Search results
Results from the WOW.Com Content Network
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.
The nucleus of Comet Tempel 1. The nucleus is the solid, central part of a comet, formerly termed a dirty snowball or an icy dirtball. A cometary nucleus is composed of rock, dust, and frozen gases. When heated by the Sun, the gases sublime and produce an atmosphere surrounding the nucleus known as the coma.
While the solid nucleus of comets is generally less than 30 km across, the coma may be larger than the Sun, and ion tails have been observed to extend 3.8 astronomical units (570 Gm; 350 × 10 ^ 6 mi). [6] The Ulysses spacecraft made an unexpected pass through the tail of the comet C/2006 P1 (Comet McNaught), on February 3, 2007. [7]
The coma is generally made of ice and comet dust. [1] Water composes up to 90% of the volatiles that outflow from the nucleus when the comet is within 3–4 au (280–370 million mi; 450–600 million km) from the Sun. [1] The H 2 O parent molecule is destroyed primarily through photodissociation and to a much smaller extent photoionization. [1]
The comet’s next appearance may be in 80,000 years. ... Scientists were unsure if the comet — composed of ice, frozen gases and rocks — would survive its trip around our solar system’s ...
The passage of Earth through cosmic debris from comets and other sources is a recurring event in many cases. Comets can produce debris by water vapor drag, as demonstrated by Fred Whipple in 1951, [60] and by breakup. Each time a comet swings by the Sun in its orbit, some of its ice vaporizes and a certain amount of meteoroids are shed. The ...
These bodies, larger than 100 km to 1000 km, are called embryos or protoplanets. [9] In the current Solar System, these small bodies are usually also classified by dynamics and composition, and may have subsequently evolved [10] [11] [12] to become comets, Kuiper belt objects or trojan asteroids, for example.
The Halloween comet, C/2024 S1, was a member of the Kreutz family of comets, a population of mostly tiny comet fragments originating from a single parent object that fell apart near the sun ...