Uttarayana as the name indicates it means ascent of the sun towards Uttara (North) direction. It is also called Aadana Kala as there is a reduction of strength in human beings and nature. As of modern science, it is called as Northern solstice.
DEFINITION
उत्तरां दिशां प्रति अयणं गमनम् इति उत्तरायणं ।।
(अ. हृ. ३/२ टीका)
The movement of the sun in northern direction is uttarayana.
आददाति क्षपयति पृथिव्याः सौम्यांशं प्राणिनां बलमित्यादानम् ।।
The ayana reduces the saumya or mild qualities from the earth and takes away the strength of human beings.
शिशिराद्यैस्त्रिभिस्तैस्तु विद्यादयनमुत्तरं ।
आदानं च तदादते नृनां प्रतिदिनं बलं ।।
(अ.हृ. ३/२ )
Sishira, Vasanta & Grishma Ritu together form Uttarayana which brings about a reduction of strength.
CAUSE FOR DECREASE OF STRENGTH DURING ADANA KALA
तस्मिन् ह्रुत्यर्थ तीक्ष्णोष्ण रूपा मार्गस्वभवतः।
आदित्य पवनाः सौम्यान् क्षपयन्ति गुणान् भुवः ।।
तिक्त कषाय कटुको बलिनोत्र रसाः क्रमात् तस्मादादानं आग्नेयं ।।
(अ. हृ. ३/३)
The intensity of sun is more and wind is dry, which reduce the mild properties of the earth. Tikta, Kashaya and Katu rasas respectively are predominant in this season.
EFFECT OF ADANAKALA ON THE BODY
तत्र रविर्भाभिराददानो जगतः स्नेहं वायवस्तिव्र रुक्षाश्चोपशोषयन्तः शिशिर वसन्त ग्रिष्मेषु यथा क्रमं रौक्ष्यमुत्पाद्यन्तो रुक्षान् रसांस्तिक्त कषायकटूकान्श्चाभिवर्धन्ते नृणां दौर्बल्यमावहन्ति ।।
(च. सू. ६/६)
During the period of Adanakala, not only sun rays but the wind have sharp velocity and dryness absorb the moisture from the earth, the three seasons have increased Tikta, Kashaya and Katu rasa respectively, which brings about dryness in the body and reduce the bala.
आददान उच्छोषयन् ।।
(आ. र )
Fast, dry winds and intense heat of sun dries the body.
RELATION BETWEEN SEASON, STRENGTH AND PREDOMINANT TASTES
| Rutu | Raukshya | Rasa | Panchabhuta | Bala Hrasa |
|---|---|---|---|---|
| Shishira | Alpa | Tikta | Akasha | Alpa |
| Vasanta | Madhya | Kashaya | Pruthvi, Vayu | Madhya |
| Grishma | Pravara | Katu | Agni, Vayu | Maha |
If we analyze the dryness in environment and rasa. Kashaya rasa is more dry compared to katu rasa. Grishma rutu is more dry than vasanta rutu. Considering the predominance of taste, vasanta rutu is predominant in kashaya rasa and grishma rutu is predominant in katu rasa. Here we infer that Vasanta is kapha prakopa kala, so dryness brought about by kashaya rasa is pacified by kapha, thus making it madhya ruksha.