perihelion

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perihelion

(pĕr'əhē`lēən), point nearest the sun in the orbit of a body about the sun. See apsisapsis
(pl. apsides), point in the orbit of a body where the body is neither approaching nor receding from another body about which it revolves. Any elliptical orbit has two apsides.
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perihelion

(pe-ră-hee -kee-ŏn) The point in the orbit of a planet, comet, or artificial satellite in solar orbit that is nearest the Sun. The Earth is at perihelion on or about Jan. 3. The time of year at which Earth reaches perihelion varies over a period of about 20 000 years, getting progressively later in the year. The perihelion distance q , and aphelion distance Q , of major planets and asteroids are given in Tables 1 and 3, backmatter. See also advance of the perihelion.

Perihelion

(religion, spiritualism, and occult)

Although they approximate circles, every orbit is elliptical. The point in a satellite’s orbit when it is nearest the Sun is called its perihelion (from the Greek peri, meaning “near” and helios, meaning “sun”).

Perihelion

 

the point nearest the sun in the orbit of a celestial body moving around the sun in a conic section—an ellipse, parabola, or hyperbola. Because of perturbations caused by the planets, perihelion positions change. For the planet closest to the sun, Mercury, a perihelion shift has been detected that arises in accordance with the more precise law of gravitation that follows from the general theory of relativity. The distance from perihelion to the center of the sun is called the perihelion distance.

perihelion

[¦per·ə¦hēl·yən]
(astronomy)
That orbital point nearest the sun when the sun is the center of attraction.

perihelion

The point in the orbit of a planet or a comet where it is nearest to the sun. The earth is at perihelion about January 1, when it is 3.4%, or about 3 million miles nearer to the sun than about July 1, when it is at aphelion—the point farthest from the sun. See aphelion.

perihelion

the point in its orbit when a planet or comet is nearest the sun
References in periodicals archive ?
With about 20 times as many Kuiper belt objects in hand, astronomers should be able to see if there are more objects with bizarre orbits and determine if the bunching of perihelia is real or just an artifact of having found only a few.
These 10 known extreme Kuiper Belt objects could have formed in a similar manner to Sedna and 2012 [VP.sub.113], but past interactions with Neptune are also a possibility, as the perihelia of these objects are more within Neptune's reach.
The Earth and Sun came a little closer during each of the last 50 years except 1992, so this is one of the "mildest" perihelia ever.
The comet's 6.9-year period resulted in perihelia occurring about one month earlier at each return.