An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



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Number of Results: 142 Search : erg
mass-energy equivalence
  هموگ‌ارزی ِ جرم-کاروژ   
hamug-arzi-ye jerm-kâruž

Fr.: équivalence masse-énergie   

The principle of interconversion of mass and energy, described by the → mass-energy relation.

mass; → energy; → equivalence.

mass-energy relation
  باز‌آنش ِ جرم-کاروژ   
bâzâneš-e jerm-kâruž

Fr.: relation masse-énergie   

The famous equation proposed by Einstein as a consequence of his special theory of relativity describing the equivalence of mass and energy: E = mc2, where E is energy, m is the equivalent amount of mass, and c is the velocity of light.

mass; → energy; → relation.

mechanical energy
  کاروژ ِ مکانیکی   
kâruž-e mekâniki

Fr.: énergie mécanique   

The energy that is possessed by an object due to its motion or due to its position. It is equal to the sum of the → kinetic energy and → potential energy.

mechanical; → energy.

  ۱) تشکیدن؛ ۲) تشکاندن   
1) taškidan; 2) taškândan

Fr.: fusionner   

1) (v.intr.) To become combined, united, swallowed up, or absorbed; lose identity by uniting or blending.
2) ( To cause to combine or coalesce. To combine, blend, or unite gradually so as to blur the individuality or individual identity of.
Related terms: → fuse, → coalesce. See also → merger, → mergeburst, → merger process, → merger tree, → merging, → merging galaxy, → minor merger, → mixed merger, → wet merger.

From L. mergere "to dip, immerse," probably rhotacized from *mezgo, and cognate with Skt. majj- "to dive, to sink," majjati "dives under;" Lith. mazgoju "to wash."

Taškidan, taškândan, from Gilaki tašk "tie, knot;" Tabari tešk "knot" + -idan infinitive suffix.



A hypothetical → transient event undergone by a → star due to its violent → merging with another star in a → close binary star. The release of → orbital energy causes the → envelope of the star to heat up and → inflate, causing the star to brighten considerably. Mergebursts are predicted to rival or exceed the brightest classical → novae in luminosity, but to be much cooler and redder than classical novae, and to become slowly hotter and bluer as they age.

merge; → burst.

  ۱) تشکه؛ ۲) تشک   
1) tašké; 2) tašk

Fr.: fusion, coalescence   

1) Any combination of two or more bodies into a single body. In particular, the formation of a galaxy from the collision of two or more separate galaxies.
2) An act or instance of merging.

From → merge + -er (as in waiver).

Tašké; tašk, nouns from taškidan, → merge.

merger process
  فراروند ِ تشک   
farâravand-e tašk

Fr.: processus de fusion   

The process of collision between galaxies which leads to a single galaxy.

merger; → process.

merger tree
  درخت ِ تشک   
deraxt-e tašk

Fr.: arbre de coalescence   

A method used in → numerical simulations for studying the growth and development of galaxies and → dark matter halos. Within the currently accepted ΛCDM cosmology, dark matter halos merge from small → clumps to ever larger structures. This merging history can be traced in simulations and stored in the form of merger trees. Merger trees are necessary because a galaxy may have more than one → progenitor at an early time.

merger; → tree.


Fr.: 1) fusion   

1) (n.) The act of joining together as one, such as galaxy → merger.
2) (adj.) That merges.

Noun from → merge.

merging galaxies
  کهکشان‌های ِ تشکنده   
kahkešânhâ-ye taškandé

Fr.: galaxies en coalescence   

Two or more galaxies that collide and merge into one galaxy.

merging; → galaxy.

minor merger
  تشک ِ کهین   
tašk-e kehin

Fr.: fusion mineure   

The → merging in which one of the galaxies is significantly larger than the other (mass ratios above 10). The larger galaxy will often "swallow" the smaller satellite galaxy. The swallowed galaxy can trigger disk and nuclear star formation or activate a central core with shells that surround the predator.

minor; → merger.

mixed merger
  تشک ِ آمیخته   
tašk-e âmixté

Fr.: fusion mixte   

A merger that takes place when a → gas-poor galaxy collides with a → gas-rich galaxy.

Past-participle of → mix; → merger.

nuclear energy
  کاروژ ِ هسته‌ای   
kâruž-e haste-yi

Fr.: énergie nucléaire   

Energy released during a nuclear reaction as the result of the conversion of mass into energy. → mass-energy equivalence.

nuclear; → energy.

orbital energy
  کاروژِ مداری   
kâruž-e madâri

Fr.: énergie orbitale   

The → sum of the → potential energy and the → kinetic energy of an object in → orbit.

orbital; → energy.

pairing energy
  کاروژ ِ جفتش   
kâruž-e jofteš

Fr.: énergie de parité   

In nuclear physics, the extra binding energy associated with pairs of nucleons of the same kind. This quantity expresses the fact that nuclei with odd numbers of neutrons and protons have less energy and are less stable than those with even numbers of neutrons and protons.

Pairing, verbal noun of → pair; → energy.

periodically variable supergiant (PVSG)
  ابرغول ِ ورتنده‌ی ِ دوره‌ای   
abarqul-e vartande-ye dowreyi

Fr.: supergéante variable périodiquement   

A variable → supergiant star with typical periods of the order of 10 to 100 days and amplitudes less than a few tenths of a magnitude. PVSGs are thought to be pulsating → g modes, caused by a density inversion, arising from an → opacity bump, most likely from Fe, H, and/or He.

periodical; → -ly; → variable; → supergiant.

Planck energy
  کاروژ ِ پلانک   
kâruž-e Planck

Fr.: énergie de Planck   

The unit of energy in the system of Planck units. EP = √ (ħ c5/G) ≅ 1.22 x 1019 GeV. It can also be defined as EP = ħ / tP, where tP is the Planck time. This is an extraordinarily large amount of energy on the subatomic scale and particle accelerators have yet to produce a particle with this magnitude of energy. Understanding the properties of a subatomic particle that contains the Planck Energy is helpful in developing a Unified Field Theory which encompasses the realms of Quantum Theory and Relativity, although this too has evaded complete scientific understanding.

Planck; → energy.

potential energy
  کاروژ ِ توند   
kâruž-e tavand

Fr.: énergie potentielle   

Of a system, the work done in changing the system from some standard configuration to its present state. Thus, if a body of mass m is raised vertically through a height h, the work done, mgh, is the increase in potential energy.

potential; → energy.

potential energy curve
  خم ِ کاروژ ِ توند   
xam-e kâruž-e tavand

Fr.: courbe de l'energie potentielle   

A plot that displays the → potential energy of a moving body as a function of its position. It is explained by the → conservation of energy and the conversion of potential energy into → kinetic energy and vice versa.

potential; → energy; → curve.

radiant energy
  کاروژ ِ تابشی   
kâruž-e tâbeši

Fr.: énergie radiative   

The energy that is transmitted in the form of → radiation, in particular as → electromagnetic radiation.

radiant; → energy.

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