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What distance did Friedrich Bessel find for 61 Cygni using parallax?

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Diagram illustrating how astronomers calculate the distance to a star using parallax: Earth is shown in two positions on opposite sides of its orbit around the Sun, with lines extending to a nearby star X and further to distant background stars. The apparent shift in star X's position, measured as angle A, is used to determine its distance, with the baseline labeled as 186,000,000 miles. — Parallax Calculating stellar distances.

In 1838, German astronomer Friedrich Wilhelm Bessel successfully measured the parallax of the star 61 Cygni. He determined a parallax of approximately one-third of a second of arc, which corresponds to a distance of about 10.3 light-years from Earth.123

While Bessel was the first to accurately demonstrate this annual parallax, it is important to note that he did not express his findings in terms of light-years at the time. Modern measurements, such as those from the Hipparcos satellite, have since refined this distance to approximately 11.4 light-years.231