B - Planet positions
Published online by Cambridge University Press: 05 August 2012
Summary
The following table provides information on the positions of four of the five naked-eye planets and their relationships with the zodiac constellations, the Sun and each other over the years 2008 to 2017. The positions given are for the period around the start of each month.
Most of the information in the table refers to the exterior planets (Mars, Jupiter and Saturn), the orbits of which lie outside that of the Earth. The table indicates in which zodiac constellation the planet can be found around the start of each month, the months in which it is retrograding (moving to the west), and the dates on which the planet comes into opposition (directly opposite the Sun in the sky and therefore crossing the meridian at midnight) and reaches conjunction (passing behind the Sun and therefore undetectable) with the Sun.
No information is supplied regarding the planet Mercury. Mercury moves so quickly against the background of the stars that information provided once a month is of little value. Mercury is also relatively faint and hard to detect.
Somewhat similar considerations apply to Venus. Because its movement is relatively rapid, and because its brilliance makes it generally unmistakable, information is not provided regarding its position on the zodiac. However, the table shows whether Venus is a morning star (visible before sunrise in the east) or an evening star (visible after sunset in the west).
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- Information
- The Southern Sky Guide , pp. 90 - 96Publisher: Cambridge University PressPrint publication year: 2008