What is Halley's Comet?
Q: What is Halley's Comet?
A: Halley's Comet is a comet that orbits the sun and comes around every 75 or 76 years.
Q: When is Halley's Comet expected to return?
A: Halley's Comet is expected to return in 2061.
Q: Who is Edmond Halley?
A: Edmond Halley was an English astronomer who predicted the return of Halley's Comet.
Q: What is the definition of "periodic"?
A: "Periodic" means that something occurs regularly.
Q: How was Halley's Comet observed in detail in 1986?
A: Halley's Comet was observed in detail by spacecraft that visited it in 1986.
Q: What did these observations reveal about Halley's Comet?
A: These observations revealed that Halley's Comet was composed of a mixture of volatile ices and dust, which supported Fred Whipple's "dirty snowball" model.
Q: What is the surface of Halley's Comet mostly composed of?
A: The surface of Halley's Comet is mostly composed of dusty, non-volatile materials, with only a small portion being icy.
