Pith Number

pith:VAS3NYIR

pith:2026:VAS3NYIRLQAMP7K53RN3DBCSBK

not attested not anchored not stored refs pending

Lunar nutation effect defines the sign of the Earth rotation rate for now, but this may change soon

Oleg Titov

The 18.6-year lunar nutation cycle now fully dictates Earth's length-of-day changes, overriding the long-term secular slowdown.

arxiv:2604.11126 v2 · 2026-04-13 · astro-ph.EP

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\usepackage{pith}
\pithnumber{VAS3NYIRLQAMP7K53RN3DBCSBK}

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Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Claims

C1strongest claim

At the moment the LOD changes are completely determined by a signal with a period of 18.6 years. More detailed extrapolation reveals that LOD is likely to vary in a range between -1 ms to +1 ms until 2050 or may be longer.

C2weakest assumption

That the 18.6-year lunar nutation signal and other harmonics can be cleanly separated from the secular trend in the LOD time series without significant cross-talk, data selection effects, or unmodeled noise that would alter the conclusion of complete current dominance.

C3one line summary

Current LOD variations are completely determined by the 18.6-year lunar nutation signal, with day length expected to stay within -1 ms to +1 ms of average until 2050 or longer.

Receipt and verification

First computed	2026-06-23T03:13:57.125313Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

a825b6e1115c00c7fd5ddc5bb184520a9761eb79840ff2718cd0b44ee4c6b890

Aliases

arxiv: 2604.11126 · arxiv_version: 2604.11126v2 · doi: 10.48550/arxiv.2604.11126 · pith_short_12: VAS3NYIRLQAM · pith_short_16: VAS3NYIRLQAMP7K5 · pith_short_8: VAS3NYIR

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/VAS3NYIRLQAMP7K53RN3DBCSBK \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: a825b6e1115c00c7fd5ddc5bb184520a9761eb79840ff2718cd0b44ee4c6b890

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "3dd4662c3dc911d291e6a025a068c97a49211ec82bf79d906cd4bb64e6216cb3",
    "cross_cats_sorted": [],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "astro-ph.EP",
    "submitted_at": "2026-04-13T07:41:58Z",
    "title_canon_sha256": "84ef8e4081b710bbf51f00b0abe515bedfaec8329661483d0c7955eb3080ab3b"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2604.11126",
    "kind": "arxiv",
    "version": 2
  }
}