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Betelgeuse’s distance was initially measured by the parallax effect it had on Earth. Two observations, taken on either end of Earth’s orbit, would subtend an angle that can yield the distance. It started in 1920, when the first interferometric studies were performed, the star’s distance equated to 180 light-years. A lot of other measurements have estimated its distance to be as high as 1300 light-years. In the 1990s there were two conflicting measurements. One, where the parallax was determined to be π=9.8±4.7 mas and the other, where the parallax was determined to be π=5±4 mas . The first one suggested a distance of 330 light-years; whereas, the second one suggested a distance of 650 light-years. In 2008, the VLA[1] produced a solution of 643±146 ly ; although this value has a 22% error, the accepted distance is approximately 642 light-years.