Indian Astronomy and Astrology are so interwoven that it is difficult to say where the one ends and the other begins.

Normally, the Rahu Kala and Yama Kanda are avoided.
For any auspicious occasion it is customary to fix a Horai, time an auspicious function is to be performed.
The calculation of auspicious time depends on Day -7, Nakshatra(Star)-27), Tithi-15 (waxing and waning of the Moon), Yoga(27)and Karana(11).
These Five factors constitute the Panchanga-Five Limbs of Astrological Caculations.
Horai.
“It is common to all irrespective of their race, religion and color as our supreme guru “Surya Bhagavan” who is common to all the human beings in the world.
For selection of auspicious timings for important events like marriage, purchase of new vehicle or land and for investment purposes etc., it is important that you consult your family astrologer – as it varies for individuals based on their individual Birth star, Birth horoscope and Geo factors like latitude and longitude for the particular place.
For example
Subha Horai for a day is different for a particular day and varies from place to place. Subha Horai for Chennai will not suit for a person in Singapore or to a person in New York.
The data will be available with your family astrologers and an individual can contact for the auspicious time. However, you can always depend on the Subha Horai’s to start a new thing on a given day or to do something good or auspicious.
Horai:
There are 7 Grahas (Suriyan, Chandran, Kuja (Sevvai), Budhan, Guru, Sukra, and Sani. There are 7 Horais are named after these Grahas. Each Horai will last for one hour. These 7 Horais will occur daily on a cyclic basis, one Horai for one hour.
The order in which the Horais occur is à Suriyan, Sukra, Budh, Chandran, Sani, Guru, Kuja.
On a Sunday, for example, Suriya Horai will occur first at the sunrise. It will last for one hour. Then Sukra Horai will follow for one hour. And so on.
On a Monday, the first Horai at sunrise will be Chandra Horai (the weekday’s graham); Sani Horai, then Guru, Kuja— as per the order above, will follow it.
That is, the first Horai of the day will be the weekday’s own graham and then the order follows. On a Wednesday, the Horais will be Budh , Chandran, Sani , Guru , Kuja , Suriya, Sukran. After 7 hours this order will repeat.
Of the 7 Grahas – Chandran, Budh, Guru, Sukra are considered to be good Grahas (benevolent and auspicious); their Horais are considered good and auspicious.
Surya, Sevvai (Kuja), Sani are considered bad and inauspicious Grahas (malefic) – their Horais also are bad. Avoid these periods for any auspicious events.
Source:
http://chennaionline.com/Columns/Astrology/20131716031753/What-is-Subha-Horai.col
| Day | 06-07 | 07-08 | 08-09 | 09-10 | 10-11 | 11-12 |
|---|---|---|---|---|---|---|
| Sun | Surya (Sun) | Shukra* (Venus) | Budha* (Mercury) | Chandra* (Moon) | Shani (Saturn) | Guru* (Jupiter) |
| Mon | Chanra*(Moon) | Shani (Saturn) | Guru* (Jupiter) | Mangala (Mars) | Surya (Sun) | Shukra* (Venus) |
| Tue | Mangala (Mars) | Surya (Sun) | Shukra* (Venus) | Budha* (Mercury) | Chandra* (Moon) | Shani (Saturn) |
| Wed | Budha* (Mercury) | Chandra* (Moon) | Shani (Saturn) | Guru* (Jupiter) | Mangala (Mars) | Surya (Sun) |
| Thu | Guru* (Jupiter) | Mangala (Mars) | Surya (Sun) | Shukra* (Venus) | Budha* (Mercury) | Chandra* (Moon) |
| Fri | Shukra* (Venus) | Budha* (Mercury) | Chandra* (Moon) | Shani (Saturn) | Guru* (Jupiter) | Mangala (Mars) |
| Sat | Shani (Saturn) | Guru* (Jupiter) | Mangala (Mars) | Surya (Sun) | Shukra* (Venus) | Budha* (Mercury) |
* Longitude and Latitude of the place is to be taken into account.
The basic idea is simple. Each day is divided into hours, beginning at sunrise. If sunrise is at 7:13 AM, for example, the first hour of the day is from 7:13 – 8:13 AM. The Second hour is from 8:13 – 9:13 AM, etc. Each hour carries the energy of one of the planets. The order in which this occurs is as follows: The first planet for each day will be the ruler of the day. Sunday – Sun, Monday – Moon, Tuesday – Mars, Wednesday – Mercury, Thursday – Jupiter, Friday – Venus, Saturday – Saturn.
In calculating the planetary hours for Sunday, for example, first you look up the time of Sunrise in the newspaper. Then you designate the first hour to the Sun, the ruler of Sundays. The rest of the hours follow a set sequence – Sun, Venus, Mercury, Moon, Saturn, Jupiter, Mars.
In another example, if the day is Wednesday, then the first hour ruler is Mercury, the Second is the Moon and so on. When you reach the end of the sequence, start over with the Sun. In this way, it is simple to make a hora table for any day.(source:divine brahmananda.com)
Calculate Rahu Kala,Kuliga Kala and Yamakanda,Yoga, Karana and Tithi by clicking the Link:
http://www.astroica.com/vedic-astrology/kaal-timings.php
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http://ramanisblog.in/2011/09/18/how-to-find-and-auspicious-day-the-hindu-way/
- Ayush Homa First Birth Day Hinduism Details (ramanan50.wordpress.com)

Wanted to know when marana yogam starts on September 14th. Planning for gravrapresham between 4 to 5 am in the morning. Told it is a good day. Our stars not there on this day
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Dear sir,
I just moved to my new home for a rent on this week, can you plz suggest me auspicious dates and time to start & do the overflow of milk, thank you so much in advance.is this date is good 03.06.16 .
Manjunath
Bangalore
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