Mercury is the closest planet to the sun, thus it is inferior to all other planets. On the other hand, Neptune is the farthest planet to the sun and is thus considered superior to all planets. Ceres, Pluto, and other dwarf planets in the Kuiper belt are superior to Neptune. A mysterious planet-like object known as Sedna is the farthest known object orbiting our sun. Sedna is 8 billion miles from the sun and has an orbital period of 11, years, and a rotational period of There are only two planets that are inferior to Earth; Mercury and Venus.
Mercury is the closest planet to the sun and contrary to what many people believe, Earth is closer to Venus than to Mars. The closest distance between Venus and Earth is 24 million miles while the closest distance between Earth and Mars is Another assumption that people make is that the planet closest to the sun is hottest.
However, Venus is the hottest planets in our solar system and not Mercury. This is because Venus has a denser atmosphere than Mercury and therefore conserves more heat. Mars is the only rocky planet that is superior to earth; the rest are gaseous. Typically they are also visible all night long and culminate reach their highest point in the sky in darkness. Uranus and Neptune, being dimmer and more distant, less so. The latter half of will be a great time to view Mars as the planet reaches opposition on 13 October.
Find out how to make the most of it in our guide How to observe Mars. For the inferior planets, the situation is a little more complex, in the sense that they never stray too far from the Sun.
This means that they are typically stuck low down in the sky, and either rise shortly before the Sun or set not long after it. As a result, the best time to see an inferior planet is arguably when it is at greatest elongation, as this is when the period between Sun and planet rising or setting is at its greatest.
The variation stems from both planets having elliptical orbits. You should also bear in mind that the apparent diameter of any planet will change as it moves through its orbit.
For the inferior planets, this means that fuller it becomes, the smaller the apparent size of its disc. Consequently, and somewhat counterintuitively, Venus is at its brightest when it is a slender crescent because it is much closer to Earth at this time. If you think this sounds a little bit confusing, you have not been the only one.
The Ancient Greeks were convinced that the Venus that appeared in the morning and the evening were different celestial objects. They fell into the same trap with Mercury too: it bore the names Apollo and Hermes, respectively. As well as commissioning content from expert historians, he can also be found interviewing them on the award-winning HistoryExtra podcast. Credit: Roger Hutchinson.
The major orbital points of the inferior planets. Venus was a glorious evening object for the first half of Credit: Tony Titchener. The major orbital points of the superior planets.
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