Apr 3, 2009
Five of the major planets in our solar system are adequately bright enough to be visible from the night sky. These planets comprise of Venus, Mercury, Jupiter, Mars the Red Planet, along with Saturn. In spite of the fact that their luminosity alters as their locations comparative to the Earth fluctuate, however, they all, with the exclusion of Saturn, come to be clearer in our sky than the clearest star.
At the furthest point, the gradient amongst the Sun and Venus is approximately 45 degrees when Venus can rise or set longer than 3 hours ahead of, or following, the Sun. However, Mercury, which is positioned considerably nearer to the Sun than Venus, continues to be at all periods very close to the Sun in the sky and generally can be viewed with the naked eye, under good environmental conditions for only a handful of days close to each elongation.
Considering that Mercury’s trajectory is more noticeably elliptic than that of any of the additional planets which can be viewed with the naked eye, its largest extension can radiate beginning with as brief as 15 degrees to the largest of around 27 degrees. Jupiter, Saturn and mars the red planet are located further from the Sun than Planet Earth given these planets motions are slower along their trajectories than Earth. Consequently, the planets intermittently apprehends and passes, each of them. When this occurs, the planet that is being passed by the Earth, is positioned on the opposed side of Planet Earth from the Sun. This position which the planets find themselves is referred to as ‘opposition’.
When ‘opposition’ occurs, a planet is observable for the majority of the night-time, ascending close to the period of sunset and setting around the period of sunrise when it is, at its nearest to the Earth.
From then on, as planet Earth manoeuvres in advance of the planet, the planet looks to drift closer to the Sun in the sky, setting in the west increasingly earlier up to the time it is lost in the brightness of the setting Sun. Observed from the Earth, the planet next crosses behind the Sun before starting to develop on its westerly side and becoming noticeable in the easterly sky ahead of the sunrise.