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

The time interval of 27.554 551 days (27d 13h 18m 33.2s), on average, between two successive passages of the Moon through the → perigee of its orbit.

Anomalistic from → anomaly.

Pirâzamini from pirâzamin, → perigee.

Anomalistic from → anomaly.

Pirâhuri from pirâhur, → perihelion.

Of or relating to → ballistics.

A missile that after being launched and guided in the early part of its flight, travels unpowered in a ballistic trajectory.

→ ballistic; → missile.

Transfer of microbes and biochemical compounds from a planet to another due to meteoric impacts. Debris being knocked off a planet like Mars can reach escape velocity and enter the atmosphere of another planet with passenger micro-organisms intact.

→ ballistic; → panspermia.

A curved path followed by an unpowered object that is being acted upon only by gravitational forces and the friction of the medium through which it moves.

→ ballistic; → trajectory.

Audible disturbance or wave caused by the compression of air ahead of a projectile in flight.

→ ballistic; → wave.

The science of the motion and behavior of → projectiles. The study of the functioning of firearms.

From L. ballista "ancient military machine for hurling stones," from Gk. ballistes, from ballein "to throw," from PIE *g^welH₁- "to throw;" cf. Pers. garzin "arrow;" Av. niγr- "to throw down;" Khotanese (+ *abi-, *ui-) bīr- "to throw, sow;" Proto-Iranian *garH- "to throw."

Partâbik, from partâb "a throw, an arrow that flies far," partâbidan "to throw," + -ik, → -ics; partâbšenâsi, from partâb + -šenâsi, → -logy.

A small cyst on the skin, containing watery liquid, as from a burn or other injury.

M.E. blister, blester, from O.Fr. blestre, of Germanic origin.

Tâval "blister" (variants Torbet-Heydariye-yi toval, Guqari tavol), from suffixed (-al) tâv- tav, taf- "to heat, burn, shine," variant of tâb-, tâbidan "to shine," → luminous.

A model according to which an → H II region is a hot mass of ionized gas located on the surface of a → molecular cloud, like a blister on the body skin.

→ blister; → model.

The eighth of → Jupiter's known moons and the second brightest and the outermost of the four → Galilean satellites. With a diameter of 4800 km (0.38 Earths), Castillo is roughly the same size as Mercury. It orbits Jupiter in 16.689 days at a distance of 1,883,000 km from the planet, beyond Jupiter's main → radiation belts. It is the third largest moon in the entire solar system. Its mass is 10.76 × 10²² kg (about 1.5 Earth Moons) and its mean → surface temperature is -155 °C. The most prominent feature of Callisto is its craters, as it has the most craters of any object in the solar system. Due to its orbit being further away from Jupiter, it is not under the same → tidal heating influences as → Io, → Europa, or → Ganymede. Callisto's thin → atmosphere is composed of → carbon dioxide and likely some → molecular oxygen. Callisto is thought to have formed as a result of slow → accretion from the → protoplanetary disk of gas and dust that surrounded Jupiter after its formation.

Callisto, an attendant of Artemis in Greek mythology. Because of her love affair with Zeus, she was transformed into a bear by Artemis. According to another legend she was changed into a bear by the jealous Hera. Zeus transferred her to the heavens as the → constellation  → Ursa Major (great bear).

An advocate of → existentialism.

→ existential; → -ist.

1) A person who shows great independence or individuality in thought or action (Dictionary.com).
2) An advocate of → individualism (Dictionary.com).

→ individual; → -ist.

An astronomer, engineer, or technician who is concerned with the construction of astronomical instruments.

→ instrumental + → -ist.

1a) A series of names or other items written or printed together in a meaningful grouping or sequence so as to constitute a record.
1b) Computers: A series of records in a file.
2) To set down together in a list; make a list of (Dictionary.com).

From M.E. liste "border, edging, stripe," from O.Fr. liste "border, band, row," also "strip of paper," or from O.It. lista "border, strip of paper, list," both from Germanic sources (compare O.H.G. lista "strip, border, list," O.Norse lista "border."

List, loan from Fr. liste, as above.

1) A list; the act of compiling a list; something listed.
2) Computers: A display or printed list of lines in a program or digital data.

→ list; → -ing.

1) A person who tends to view or represent things as they really are; an adherent of → realism.
2) Of or pertaining to realism or to a person who embodies its principles or practices.

→ real; → -ist.

1) Interested in, concerned with, or based on what is real or practical.
2) Philo.: Of or pertaining to realists or → realism.

From → real + -istic, from L. -isticus, Gk. -istikos, from -ikos, → -ic.