The Rahu Kalam is very important in Southern Part's of India.

Rahukaalam or the period of Rahu is a certain amount of time every day that is considered inauspicious for any new venture according to Indian astrology (Vedic).
The Rahu Kalam is very important in Southern Part's of India. It Varies from Place to Place, changing every day it is based on Sunrise and Sunset at your place.
1/8th part of each day is termed as the Rahu Kalam(The period of the north node). This period will vary with different latitudes by a few minutes. The table below gives the broad time range of this period. This will be applicable to all places.
Days and Rahu Kalam Time
Monday 7:30 hrs To 9:00 hrs
Tuesday 15:00 hrs To 16:30 hrs
Wednesday 12:00 hrs To 13:30 hrs
Thursday 13:30 hrs To 15:00 hrs
Friday 10:30 hrs To 12:00 hrs
Saturday 9:00 hrs To 10:30 hrs
Sunday 16:30 hrs To 18:00 hrs

Rahukaalam - Wikipedia

https://en.wikipedia.org/wiki/Rahukaalam
Rahukaal or the period of Rahu is a certain period of time every day that is considered inauspicious for any new venture according to Indian Vedic astrology. Contents. [hide]. 1 Description; 2 Rahukaal mnemonics; 3 See also; 4 References. Description[edit]. In Hindu Vigyan, Rahu Kaal is one of the 8 segments of the day and ...

Rahukaal (also spelled as Rahukalam, Rahu kaal, Raukaal, Raahu kal, Raahu kaal, or Rahu kalam) or the period of Rahu is a certain period of time every day that is considered inauspicious for any new venture according to Indian Vedic astrology.

Contents

Description

In Hindu Vigyan, Rahu Kaal is one of the 8 segments of the day and considered inauspicious period in Indian astrology due to its association with malefic, Rahu. The segments are calculated by taking the total time between sunrise and sunset, at a given place, and then dividing this time duration by 8. Astronomically in the Hindu Panchang Panchangas, the ever varying planetary configurations mean that the auspicious hours during each day will not always fall at the same moment of time. Rahu kaal (Raahukaala), Yamagandakaala (Yama Ghantam) and Vishaghati are the time periods which are especially considered inauspicious or unlucky (Ashubh).
The planets according to Indian astronomers are the Sun, Moon, Mars, Mercury, Venus, Jupiter, Saturn, Rahu and Ketu. Rahukaal (Raahukaala) and Gulikakaal (Gulikakaala) are calculated based on these planets. Even though Rahu and Ketu are not physical bodies, they are sensitive points on the intersection of the ecliptic (the apparent path of motion of the Sun) by the Moon's orbit. Rahu is the northern point and Ketu is the southern point. Ancient astronomers felt that the mighty Rahu and Ketu have the strength to obscure the sun, thus causing a solar eclipse. Hence it is considered inauspicious to begin any undertaking during this "Rahukaal". Every day this Rahukaal lasts for around 90 minutes, but the duration differs according to the length of the time between sunrise to sunset.
It has been noticed that people use Raahukaalam as an excuse to get out of important business meetings; like in the curious case of Akshay Meetal, that happened on 11 April 2017 in Bangalore, India.
To calculate Rahukaal, the time between the sunrise and sunset is divided into 8 units or time-groups, which time-group will have the Rahukaal depends on the weekday.
For each weekday, Rahukaal falls as under:
  • Sunday - 8th Muhurt (Unit)
  • Monday - 2nd Muhurt
  • Tuesday - 7th Muhurt
  • Wednesday - 5th Muhurt
  • Thursday - 6th Muhurt
  • Friday - 4th Muhurt
  • Saturday - 3rd Muhurt

Rahukaal mnemonics

The timespan of Rahukaal varies each day and needs to be calculated as per the sunrise and sunset time. The times below can be used in absence of access to accurate Rahukaal. These times are accurate only if the daylight lasts for 12 hours, and the sunrise is at 6.00 AM. For longer or shorter days, the times need to be adjusted.
The mnemonic phrase is "7.30am Mother Saw Father Wearing The Turban Suddenly"
  • Mother = Monday (7.30-9.00)
  • Saw = Saturday (9.00-10.30)
  • Father = Friday (10.30-12.00)
  • Wearing = Wednesday (12.00-13.30)
  • The = Thursday (13.30-15.00)
  • Turban = Tuesday (15.00-16.30)
  • Suddenly = Sunday (16.30-18.00)
Another mnemonic is "Edward Bought Home A Good Ford Car".
The first letter of each word represents days of the week starting from Monday, i.e., E for Monday, B for Tuesday, and so on.
The Rahukal for Monday can be found using the following calculation:
   The letter for Monday is E.
   E is the 5th letter of the English alphabet.
   Divide 5 by 2 which is 2 and half.
   To this, add 5 (for E) which results in 7 and a half.
   Therefore, on Monday, Rahukaal starts at 7:30 and ends by 9:00.
One of the mnemonics in Tamil is "திருநாள் சந்தடியில் வெய்யிலில் புரண்டு விளையாட செல்வது ஞாயமா? "
  • திருநாள் - திங்கட்கிழமை - Monday - 0730 hrs to 0900 hrs
  • ந்தடியில் - சனிக்கிழமை - Saturday - 0900 hrs to 1030 hrs
  • வெய்யிலில் - வெள்ளிக்கிழமை - Friday - 1030 hrs to 1200 hrs
  • புரண்டு - புதன்கிழமை - Wednesday - 1200 hrs to 1330 hrs
  • விளையாட - வியாழக்கிழமை - Thursday - 1330 hrs to 1500 hrs
  • செல்வது - செவ்வாய்க்கிழமை - Tuesday - 1500 hrs to 1630 hrs
  • ஞாயமா - ஞாயிற்றுக்கிழமை - Sunday - 1630 hrs to 1800 hrs

See also