Moon, Star and Science!

Science and Sages

The wealth of scientific knowledge that our ancestors possessed is simply impossible to fathom. Ironically, it takes a lot of technological advancement to understand and appreciate the scientific principles that are mentioned in our Puranas. Our ancestors were pioneers, especially in the area of Astronomy. They were able to come up with precise calculations to map the solar system (and presumably other galaxies too) and predict eclipses and other celestial events with pinpoint accuracy. The fact that they could foretell these events without any sophisticated equipment makes it really mind-boggling. In fact, some of these events span decades which indicate that not only were these great men very patient but also appreciated team work since the information was passed on from generation to generation thus advancing their research.

Chandra and Rohini

A case in point is the story of the Moon and the star Rohini. There was a time when Daksha Prajapathi, one of the eminent sons of Lord Brahma gave away his 27 daughters in marriage to Lord Chandra. Daksha also warned Chandra that he should treat all his wives the same and not show favoritism towards any of them. However, Chandra was drawn to Daksha’s fourth daughter Rohini. This caused him to spend an undue amount of time with her causing the neglect of his other wives. The other wives resented this and complained about it to their father.

Daksha got enraged and cursed Chandra thus: ‘May your powers decline with the passing of each day’. Chandra realized his mistake and then prayed to Lord Shiva. Lord Shiva appeared before him and mentioned that though Daksha’s curse cannot be entirely nullified, he would change it such that his brightness will wane for 15 days (in Krishna Paksha) and will increase for 15 days (in Shukla Paksha). The waxing and waning of the moon thus began. So goes the story.

Aldeberan and the Lunar Occultation

As we all know, our Moon takes 27 days to revolve around the earth. While doing so, the Moon is associated with a star each day, meaning 27 stars in a lunar month. The Moon circles the earth on a path called ‘the ecliptic’. During its daily journey through the ecliptic, sometimes the Moon may come in the line of a principal star. This event is called a lunar occultation. Lunar occultation is an event when the Moon passes in front of a star during the course of its orbital motion around the Earth.

The Moon’s orbit is inclined slightly with respect to the ecliptic meaning any stars with an ecliptic latitude less than about ± 6.5 degrees will be occulted by it. Though there are 27 stars present near the ecliptic of the Moon, only a few stars are within this latitude. Among all the 27 stars, Aldebaran is the brightest star that lies at 5 degrees of the ecliptic. The Moon occults with Aldebaran as much as 49 times in a span of 4 years while the occultation with others stars is not even a fraction of this number. For more details please go through the reference section given below.

Conclusion and our responsibility

Aldeberan is in fact, the star Rohini. Chandra’s affinity towards Rohini is nothing but the frequent occultation of the Moon with Aldebaran. What started as an interesting story is now a scientifically proven astronomical event! It is noteworthy that our ancestors developed the science of Astronomy (Vaanashastra /Nakshatravidya) when other civilizations were just learning to perform simple functions.

There are so many undiscovered gems such as this one in our scriptures and we will have to join hands and take them to our next generation. Another takeaway from this story is that there is a huge significance to our traditional birthdays based on the birth star. It may not be a bad idea to celebrate our kid’s birthdays in our traditional ways alongside singing ‘Happy Birthday to you’ ! 

We are also planning to come up with a series on our birthday stars soon. Please stand by.

References:

1. Soumya Santhanam for sharing this idea for a blog post
2. https://www.ted.com/talks/raj_vedam_of_ancient_star_gazers_and_story_spinners
3. https://www.universetoday.com/tag/aldebaran-occultation/