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

Post Reply New Topic

Polaris (aka Ursae Minoris, aka The North Star)
- Tripple star system
- Polaris A is a F7 super giant
- Third member discovered in 1929, orbiting Polaris A at a distance of only 18.5 AU.

Quaoar
– Properly called 50000 Quaoar, a trans-Neptunian object or a dwarf planet
– Discovered in 2002 by a CIT team of astronomers
– Estimate of diameter some 1250 km

Riegel
- The brightest star in the constellation of Orion
- The 6th brightest object in the sky
- About 850 ly from earth

Sirrah
– α Andromedae, also called Alpheratz
– sp. type A3 V (whitish yellow main-sequence star)
– parallax 33.60 mas

Titan
- Largest moon of Saturn (Second largest in the Solar System)
- The only moon in the solar system being able to maintain any substatial atmosphere.
- Surface pressure: about 1.5 times earth atmospheric pressure

Unukalhai
– α Serpentis
– sp. type K2 III (red giant star)
– parallax 44 mas

Venus

- planet

Whirlpool Galaxy (NGC 5194+5195)
– spiral galaxy in the constellation of Canes Venatici
– morphological type SA(s)bc pec
– app. visual magnitude V = 8.4

Xanthe (411 Xanthe)
- Main belt asteoroid
- 77 km in diameter
- Discovered 1896

Young
– Lunar crater
– Diameter 71 km
– Named after the scientist Thomas Young (1773–1829)

Zahringia (421 Zahringia)
- Main belt asteroid
- Discovered in 1896 by Max Wolf
- Orbits between 1.8 and 3.2 AU

Alcyone
– η Tauri
– Brightest star in the Pleiades cluster
– Sp. type B7 IIIe (bluish white giant)

Barnard's Star
- low mass red dwarf (M4Ve)
- about 6 ly from earth
- about 0.144 solar masses.

Caph
– β Cassiopeiae
– Sp. type F2 III-IV (yellowish subgiant or giant star)
– Parallax 59.58 mas

Deimos
- Outermost marsian moon
- Mean radius: 6 km
- Orbital period: 30 hours

Epsilon Eridani
- K-class orange dwarf
- Has one known planet (a gas supergiant) and a possible second (theorized as the method by which the two asteroid belts are maintained in their orbits)
- In Star Trek, the star system of the planet Vulcan, which is shown in the first movie as orbiting a gas giant

And revisiting a previous entry:

- retrograde rotation, such that if you could see the Sun from its surface, the Sun would rise in the west and set in the east
- covered with thick clouds of sulfur dioxide
- between atmospheric density, surface winds, surface temps, and composition of atmosphere, a hypothetical astronaut stepping out on the surface of Venus would be roughly simultaneously crushed by the pressure, shredded by the wind, broiled by the heat, and poisoned by the air. Not a nice place at all.