A few hours ago, both söma and āditya were in jyēşțha nakşatra, third pāda.
And we had an amāvāsya in vŕscika rāśi.
This means that we had a new moon because the sun and moon had the same degree longitude. Scorpio was in the background.
The sun and moon and other grahas step through the 12 rāśis, in 108 steps or pādās. 360 degrees/108 pādās gives us 3.3 degrees per pāda.
The sun completes 360 degrees in 365.25 days, which is about 1 degree a day or about 1 pāda in 3 days.
The moon traverses 108 pādās in about 27 days.
This is about 4 pādās or one nakşatram a day.
By the time söma takes 12 steps, ravi takes one step. By the time candra has completed all 27 nakşatrams, sūrya has taken 9 steps.
This means, that mitra has moved one rāśi in the time that söma has completed all 12 rāśis. So the next new moon cannot be in jyēşțha nakşatram 3rd pāda. It actually works out as the fourth pāda of pūrvāşāđa.
Thus we see that amāvāsyās and pūrņimās occur in different nakşatrās each māsa.
When the caitra pūrņima occured in anurādha nakşatra, hanumān was born.