Halley's Comet returns to the vicinity of the Sun and Earth) about once every 76 years. Its last appearance was in 1986. What is the average distance from Halley's Comet to the Sun, given that the average distance from Earth to the Sun is 1.50 * 10¹¹ m? A) 6.4 * 10¹¹ m B) 1.8 *10¹² m C) 5.34 * 10⁶ m D) 1.1 * 10¹³ m E) 9.9 * 10¹³ m

Question

Quizplus · Accepted Answer

Halley's Comet has a very elliptical orbit, but on average its distance from the Sun is about 17.8 astronomical units (AU). One AU is the average distance from Earth to the Sun, which is given as 1.50 × 10^11 m in the problem. Therefore, the average distance from Halley's Comet to the Sun is:

17.8 AU × 1.50 × 10^11 m/AU = 5.34 × 10^12 m or 5.34 × 10^6 km

The correct answer is choice C, 5.34 × 10^12 m.

Halley's Comet Returns to the Vicinity of the Sun and Earth)