Definitions for comets
comets

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1. Comets

   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. These phenomena are due to the effects of solar radiation and the outstreaming solar wind plasma acting upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit. If sufficiently close and bright, a comet may be seen from Earth without the aid of a telescope and can subtend an arc of up to 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures and religions. Comets usually have highly eccentric elliptical orbits, and they have a wide range of orbital periods, ranging from several years to potentially several millions of years. Short-period comets originate in the Kuiper belt or its associated scattered disc, which lie beyond the orbit of Neptune. Long-period comets are thought to originate in the Oort cloud, a spherical cloud of icy bodies extending from outside the Kuiper belt to halfway to the nearest star. Long-period comets are set in motion towards the Sun by gravitational perturbations from passing stars and the galactic tide. Hyperbolic comets may pass once through the inner Solar System before being flung to interstellar space. The appearance of a comet is called an apparition. Extinct comets that have passed close to the Sun many times have lost nearly all of their volatile ices and dust and may come to resemble small asteroids. Asteroids are thought to have a different origin from comets, having formed inside the orbit of Jupiter rather than in the outer Solar System. However, the discovery of main-belt comets and active centaur minor planets has blurred the distinction between asteroids and comets. In the early 21st century, the discovery of some minor bodies with long-period comet orbits, but characteristics of inner solar system asteroids, were called Manx comets. They are still classified as comets, such as C/2014 S3 (PANSTARRS). Twenty-seven Manx comets were found from 2013 to 2017.As of November 2021 there are 4,584 known comets. However, this represents a very small fraction of the total potential comet population, as the reservoir of comet-like bodies in the outer Solar System (in the Oort cloud) is about one trillion. Roughly one comet per year is visible to the naked eye, though many of those are faint and unspectacular. Particularly bright examples are called "great comets". Comets have been visited by unmanned probes such as the European Space Agency's Rosetta, which became the first to land a robotic spacecraft on a comet, and NASA's Deep Impact, which blasted a crater on Comet Tempel 1 to study its interior.

Anagrams for comets »

1. comest

How to pronounce comets?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

   Indian

   Zira

   US English

   Oliver

   British

   Wendy

   British

   Fred

   US English

   Tessa

   South African

How to say comets in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of comets in Chaldean Numerology is: 8

2. Pythagorean Numerology

   The numerical value of comets in Pythagorean Numerology is: 3

Examples of comets in a Sentence

1. Darryl Seligman:

   The comets and asteroids in the solar system have arguably taught us more about planet formation than what we’ve learned from the actual planets in the solar system, i think that the interstellar comets could arguably tell us more about extrasolar planets than the extrasolar planets we are trying to get measurements of today.

2. Martin Cordiner:

   This shows that 2I/Borisov is not a completely alien object, and confirms some similarity with our 'normal' comets, so the processes that shaped it are comparable to the way our own comets formed.

3. Matthew Knight:

   We have tried to avoid putting it in one of those boxes and prefer to call it more generically an 'object,' in simple terms, asteroids are rocky and devoid of ices, while comets are a mixture of rock and ice, so-called 'dirty snowballs,'.

4. Michal Drahus:

   We immediately noticed the familiar coma and tail that were not seen around Oumuamua, this is really cool because it means that our new visitor is one of these mythical and never-before-seen real interstellar comets.

5. Professor Lattanzio:

   These include the detection of biologically relevant molecules in interstellar clouds and comets, mid-infrared spectra of interstellar grains and the dust from comets, a diverse set of data from comets including the Rosetta mission showing consistency with biology and the frequency of Earth-like or habitable planets in the Galaxy.

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References

1. ^ Wikipedia
   https://en.wikipedia.org/wiki/Comets