Which 'Thaat' group is appropriate for 'Sandhi Prakash' category as per time theory ?

Question

Accepted Answer

The correct option is 3: Bhairav, Purvi, Marwa

The term 'Sandhi Prakash' literally means the 'juncture of light' and refers to the twilight periods—dawn (*Pratahkalin Sandhi Prakash*) and dusk (*Saayamkalin Sandhi Prakash*). According to the Hindustani classical music's Time Theory (*Samay Siddhant*), the ragas performed during these transition periods share a specific melodic characteristic: they prominently feature **Komal Rishabh (r)** and **Komal Dhaivat (d)**. The three primary *Thaats* that form the foundation for these essential twilight ragas are **Bhairav**, which governs the dawn ragas; and **Purvi** and **Marwa**, which govern the dusk/early evening ragas. Bhairav Thaat utilizes Komal Re and Komal Dha; Purvi Thaat utilizes Komal Re, Komal Dha, and Tivra Ma; and Marwa Thaat utilizes Komal Re and Tivra Ma, representing the core scales for these two key transitional times.

The incorrect options are 1, 2, and 4:
Option 1 (Bhairav, Purvi, Todi) is incorrect due to the inclusion of **Todi Thaat**. Ragas of the Todi Thaat (such as Miyan ki Todi) are generally designated for the late morning hours, specifically between 10 am and 1 pm, which is well after the true dawn *Sandhi Prakash* period (4 am to 7 am). Option 2 (Marwa, Purvi, Bhairvi) is incorrect because **Bhairvi Thaat** is often regarded as a *Sarvakaalik* (all-time) Thaat, or is conventionally sung in the late morning (around 10 am to 12 pm). While Bhairvi ragas can be played at other times, it is not a defining Thaat of the core *Sandhi Prakash* category alongside Bhairav, Purvi, and Marwa. Option 4 (Marwa, Todi, Purvi) is incorrect for the same reason as Option 1, as the inclusion of **Todi Thaat** disqualifies the group from accurately representing the three most appropriate *Sandhi Prakash* Thaats.