# Kālakriyāpāda — the synodic and the sidereal month distinguished
model.geocentric
reset
show.bodies
show.moon
show.phases
show.constellations
show.eclipticBelt
now
overlay.show There are two ways to say the Moon has gone round once, and they give different answers
overlay.show Back to the same star, or back to the same phase — watch both markers
wait.next Run three months

overlay.clear
speed.set 8
repeat 3
  play.until.new-moon
  overlay.clear
  overlay.show New moon (synodic) {date} · {moon.nakshatra}
  wait 1
  play.until.sidereal-return
  overlay.clear
  overlay.show Sidereal return (~27.3 d) — Moon back to the same star
  wait 1
end
pause
overlay.clear
overlay.show The sidereal month always arrived first, about two days ahead of the new moon
wait.next Why the gap?

overlay.clear
overlay.show Because the Sun moved too. While the Moon went round, the Sun advanced about 27° along the ecliptic
overlay.show The Moon has to chase that extra arc to line up again — those are the missing two days
overlay.show 27.32 days sidereal, 29.53 synodic. The calendar counts the second; the nakshatras count the first
wait.next Done

overlay.clear