An Etymological Dictionary of Astronomy and Astrophysics

A conspicuous band of molecular → CH (methylidine) at 4300 Å, which is present in the spectra of late-type G-K stars.

See also: G refers to → G type stars in the spectra of which this feature is strong. → band.

A conspicuous band of molecular → CH (methylidine) at 4300 Å, which is present in the spectra of late-type G-K stars.

See also: G refers to → G type stars in the spectra of which this feature is strong. → band.

Waves trapped inside stars, whose restoring force is the → buoyancy. Same as → gravity mode. See also: → oscillation modes;
→ p mode; → f mode.

See also: g referring to gravity; → mode.

Waves trapped inside stars, whose restoring force is the → buoyancy. Same as → gravity mode. See also: → oscillation modes;
→ p mode; → f mode.

See also: g referring to gravity; → mode.

The → Saturn’s ring, with a width of 8,000 km, lying before the → F ring, at 164,000-172,000 km from the center of Saturn.

See also: → ring.

The → Saturn’s ring, with a width of 8,000 km, lying before the → F ring, at 164,000-172,000 km from the center of Saturn.

See also: → ring.

A member of a class of stars to which the Sun belongs. The G-type stars on the → main sequence have → surface temperatures of 5,300-6,000 K and therefore appear yellow in color. G type → giant stars (such as → Capella) are almost 100-500 K colder than the corresponding main sequence stars.
G type → supergiants have temperatures of 4,500-5,500 K. The spectrum of early type G stars, such as the Sun (G2), is dominated by ionized lines of calcium (→ H and K lines, mainly) and neutral metals. In later type G stars the molecular bands of → CH molecules
and → CN molecules become visible. The main sequence and giant
stars have masses of ~ 1 solar mass, while the supergiants are of ~ 10 solar masses. The luminosities of G-type giants are almost 30-60 times greater than that of the Sun, whereas the supergiants are 10,000-30,000 times more luminous.

See also: G, from the → Harvard classification; → star.

A member of a class of stars to which the Sun belongs. The G-type stars on the → main sequence have → surface temperatures of 5,300-6,000 K and therefore appear yellow in color. G type → giant stars (such as → Capella) are almost 100-500 K colder than the corresponding main sequence stars.
G type → supergiants have temperatures of 4,500-5,500 K. The spectrum of early type G stars, such as the Sun (G2), is dominated by ionized lines of calcium (→ H and K lines, mainly) and neutral metals. In later type G stars the molecular bands of → CH molecules
and → CN molecules become visible. The main sequence and giant
stars have masses of ~ 1 solar mass, while the supergiants are of ~ 10 solar masses. The luminosities of G-type giants are almost 30-60 times greater than that of the Sun, whereas the supergiants are 10,000-30,000 times more luminous.

See also: G, from the → Harvard classification; → star.

A yellowish star whose surface temperature is about 6000 K and its spectrum is dominated by H and K lines of ionized calcium (Ca II 3968 Å and 3934 Å).

See also: G from the alphabetical sequence of spectral types; → type;
→ star.

A yellowish star whose surface temperature is about 6000 K and its spectrum is dominated by H and K lines of ionized calcium (Ca II 3968 Å and 3934 Å).

See also: G from the alphabetical sequence of spectral types; → type;
→ star.

A relatively uncommon → carbonaceous carbonaceous asteroid whose spectrum contains a strong → ultraviolet  → absorption feature below 0.5 μm (→ Tholen classification). In the → SMASS classification it corresponds to the Cg and Chg types , depending on the presence or absence (respectively) of the absorption feature at 0.7 μm. The most remarkable “asteroid” in this type is → Ceres (now classified as a → dwarf planet).

See also: → type; → asteroid.

A relatively uncommon → carbonaceous carbonaceous asteroid whose spectrum contains a strong → ultraviolet  → absorption feature below 0.5 μm (→ Tholen classification). In the → SMASS classification it corresponds to the Cg and Chg types , depending on the presence or absence (respectively) of the absorption feature at 0.7 μm. The most remarkable “asteroid” in this type is → Ceres (now classified as a → dwarf planet).

See also: → type; → asteroid.

Same as → G star.

See also: → G star; → type.

Same as → G star.

See also: → G star; → type.