EVENING STAR

Venus, also known as the Evening Star or the Morning Star, depending on its position in the sky and its relationship to setting or rising sun. As one of the brightest objects in the sky, Venus has been a major fixture in human culture for as long as records have existed. It has been made sacred to gods of many cultures, and has been a prime inspiration for writers and poets. Venus was the first planet to have its motions plotted across the sky, as early as the second millennium BC, and was a prime target for early interplanetary exploration as the closest planet to Earth (as much as 261 million kilometres far - that's very far!).

It was the first planet beyond Earth visited by a spacecraft (Mariner 2) in 1962, and the first to be successfully landed on (by Venera 7) in 1970. Venus's thick clouds render observation of its surface impossible in visible light, and the first detailed maps did not emerge until the arrival of the Magellan orbiter in 1991. Plans have been proposed for rovers or more complex missions, but they are hindered by Venus's extremely hostile surface conditions, exacerbated by a runaway greenhouse gas effect that have raised surface temperatures enough to melt lead metal.

This post is part of the Skywatch Friday meme.

SOUTHERN CROSS

Crux is a constellation located in the southern sky in a bright portion of the Milky Way. It is among the most easily distinguished constellations, as all of its four main stars have an apparent visual magnitude above +2.8, even though it is the smallest of all 88 modern constellations.

Its name is Latin for 'cross', and it is dominated by a cross-shaped or kite-like asterism that is sometimes known as the Southern Cross. Predominating is the first-magnitude blue-white star of Alpha Crucis or Acrux, being the constellation's brightest and most southerly member. Crux is followed by four dominate stars, descending in clockwise order by magnitude: Beta, Gamma (one of the closest red giants to Earth), Delta and Epsilon Crucis.

Many of these brighter stars are members of the Scorpius–Centaurus Association, a large but loose group of hot blue-white stars that appear to share common origins and motion across the southern Milky Way. The constellation contains four Cepheid variables that are each visible to the naked eye under optimum conditions. Crux also contains the bright and colourful open cluster known as the Jewel Box (NGC 4755) and, to the southwest, partly includes the extensive dark nebula, known as the Coalsack Nebula.

This post is part of the Skywatch Friday meme,
and also part of the Friday Photo Journal meme.