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Astronomy: Infinite Cosmos

Purnamadah purnamidam | Purnat purnamudachyate
Purnasya purnamadaya | Purnamevavashishyate.
[infinite Brahman - Isha Upanishad]
"That [Brahman, the Supreme Being] is infinite (full, complete). This [physical Universe] is infinite. From the infinite [Brahman], the infinite [Universe] came into being. The infinite [Brahman] having the infinite [Universe] taken away, remains infinite."

Astronomy Myths

Vedic Astronomical Values

The Sanskrit word "jyotish" referred to the study of astronomy and astrology both; as in other cultures of the day, astronomy and astrology were considered inseperable. The astronomical methods outlined in the Vedanga-jyotisha were thus in use in India for a long time. It is clear in the text of Surya Siddhanta and the current practice of Indian astrology that sidereal measurements are of primary importance. Tropical measurements are also used but in a secondary way.

Saptarishi Mandala

Mandala means Circle, Saptarishi means 7 sages. The 7 stars of what we call is the Great Bear (Ursa Major) or Big Dipper, have been named after The Seven Sages or the Sapta Rishis in Indian Astronomy. Sapta Rsha (Seven Sages), might have been distorted old Germanic word Sapta Rksha (Seven Bears).

The seven sages are Marici to the east (alpha), Vasishta (beta) to his west, then Angiras (gamma), then Atri (delta), then Pulastya (epsilon), then Pulaha (zeta), and Kratu (eta)” (5 and 6) : Brihat Samhita of Varahamihira. There are two sets of definitions as to who the saptha Rishi's are.

The vedic tradition is 'Gautama, Vishwamithra, Jamahagni, Bharadwaaja, Kashyapa, Vasishtha and Athri' are the saptha rishis. However, the saptha Muni's according to Varahamihira are' Marichi, Vasishtha, Angirasa, Athri, Pulasthya, Pulaaha, and Kruthu'.

Dhruva is Polaris. 'Marichi' stands for Alkaid, 'Vasishta' stands for Mizar, 'Angirasa' stands for Alioth, 'Athri' stands for Megrez, 'Pulasthya' stands for Phecda, 'Pulaaha' stands for' Merak and 'Krathu' stands for DuBhe. The companion star for Mizar is Alcor. Hence 'Arundhathi' stands for Alcor. Vasishta and Arudhathi (Mizar-Alcor) can not be seen separate. The star Arundhathi is difficult to separate from Vasishta for people with poor eyesight.

Planets - Grahas

The ancient astronomy was geocentric and so Earth was not taken as a graha. In addition to the Sun and the Moon, the ancient peoples could find, by naked eyes' observations, only the following five planets: Mars, Mercury, Jupiter, Venus, and Saturn. These seven heavenly shining bodies were found to have angular motions relative to fixed stars. They constituted the early list of seven planets leading to the present concept of a 7-day week. Ancient peoples believed that the positions and configurations of planets have great influence on the life of individuals and on the course of events in the world and nature. Since remote times, man has been worshiping objects of nature and was involved in their personification.

In ancient India, all the nine planets (navagrahas) were personified as male deities. Graha is the one which moves in the sky. Around the time of Gautama Buddha, 9 graha system became popular, by including Rahu and Ketu. Rahu and Ketu denote the two points of intersection of the paths of the Sun and the Moon as they move around the celestial sphere.


Rahu and Ketu denote the two points of intersection of the paths of the Sun and the Moon. The fact that eclipses occur when Sun and Moon are at one of these points gives rise to the myth of swallowing of the Sun or moon. The fact that eclipses occur when Sun and Moon are at one of these points gives rise to the myth of swallowing of the Sun or moon.

The historical record of eclipse cycles known as the saros is by Chaldeans. Three periodicities related to lunar orbit, the synodic month, the draconic month, and the anomalistic month coincide almost perfectly each saros cycle. The Saros is a period of approximately 18 years, 11 days, 8 hours), that can be used to predict eclipses of the Sun and Moon. The eclipse season (34 days long on average) is longer than the synodic month. Rahu and Ketu passes through all the 27 Nakshatras in 18 years during its transit. It stays in one Nakshatra for about 8 months or 4 seasons (ruthu). So total 108 seasons.

