Figure 2-14 Halley’s Comet Halley’s Comet orbits the Sun with an average period of about 76 years. During the twentieth century, the comet passed near the Sun twice—once in 1910 and again, as shown here, in 1986. The comet will pass close to the Sun again in 2061. During its last visit, the comet spread more than 5° across the sky, or 10 times the diameter of the Moon.