are classified as binary stars. Generally speaking, there is usually a primary brighter star and dimmer secondary star in any given binary system. There are also different classifications of binary stars based on their orbits; wide binaries are binary stars that are relatively far from each other and that do not have a great effect on their companions. Close binaries, however, evolve within a close proximity and are able to “transfer their mass from one to the other” (SPACE.com). It has been suggested that the sun is part of a binary star system, yet a study done by NASA in 2010 revealed no companion star to our sun.
Recently the Hubble Telescope was able to observe a remnant of a Type Ia supernova in the Large Magellanic Cloud. A Type Ia supernova is believed to occur only in a binary system where at least one of the stars has become a white dwarf. Two theories exist that attempt to explain such a supernova. The first requires both stars in the binary system to be white dwarfs; if the two stars collide and combine the theory suggests a Type Ia supernova would occur. The second theory is slightly more complex and only requires one of the stars in the system to be a white dwarf. This theory states that white dwarf star would extract material from the companion star until a fusion reaction occurred that would trigger a supernova of Type Ia. In this case the companion star has the possibility of survival, however, no evidence has been found to support this theory until possibly now. Astronomers hoped to find a surviving star near the center of the explosion, the discovery of “surviving companion would put an end to the ongoing discussion about the origin of Type Ia supernova” (sci-news.com).
Although a star has been found in that area, meeting the criteria of a surviving companion star, further investigation is needed to produce a definitive confirmation.