This simple astronomical observation would help you to find if Jupiter is retrograde in a horoscope?
Retrogression is a fascinating concept in astrology. It is astonishing that Indian astrological text included the concept of retrogression and its influence several centuries ago without any modern scientific devices. Retrograde is an important phenomenon that confirms that ancient Indian seers had understanding about Heliocentric solar system. For more details about this, you can refer this article. For the present topic of interest I am discussing how to find retrograde planets in a horoscope with a simple technique.
Why Retrogression happens?
For the farther planets like Jupiter, Saturn the retrogression occurs during the planets at Aphelion(farther distance from Sun), due to the fact that at aphelion the planet will move slower and hence when viewed from earth it will appear to move backward. For example, when Jupiter is at aphelion it will move in slow motion, at the time when we view Jupiter from earth the Jupiter will look like moving backward. You can imagine retrograde motion to an overtaking car while overtaking with respect to the speeding car the slower car appears to move backward.
How to find retrogression easily without any software?
For Jupiter, the peak retrogression occurs when farther away from the Sun. The Jupiter will be in peak retrogression when occupies 7th house from the Sun. The actual retrogression last for ~120 days. So ideally the retrogression would start when Jupiter come midpoint of the 5th house from Sun and retrogression end when Jupiter crosses midpoint of the 9th house. The earth takes 365 days to complete one revolution around the Sun, so the Sun will appear in one Zodiac for roughly ~30 days. Since the retrogression of Jupiter lasts for ~120 days, two sign back from the 7th house and 2 signs forward from 7th house of Sun will indicate that Jupiter is in retrogression.
So next time when you look at your natal chart, if Jupiter occupies 6th or 7th or 8th house then you can certainly say that Jupiter is retrograde. If Jupiter occupies the 5th house or 9th house then Jupiter may be retrograde or not based on the degree it occupies. I hope you find this technique very easy to use. Please feel free post your view in the comment section.