2025年1月14日 · Comets are large objects made of dust and ice that orbit the Sun. Best known for their long, streaming tails, these ancient objects are leftovers from the formation of the solar system 4.6 billion years ago.

2024年12月9日 · Comets are frozen leftovers from the formation of the solar system composed of dust, rock, and ices. They range from a few miles to tens of miles wide, but as they orbit closer to the Sun, they heat up and spew gases and dust into a …

A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or coma surrounding the nucleus, and sometimes a tail of gas and dust gas blown out from the coma.

2025年2月16日 · Comet, a small body orbiting the Sun with a substantial fraction of its composition made up of volatile ices. Comets are among the most-spectacular objects in the sky, with their bright glowing comae and their long tails.

2023年7月31日 · Comets are defined as icy bodies of frozen gases, rocks and dust left over from the formation of the solar system about 4.6 billion years ago. They orbit the sun in highly …

2024年11月28日 · Comets are icy balls of gas, dust and rock that orbit the sun. Astronomers believe most comets are leftovers from the formation of the sun and planets. In fact, comets come...

2000年6月7日 · What Are Comets? * Comets are small, fragile, irregularly shaped bodies composed of a mixture of grains and frozen gases. They have highly elliptical orbits that repeatedly bring them very close to the Sun and then swing them deeply into space, often beyond the orbit of Pluto.

2025年1月24日 · A comet is a space object of ice and dust that orbits the Sun. When a comet is in the inner Solar System, it can be seen in the sky as a blurry spot with a tail. What are comets made of?

What is a Comet? A comet is a very small solar system body made mostly of ices mixed with smaller amounts of dust and rock. Most comets are no larger than a few kilometres across. …

2023年10月16日 · What exactly is a comet? Comets are leftover material from the formation of the solar system. As the solar system formed about 4.5 billion years ago, most gas, dust, rock …