# C1237 — Derive the three Moses cycle spans from the full path

## Question

How do the430 and490 families share this source chronology?

## Inputs

```json
{}
```

## Sources

```json
[
  "C1236",
  "File51a §7A.1"
]
```

## Opened utc

2026-09-28T05:40:43.642062+00:00

## Results

```json
{
  "cycle_family": {
    "path": "model/Moses_cycle_family.json",
    "sha256": "383622af80e02a860a556b78cab0e461136ba9ff53e4266e2f32899288d61ab4",
    "bytes": 479
  },
  "spans": [
    2580,
    2450,
    1960
  ]
}
```

## Finding

The complete path yields2580=6×430,2450=5×490 and1960=4×490. Their shared chronology and initial130/490 blocks explain the correspondence as one family.

## Reassessment

Test exactly what the130 bridge does and does not determine.

## Checks

```json
{
  "cycles": true,
  "ordered_subtractions": true
}
```

## Closed utc

2026-09-28T05:40:43.642740+00:00

## Record provenance

Exact record hash: `1fd6b282ac7dd6df3e1b48b42b04e4d1d9e505c9e4a5d87046bb01a7a0dfb7aa`

Source journal: `Research_Cycles/C1132_C1431_Recovered/journal.json`