Pith Number

pith:4MCUVIBF

pith:2025:4MCUVIBFV3ZNFIR3G5PJO5Q2R4

not attested not anchored not stored refs pending

Natural experiments from Earth Hour reveal urban night sky being drastically lit up by few decorative buildings

Chun Shing Jason Pun, Chu Wing So, Constance Elaine Walker, Ho Keung Kenneith Hui, Kelly Blumenthal, Shengjie Liu, Sze Leung Cheung

arxiv:2507.02019 v1 · 2025-07-02 · astro-ph.IM · physics.ao-ph

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{4MCUVIBFV3ZNFIR3G5PJO5Q2R4}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

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.

Receipt and verification

First computed	2026-07-05T11:31:10.762730Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

e3054aa025aef2d2a23b375e97761a8f18904ffb09b666de5fec3c4126ed8b97

Aliases

arxiv: 2507.02019 · arxiv_version: 2507.02019v1 · doi: 10.48550/arxiv.2507.02019 · pith_short_12: 4MCUVIBFV3ZN · pith_short_16: 4MCUVIBFV3ZNFIR3 · pith_short_8: 4MCUVIBF

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/4MCUVIBFV3ZNFIR3G5PJO5Q2R4 \
  | 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: e3054aa025aef2d2a23b375e97761a8f18904ffb09b666de5fec3c4126ed8b97

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "17f0c1ef10e82675ff4e44e6316c85ae8997ffdca672ae0e8790c3fd77f99b92",
    "cross_cats_sorted": [
      "physics.ao-ph"
    ],
    "license": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
    "primary_cat": "astro-ph.IM",
    "submitted_at": "2025-07-02T14:27:11Z",
    "title_canon_sha256": "65707406489269444be69ee3690d1c66b20a5e55aa3e6b6b01478abac75dd6d8"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2507.02019",
    "kind": "arxiv",
    "version": 1
  }
}