An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 902
apparent distance
  دورا‌ی ِ پدیدار   
durâ-ye padidâr

Fr.: distance apparente   

The angular distance between two celestial bodies (e.g. the components of a binary star system), expressed in degrees, minutes and seconds of arc.

apparent; → distance.

apparent field
  میدان ِ پدیدار   
meydân-e padidâr

Fr.: champ apparent   

The angular diameter of the circle of light that the eye sees through an eyepiece.

apparent; → field.

apparent horizon
  افق ِ پدیدار   
ofoq-e padidâr

Fr.: horizon apparent   

The circle determined by the intersection of the heavens with a → cone whose → vertex is the → eye, and whose elements are tangent to lines of the Earth's surface. Same as → visible horizon. Assuming that there is no → atmospheric refraction, apparent horizon coincides with → geometric horizon. See also → sea horizon.

apparent; → horizon.

apparent magnitude
  برز ِ پدیدار   
borz-e padidâr

Fr.: magnitude apparente   

A measure of a star's observed brightness (opposed to → absolute magnitude); symbol m. It depends on the star's → intrinsic brightness, its distance from the observer, and the amount of → interstellar absorption. The brightest star → Sirius has an apparent magnitude of -1.46, while the weakest stars visible with the naked eye in the most favorable observation conditions have magnitudes of about +6.5. The stars of magnitudes less than +23 are measured by professional observatories, whereas those of magnitudes less than +30 by a telescope such as the → Hubble Space Telescope (M.S.: SDE).

apparent; → magnitude.

apparent noon
  نیمروز ِ پدیدار   
nimruz-e padidâr

Fr.: midi vrai   

The moment when the center of the Sun crosses the meridian. Same as true noon.

apparent; → noon.

apparent place
  جای ِ پدیدار   
jâ-ye padidâr

Fr.: position apparente   

Same as → apparent position.

apparent; → place.

apparent position
  نهش ِ پدیدار، جا‌ی ~   
naheš-e padidâr, jâ-ye ~

Fr.: position apparente   

1) The position on the celestial sphere at which a heavenly body would be seen from the Earth at a particular time.
2) A position given by the coordinates calculated for a star, if it were seen from the Earth's centre, relative to the → real equator and the → real equinox, at a certain date. It includes the displacements from one heliocentric direction, given in a stellar catalogue, due to → precession, → nutation, → aberration, → proper motions, → annual parallax, and light gravitational deviation (M.S.: SDE).

apparent; → position.

apparent rising
  بر‌آیش ِ پدیدار   
barâyeš-e padidâr

Fr.: lever apparent   

The instant of time when the object is in the East and the geometric → zenith distance is equal to 90° plus the → horizontal refraction plus the semidiameter minus the → parallax.

apparent; → rising.

apparent setting
  فروشد ِ پدیدار   
forušod-e padidâr

Fr.: coucher apparent   

The instant of time when the object is in the West and the geometric → zenith distance is equal to 90° plus the → horizontal refraction plus the semidiameter minus the → parallax.

apparent; → setting.

apparent sidereal day
  روز ِ اختری ِ پدیدار   
ruz-e axtari-ye padidâr

Fr.: jour sidéral apparent   

The time interval between two successive → upper transits of the → true equinox of date.

apparent; → sidereal; → day.

apparent sidereal time
  زمان ِ اختری ِ پدیدار   
zamân-e axtari-ye padidâr

Fr.: temps sidéral apparent   

The → mean sidereal time corrected for the → nutation and shift in the obliquity of the ecliptic that occurs as a result of the Moon's gravitational effect. Apparent sidereal time differs from mean sidereal time in that the → true vernal equinox point is used.

apparent; → sidereal; → time.

apparent solar day
  روز ِ خورشیدی ِ پدیدار   
ruz-e xoršidi-ye padidâr

Fr.: jour solaire vrai   

The duration of one rotation of the Earth on its axis (→ Earth's rotation), with respect to the → apparent Sun. It is measured by successive transits of the apparent Sun over the lower branch of a → meridian.

apparent; → solar day.

apparent solar time
  زمان ِ خورشیدی ِ پدیدار   
zamân-e xoršidi-ye padidâr

Fr.: temps solaire apparent   

The time based on the motion of the → apparent Sun and kept by dividing the day into 24 equal hours.

apparent; → solar; → time.

apparent Sun
  خورشید ِ پدیدار   
xoršid-e padidâr

Fr.: Soleil apparent   

The → true Sun as seen by an observer on Earth. The term "apparent Sun" is used in contrast to → mean Sun, which refers to an average of the Sun's position). See also: → apparent solar time and → mean solar time.

apparent; → Sun.

apparent visual magnitude
  برز ِ دیدگانی ِ پدیدار   
borz-e didegâni-ye padidâr

Fr.: magnitude visuelle apparente   

Apparent magnitude in the visual wavelengths, around 5600 Å. → visual magnitude.

apparent; → visual; → magnitude.

apparition
  پدیداری، پدیدارش   
padidâri (#), padidâreš

Fr.: apparition   

A period during which a → planet, → asteroid, or → comet is observable, generally between two successive → conjunctions of the body with the Sun.

M.E. apparicioun, from O.Fr. apparition, from L.L. appritionem "an appearance," from L. apparitus, p.p. of apparere "to appear."

Padidâri, n. from → padidâr + -i; padidâreš, verbal n. from *padidâridan.

apperception
  بر‌آگرتش   
barâgerteš

Fr.: aperception   

In psychology of education, the fundamental process in acquiring knowledge, and the part played by existing knowledge.

From Fr. aperception, from N.L. apperceptionem, from ap- variant of → ad- before p + → perception.

From prefix bar- "on, upon, up" (Mid.Pers. abar; O.Pers. upariy "above; over, upon, according to;" Av. upairi "above, over," upairi.zəma- "located above the earth;" cf. Gk. hyper- "over, above;" L. super-; O.H.G. ubir "over;" PIE base *uper "over") + âgerteš, → perception.

application
  آتاهش، کاربرد   
âtâheš, kârbord (#)

Fr.: application   

1) General: The act of applying to a particular purpose or use.
2) Computers: A program that performs a specific function for the user, as contrasted with an environment or operating system. Some examples are Microsoft Windows, Microsoft Word, and Adobe Photoshop. The word "application" is used because each program has a specific application for the user.

Verbal noun of → apply.

application software
  نرم‌افزار ِ آتاهشی   
narm-afzâr-e âtâheši

Fr.: logiciel d'application   

A software with a specific function, such as a word processor or game. Contrast with operating system software.

application; → software.

applied physics
  فیزیک ِ کاربردی   
fizik-e kârbordi (#)

Fr.: physique appliquée   

A set of topics in physics intended for a particular or practical use. Applied physics programs are usually interfaces between pure physics and technology.

Past participle of → apply; → physics.

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