Science in Hindu Vrats & Upvas

This is claimed that Snatana Dharma is purely scientific. Truly, the Snatana Dharma is developed after research of thousands of years by rishis (ancient Hindu scientists, seers). This website www.dnaofhinduism.com attempts to highlight the scientific basis of Snatana Dharma.
 
As per modern Astronomy, sun passes through the constellations that formed the Zodiac: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces. Under the influence of gravitational force and because of the orbital path combination of sun, moon and earth, lunar and planetary bodies impact on human bodies. Lunar cycle has eight phases are, in order, no or new Moon (completely dark side facing earth), waxing crescent (tiny portion visible), first quarter (half-moon visible), waxing gibbous (most of the moon visible), full Moon, waning gibbous (illuminated side shrinking), third quarter (half illuminated) and waning crescent (thin curve). The cycle repeats once a month (every 29.5 days).
 
Scientific Significance:
The modern science has researched as follows:

1. The sun, earth, and moon interact in a complex ballet of motions and forces. All bodies with mass in the universe attract each other. The earth's pull on the moon keeps the moon in orbit, and the sun's pull on the earth keeps the earth in orbit.
2. Based on the exact positions of the three bodies, phases and eclipses; sea tides, the seasons etc. occur.
3. The gravitational pull of the Moon is known to influence ocean tides - and as the human body is composed of about 60% water, it stands to reason that the influence may extend to affect us in some way as well.
4. The lunar cycle has an impact on human reproduction, in particular fertility, menstruation, and birth rate. Melatonin levels appear to correlate with the menstrual cycle. Admittance to hospitals and emergency units because of various causes (cardiovascular and acute coronary events, variceal haemorrhage, diarrhoea, urinary retention) correlated with moon phases. In addition, other events associated with human behaviour, such as traffic accidents, crimes, and suicides, appeared to be influenced by the lunar cycle.
5. Animal studies revealed that the lunar cycle may affect hormonal changes early in phylogenesis (insects). In fish the lunar clock influences reproduction and involves the hypothalamus-pituitary-gonadal axis. In birds, the daily variations in melatonin and corticosterone disappear during full-moon days. The lunar cycle also exerts effects on laboratory rats with regard to taste sensitivity and the ultrastructure of pineal gland cells.

Spiritual Significance:
The dates viz. Sankranti, Chaturthi, Ekadashi, Trayodashi, Purnima and Amavasya, are important in Hinduism. Most of the festivals are celebrated on these dates and vrats and upvas are observed. The question is “Why so.” These dates in Hindu calendar coincide with astronomical facts which has correlation of Sun, Moon, Earth and Stars. Sankranti, Chaturthi, Ekadashi and Trayodashi are the astronomical dates specially dedicated to five deities – Sankranti – Sun, Chaturthi – Sri Ganesh, Ekadashi – Sri Vishnu and Trayodashi – Shiv ji and Ma Parvati.
 
Chaturthi (4th date) dedicated to Sri Ganesh:
Fourth day falling after full moon (Purnima) in Krishna Paksha is called as ‘Sankashti Chaturthi’ and fourth day after new moon (Amavasya) in Shukla paksha is termed as ‘Vinayaka Chaturthi’. The word “Sankashti” comes from Sanskrit and implies “freedom from difficult times”.
 
In Hindu scriptures, Chaturthi Tithi belongs to Lord Ganesh, son of Lord Shiva and Goddess Parvati. Lord Ganesh signifies prosperity, wisdom and good fortune. He is believed to be the remover of obstacles and also the lord of learning. On Sankashi Chaturthi, devotees worship Lord Ganesh to overcome their hurdles in life and to come out as an achiever in difficult times.

Ekadashi (11th date) dedicated to Sri Vishnu:
Devotees of Bhagwan Vishnu observe Ekadashi fasting to seek His blessings. It falls on 11th day of lunar month. There are two Ekadashi fasting in a month, one during Shukla Paksha and another during Krishna Paksha. 24 Ekadashi occur during the year (January – Pausha Putrada Ekadashi, Saphala; February – Jaya, Shattila; March – Amalaki, Vijaya; April – Kamada, Papmochani; May – Mohini, Vaishnava Varuthini; June – Nirjala, Apara; July – Devshayani, Yogini; August – Shravan Putrada, Vaishnava Kamika; September – Parsva, Aja; October – Papankusha, Indira; November – Devutthana, Rama; December – Mokshada, Utpanna.    
 
According to Hindu scriptures, Ekadashi and movement of the moon has a direct correlation with the human mind. It is believed that during Ekadashi, our mind attains maximum efficiency giving the brain a better capacity to concentrate.
 
