The aruNaprashna occurs as the first prashna of taittiriya AraNyaka. It is also called sUryanamaskAra prashna. This prashna contains the mantras and brAhmaNas required to perform a vedic ritual called “aruNa-ketuka cayanaM”. (Taittiriya shAkhA, being a kR^ishNa yajurveda has mantras and brAhmaNas intermixed). This ritual was supposed to have been first seen and performed by the R^ishis aruNa, ketuka and vAtarachana. Out of these, aruNa and ketuka were prominent and the ritual was named after them.
Cayana denotes the method of ritual piling vedic fire altar and aruNa-ketuka being one method. There are other methods, like nAchiketa cayana, sAvitra cayana, chAturhotrya cayana etc. The brAhmaNas describe various phalas for various chayanas.
In other cayanas, the fire altar is piled with iShTakas, that are bricks having specific dimensions and ritually baked. This cayana is different, in that, water forms the iShTaka. Water filled pots are substituted for bricks. The water should be appropriately filtered with dashApavitra cloth.
The protocol briefly is as follows:- A pit like ratha chakra (chariot wheel) is dug on a clean place. The depth of the pit should be equal to the length of yajamana’s foot to the knee. In this pit, water is filled for the length of yajamana’s foot to the ankle. On top of it, lotus leaves are placed. Then lotus stems are placed, follwed by entire lotus plant having its roots intact.
On this, a wooden pITha is installed and agni is placed on the pITha. Beneath the pITha, water filled pots are piled using the mantras given in this prashna. Once the piling is complete, yaGYas like pashubandha or as per the saMkalpa is performed.
The water for the east side of the altar should be collected from the rain when there is sunshine too. This water denotes brahmavarchas. The water for the south side should be collected from well. This water denotes tejas. The water for west side should be collected from water bodies like a tank, where the water is static. This water denotes firmness. The water for the north side should be collected from flowing river. This water denotes bala (or strength). The water for the center should be from earthern pots stored in house. This denotes “establishment on earth”. Finally, water is collected from a water body which does not dry up at all and this is placed on top of the center water pots. By this the yajamana attains “establishment on heavens”.
The ritual also contains protocols to place a tortoise and gold in the altar.
There are vratas to be kept while learning this prashna and while before performing the ritual. This has to be learnt from a guru in araNya (forest). That is why it is called AraNyaka. Before beginning, one has to utter the shAnti mantras starting with “bhadraM karNebhiH”. With mahAnAmnIs and “ApamApamapaH sarvAH”, one should touch water. With “shivAnaH”, one should touch herbs (oShadhI). With “sumR^idIkA sarasvatI”, one should touch the floor. One keeps the vrata till the end of adhyayana. At the end, one has to donate cow, copper vessels, silk cloths or other things within his means to the AchArya.
Before performing the ritual, one has to observe vratas for 1 year or 2 months (yathA shakti). One has to bathe thrice a day. One has to eat only alternate nights. If he can’t do this, he may eat food obtained by begging. One should not do Achamana and praxAlana directly from a water body. One should not store food for the next day. One has to offer oblations to agni, vAyu, soma, brahmA, prajApati, chandramas, naxatras, sUrya, seasons, year, varuNa and aruNa daily. One has to perform homa to kANDa R^ishis called AruNas.
Some salient features of the mantras in this prashna–
1. Contains beautiful description of seasons, as the sun moves to complete one year cycle.
2. Refers to 7 suns like bhrAja, paTaram pata~Nga etc. deriving their power from the 8th sun kashyapa who is firm. Also, alludes to thousands of solar systems.
3. Refers to shataghnI, an interesting weapon described in dhanurveda and was used as a ballista. It was supposed to be packed with lohakaNTa (iron spikes), suggesting that it was an incendiary device that fired on being hurled and also spewed iron spikes.
4. Contains the R^igvedic mantra “amIya R^iksha nihitA sa ucchA…”. R^iksha refers to the saptraR^ishi mandala – Ursa Major. This mantra contains an important astronomical clue to date the R^ig veda.
5. Contains the ancient story of prajApati meeting kUrma, which forms the kernel for later purANic story of kUrmAvatAra.