The 24 solar terms (节气, jieqi) divide the solar year into 24 segments of roughly 15 days each, marking each distinct shift in the sun's position and the resulting change in terrestrial energy. Classical wellness theory treats these transitions as natural inflection points — moments when the dominant qi of the environment shifts, and when our daily habits should shift with it.
How solar terms link to the six qi
The solar terms and the six qi are intimately linked. Each of the six 60-day qi steps contains exactly four solar terms, so every qi transition is anchored by a specific jieqi. The first qi step of the year begins at Dahan (大寒, "Great Cold") — not at the lunar new year — because WuYun-LiuQi follows the solar cycle. 《素问·六节脏象论》 explains this relationship, noting that the heavens' qi begins at the winter solstice and the earth's qi responds in the following weeks, with each jieqi marking a measurable step in that unfolding.
Two-week rhythm inside each 60-day step
What this means practically is that the solar terms give you a granular, two-week-by-two-week view of how the year's climate is unfolding. While the six qi provide the 60-day overview, the 24 jieqi refine that into shorter segments. A jieqi like Jingzhe (惊蛰, "Awakening of Insects") signals that wind-wood energy is rising and it is time to increase gentle movement; Bailu (白露, "White Dew") marks the arrival of autumn dryness and a shift toward resting and moisturising foods. These micro-adjustments are the daily practical layer that sits on top of the broader seasonal framework.
How TianJi surfaces the current jieqi
TianJi tracks the current solar term on its daily card and ties each jieqi to the qi step it belongs to. When you check the tool, you see not just "it is autumn" but precisely which solar term you are in, which host qi governs that term, and what the guest qi overlay adds to it. This layered view — jieqi within qi step within yearly movement — is what makes the guidance feel specific rather than generic, and every layer traces back to a cited classical source.
A wellness calendar, not a medical schedule
The solar terms are a wellness calendar, not a medical schedule. They tell you when the environment is shifting so you can adjust your lifestyle — they do not predict that a specific health event will occur. Use them as gentle reminders to realign your daily rhythm with the natural world, and consult a qualified healthcare professional for any medical concern.