Study says, from the eleventh day till fifth day post new moon or full moon day, moon influences us maximum and imbalance our digestive system. This also cause decrease in brain's functioning and cause weakness in memory, thought and decision making. Therefore, to avoid all these complications, it's important to clean our digestive system on every 11th day of lunar cycle. This helps our digestive system to clean up all the food and mess in our body. That is why fasting is done on Ekadashi.
 
Pradosh (13th date) dedicated to Shiv ji and Ma Parvati:
Pradosh Vrat or Pradosham is a popular Hindu Vrat that is dedicated to Bhagwan Shiva and his wife, Goddess Parvati. Devotees observe this vrat for eternal bliss, spiritual upliftment and good health. It falls on trayodashi or 13th day of lunar month. There are two trayodashi fasting in a month, one during Shukla Paksha and another during Krishna Paksha. 24 Pradosham occur during the year.
 
Purnima (Full Moon):
Purnima or the full moon is widely recognized as a symbol of fullness, abundance, and prosperity in Hindu belief. Several Hindu festivals in Panchang are aligned with the full-moon day, which is considered a benign and blessed occurrence. There is 12 Purnima in a lunar calendar. January – Pausha Purnima; February - Magha; March - Phalguna; April - Chaitra; May - Vaisakha; June - Jyeshta; July - Aashaadha; August - Shraavana; September - Bhadrapada; October - Ashwin; November - Kartika; December – Margashirsha.
 
Several festivals fall on Purnima such as Guru Ravidas Jayanti on Magha Purnima; Chhoti Holi on Phalguna Purnima; Hanuman Jyanti on Chaitra Purnima; Buddha Purnima on Vaisakha Purnima; Vat Purnima on Jyeshta; Guru Purnima on Aashaadha Purnima; Raksha Bandhan on Shraavana Purnima; Pitrpaksha begins on Bhadrapada Purnima; Sharad Purnima on Ashwin Purnima; Dattatray Jayanti on Margashirsha Purnima.
 
Shri Satyanarayan Puja is also performed on every Purnima to seek the blessings of Lord Narayan. Narayan is an incarnation of Lord Vishnu.

Amavasya (No or New Moon):
Amavasya is the one when no moon is visible in the sky. Amavasya occurs once a month, with 12 such no moon days falling in a year. Being the darkest day of the month, Amavaysa is considered one of the most powerful and impactful times of the year.
 
Several important rituals and traditions are observed on this day by devotees across India. February (Magh) – Mauni Amavasya; May (Jyeshta) – Shani Jayanti, Vat Savitri Vrat; August (Bhadrapada) – Pithori Amavasya; September (Ashwin) – Sarvapitri Amavasya; October (Kartika) – Diwali, Laxmi Puja, Sharda Puja, Bengal Kali Puja.
 
Sankranti dedicated to Sun:
Sun stands for “Pratyaksha-Braham”, “a manifestation of the Absolute”, bestowing knowledge, spiritual light, and wisdom.
 
Sankranti are the days of transmigration of sun from one zodiac to another. January – Sun enters in Makar Rashi (Capricorn); February – Sun enters in Kumbh Rashi; March - Sun enters in Meena Rashi; April - Sun enters in Mesha Rashi; May - Sun enters in Vrishabha Rashi; June - Sun enters in Mithuna Rashi; July - Sun enters in Karka Rashi; August - Sun enters in Simha Rashi; September - Sun enters in Kanya Rashi; October - Sun enters in Tula Rashi; November - Sun enters in Vrishika Rashi; December - Sun enters in Dhanu Rashi.
 
Makar Sankranti is a special festival across the country, where the God of Sun is worshipped and gratitude is shown by offerings and prayers. The festival of Makar Sankranti is celebrated in every state with different names. But the essence remains the same. In Andhra Pradesh, Sankranti is known as Pedda Panduga, Makar Sankranti in North & Karnataka, Magh Bihu in Assam, Magha Mela in the regions of central and north India, Uttarayan in Gujarat, Khichdi Sankranti in Uttar Pradesh, Pongal in Tamil Nadu. A day prior to Makar Sankranti is Lohri, a harvest festival of Punjabi.
 
Most of the Hindu festivals are celebrated as per the lunar cycle of the Hindu calendar. But Makar Sankranti is celebrated as per the solar cycle. It falls on Georgian date every year (January 14) except in some years when date might shift to a day of that year. It is due to the revolution of the Earth around the Sun. It marks the commencement of sun’s journey to northern hemisphere (Uttarayana). On this day, taking bath in the rivers purify the self.