Vedanga Jyotisa, supposedly composed by Rishi Lagadha makes no mention of the eclipse calculations.Rahu is nowhere mentioned in the Rig, Sama and Yajurveda. In the Atharvaveda, the description of Ketu is more suited for what we today call a comet (Dhumketu). Only in the Navagrahastotrom, Rahu and Ketu starts getting importance. 9 was the magic number. To make it 9, these two would have been added to 7 visible grahas. 28 star (7*4) of chaldeans became 27 star (9*3) of puranic astrology. Abhijit was removed from zodiac. This was also used to link it to comets in stories. Eventually added as story in Bhagvata Purana, during Golden age of Guptas.

The Surya Siddhanta gives detailed methods for making ecliptic calculations. Rahu and Ketu were astronomically defined to be the ascending and the descending nodes of the lunar orbit, intersecting the plane of the Earth's orbit.

Humans have watched eclipses since creation. Many of the popular (religious) ideas about the causes and effects of eclipses is views of small group of people (astrologers and story tellers). A lunar eclipse — an eclipse of the Moon — is perfectly safe to watch with the naked eye; you're only looking at the Moon, at night, which is quite safe. A solar eclipse is potentially dangerous, however, because viewing a solar eclipse involves looking at the Sun, which can damage your eyesight. May be good to protect eyes, if you look at Sun (any time). Total solar eclipses are terrifying and their ghostly green coronae look frightening. But is is just a natural cycle like day and night.

During a total solar eclipse when the disk of the moon fully covers the sun, the brilliant corona emits only electromagnetic radiation, though sometimes with a greenish hue. Deep in the solar interior where nuclear fusion takes place to light the sun, particles called neutrinos are born, and zip unimpeded out of the sun and into space. Every second, your body is pelted by trillions of these neutrinos no matter if the sun is above or below the horizon. The only consequence is that every few minutes a few atoms in your body are transmuted into a different isotope by absorbing a neutrino. There is no evidence that supports the idea that lunar eclipses have a physical effect on people. But it does admit that eclipses can produce “profound psychological effects” that can lead to physical effects because of the beliefs people have and the actions they take because of those beliefs. [NASA]

There will be some effect of eclipse on sea tides, climate. Science finds no physical links to eclipses and the beliefs about eclipses. Eclipses, often viewed as signs or evil omens have led ancient tribes to sacrifice animals and other humans to sway what is seen as the angry mood of the gods. Eclipses are harbingers of something very bad about to happen. Eclipses foretell major life changes and events about to happen. Every one's life follows some pattern and there is some sort of rhytm. Nature also has its own cycles and pattern. There can be some correlation between them. WE really do not know, how much. This is based on one's personal experience. We tend to remember all the occasions when two things happened together, but forget all of the other times when they did not.

In Hindu astrology, the eclipses are considered inauspicious. People in Tantric practices consider full moon day, new moon day and solar and lunar eclipse as powerful for paranormal activities. It is believed that the evil forces are appeased on these occasions.

Customs to be observed are given in many textbooks. The inauspicious period begins half a day before a solar eclipse and 3/8th day before a lunar eclipse. The water, clothes, food grains, etc., are sprinkled with the tarba or tulasi leaves. After a bath perform rituals like tarpana, sraddha, homa, prarthana and give donations. After the eclipse is over, one more bath, to erase the unholy shadow of Rahu. Some go to some sacred place or to the nearest seashore for taking a holy bath. There is a strong belief that any donation given during the eclipse hours is most auspicious. Now, MANY do not follow these TO THE DETAIL.

One can say some simple prayer or do some rituals. If you want to be on safe side, you can avoid eating couple of hours before eclipse. Pregnant women need not watch an eclipse. Do not keep food open.

Special numbers

Indian astronomers

Ancient astronomers are also called as rishis. Agasthya Rishi crossed vindhya mountains southwards and it is a major event in the vedic chrononlogy. A star in southern extreme is named after Agasthya or Canopus in constellation Carina.
There were many astronomers and many works have been lost. Few are discussed below:
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