A-Z of astronomical objects (Stars, planets, galaxies etc.)

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Fomalhaut
- A-class, main sequence star
- Planetary system contains suspected Earth-like planet Formalhaut B (a few earth masses)
- Young star, only about 400-480 million years old

Ghost Head Nebula
– NGC 2080, emission nebula to the south of the Tarantula nebula
– Discovered by John F. W. Herschel in 1834
– Diameter ~50 ly across

Haumea
- TNO, host of 2 small moons
- Size: about 2000x1500x1000 km.
- White as newly fallen snow (albedo: 0.7)

Icarus (1566 Icarus)
– An Apollo asteroid, famous for its close approaches to Earth
– Measures 1.4 km across
– Discovered in 1949 by Walter Baade

Janus
- Small inner Saturn moon
- Coexists in the practically the same orbit as moon Epimetheus
- Orbits Saturn in an distance of about 150.000 km.

Kepler's Star
– Supernova in 1604
– No other supernovae have since been observed in the Milky Way
– Peak visual magnitude V ≈ –2.25

Lambda Serpentis
- star
- 38.34 lightyears distant
- G0V spectral class (Sol is G2V)

Menkib
– ζ Persei
– Sp. type B1 Ib (supergiant star)
– Radius some 30 times the Solar radius

(Note. Some authors identify the proper name Menkib with ξ Persei.)

Neptune:
- Eighth planet from the sun
- Atmospheric winds up to 1300 mph (2100 kph)
- Temperature at cloud tops approaches -218 degrees Centigrade (55 deg Kelvin); core temperature estimates run as high as 5000 degrees Centigrade (5400 deg Kelvin).

Oberon
- The second largest and outermost moon of Uranus
- Mean radius: about 760 km.
- Probably formed by the leftover disc of ice an rock left over from the formation of Uranus

Procyon
– α Canis Minoris
– Sp. type F5 IV-V (subgiant or dwarf star)
– Relatively close with parallax 285 mas

Qinghai (2255 Qinghai)
- main belt asteroid
- about 23 km in diameter
- named after the chinese province of Quinghai

Ring Nebula (M57, NGC 6720)
– Planetary nebula in Lyra
– App. dimensions 230" × 230"
– App. visual magnitude V = 8.8

Sedna
- Large TNO with at diameter of about 1000 km, with a highly eccentric orbit.
- The most distant of the discovered TNO's, 937 AU from the sun at aphelion.
- Consists mostly of water and methan ice.

Tegmeni
– ζ Cancri, actually a double binary system ζ¹+ζ² Cancri (both stars are binaries)
– Three spectra can be discerened, F7 V + F9 V + G0 V (three solar-type stars, the fourth is uncertain)
– Discovered to be a triple star by William Herschel in 1781, and only recently to be a quadruple star (there can be even more components)

Umbriel
- One of the five major moons of Uranus (27 in total)
- Because of the axial tit of Uranus, the polar regions of the moon experience 42 years of darkness, followed by
42 years of "daylight" (daylight equals to only 1/400 of the solar radiation hitting Earth)
- Radius: 585 km.