True Flaptime
Flaptime counts the beat of a real pulsar. True Flaptime lays that count over the sky: the sun rising and setting where you stand. The day isn't cut into equal pieces. It is counted in pulses, and split where the sun splits it.
Time something
A countdown in pulses. Pick a block, or type a count. It chimes at the end.
Mark a moment
Tie it to the sky. A mark that repeats every turn keeps its place in the day as the seasons move.
Meet someone
A pulse is the same instant for everyone, everywhere. Pick one, send it, and each of you sees it in your own sky. Round spans are easy to say: span 3,530 starts at pulse 3,530,000.
The tides drift
Light per turn, for the turn before this one and the turns ahead. The bar is one whole turn; the gold part is its light. Nothing here is fixed: the share of light moves every turn with the seasons.
Words of True Flaptime
- Pulse
- One beat of PSR B1919+21: 1.337302088 seconds. The only fixed unit. Pulse 0 is the moment Flaptown Advancements LLC was confirmed.
- Turn
- Sunrise to the next sunrise. Its length in pulses changes a little every turn. Turns are numbered by counting sunrises since pulse 0.
- Light and Dark
- The two tides of a turn: sunrise to sunset, sunset to sunrise. Their lengths are measured, not decreed.
- Crest and deep
- The pulse when the sun stands highest, and when it lies lowest. They split each tide into a rising and a falling part of whatever size the sky gives.
- Height
- How high the sun stands, as a share of today's crest (in Light), or how low, as a share of tonight's deep (in Dark).
Human rhythm
The pulse count breaks into units that match how people actually work, rest and sleep. Real durations are shown only to compare with the research.
| Unit | Pulses | Matches | Why |
|---|---|---|---|
| beat | 1 | 1.34 s | About a resting heartbeat. Two beats span the "psychological present", the 2–3 s window people experience as now (Pöppel). |
| pause | 100 | 2.2 min | A microbreak. Short breaks of a few minutes restore vigor and reduce fatigue (Albulescu et al., 2022 meta-analysis). |
| span | 1,000 | 22.3 min | One block of sustained attention: vigilance falls off after 20–30 min (Mackworth's vigilance research). Also the length of a restorative nap without grogginess (Brooks & Lack, 2006). |
| cycle | 4,000 | 89.2 min | The basic rest–activity cycle (Kleitman): one sleep cycle at night, and the rise and dip of alertness by day. Three spans of focus, one span of rest. |
| sleep | 20,000 | 7.4 h | Five whole cycles, inside the 7–9 h adults need (AASM), ending at a cycle boundary so waking is easy. |
| turn | ≈ 64,600 | sunrise to sunrise | About sixteen cycles. Anchoring the day to the sun instead of a clock grid is the remedy chronobiology proposes for social jetlag (Roenneberg). |
Read a count as spans: in 18,402 the thousands are the spans (18) and every fourth span closes a cycle. Shared moments fall on the sky's own marks: rise, crest, set.
The formula
P(t) = ⌊ (t − t₀) / 1.337302088 s ⌋ the pulse at moment t; t₀ = pulse 0 h(P) = the sun's altitude at pulse P, from its position over (φ, λ) rise = a pulse where h crosses −0.833° going up (the sun's upper edge meets the horizon, set = a pulse where h crosses −0.833° going down refraction included) turn T = [ riseₙ , riseₙ₊₁ ) length T = riseₙ₊₁ − riseₙ (pulses) Light L = [ riseₙ , setₙ ) length |L| = setₙ − riseₙ Dark D = [ setₙ , riseₙ₊₁ ) length |D| = riseₙ₊₁ − setₙ crest = argmax h over L deep = argmin h over D reading(P) = ( tide, P − tide start, tide end − P, (P − tide start) / |tide|, h(P) / h(crest) or h(P) / h(deep) ) turn number = how many sunrises lie between pulse 0 and P
The crossings are found by stepping through the pulses and narrowing in until the exact pulse is found. Rhythm units: span = 1,000 pulses, cycle = 4,000, sleep = 5 cycles ending at the next rise. Degrees appear only inside the astronomy that places the sun; the clock itself speaks in pulses and shares.
Keep True Flaptime
This page measures your own sky: choose "Use my location" below and your device tells it where you are. Your location stays on your device. To keep the clock, download it as one file and open it in any browser, even offline.
Where the sun is measured
Kansas City, Missouri, Flaptown's home. Your place is remembered in this browser only.