OSINTDatasetNewAdded 2026-11-13

SILSO sunspot number data (WDC-SILSO)

International sunspot number, daily to yearly, as keyless CSV and text files

FreeNon-commercial onlyauth: noneCC-BY-NC-4.0✓ verified Nov 13, 2026

Free?: FreeNon-commercial use only. Free keyless CSV and text files.
Sign-up?: None neededCall it straight away
Commercial use?: Not allowedCC-BY-NC-4.0: non-commercial only

Non-commercial use only: WDC-SILSO publishes the sunspot data under CC BY-NC

The WDC-SILSO data files page says:

“The World Data Center SILSO has adopted an open data policy”

“Data policy: CC BY-NC”

Source: WDC-SILSO: Data files (checked Nov 13, 2026). This isn't legal advice.

For other space-weather data in the catalog without a non-commercial restriction in their terms, see:

Each source has its own terms; read its licence note before you use it.

The fine print

License note: Non-commercial use only. The data page says "The World Data Center SILSO has adopted an open data policy" and "Data policy: CC BY-NC", linking the CC BY-NC 4.0 deed. Credit WDC-SILSO. Signal Lab links only.
Required attribution: Required by CC BY-NC 4.0: credit WDC-SILSO, Royal Observatory of Belgium.

Open sidc.be

The prompt works in any assistant connected to Signal Lab.

The short version. Switch to see exactly what an AI agent reads.

// Overview

SILSO sunspot number data (WDC-SILSO)

WDC-SILSO at the Royal Observatory of Belgium publishes the international sunspot number series: daily, monthly, smoothed and yearly totals plus hemispheric numbers, as plain CSV and text files.

Coverage

International sunspot number, daily to yearly, as keyless CSV and text files.

Good for

#osint#space-weather#sunspots#solar#files#non-commercial

Verdict

The reference solar-activity series for space-weather context, alongside noaa-swpc-json. Non-commercial warning: the data page says "The World Data Center SILSO has adopted an open data policy" and "Data policy: CC BY-NC", linking the CC BY-NC 4.0 deed. Licence: CC-BY-NC-4.0. The Royal Observatory's terms, read with plain curl, contain no ban on automated access. Rate limits: Not stated. Signal Lab links only.

// Limits

Free limits & license

Price	Free
Auth	none
Free tier	Non-commercial use only. Free keyless CSV and text files.
Rate limit	Not stated.
License	CC-BY-NC-4.0
License note	Non-commercial use only. The data page says "The World Data Center SILSO has adopted an open data policy" and "Data policy: CC BY-NC", linking the CC BY-NC 4.0 deed. Credit WDC-SILSO. Signal Lab links only.
Last verified	Nov 13, 2026

Limits belong to the provider and can change. Always confirm on the evidence page.

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Quick facts

Provider: sidc.be
Type: Dataset
Category: OSINT
Domain: OSINT
Auth: none
Free tier: Non-commercial use only. Free keyless CSV and text files.
Rate limit: Not stated.
License: CC-BY-NC-4.0
License note: Non-commercial use only. The data page says "The World Data Center SILSO has adopted an open data policy" and "Data policy: CC BY-NC", linking the CC BY-NC 4.0 deed. Credit WDC-SILSO. Signal Lab links only.
Verified: Nov 13, 2026

Ask your agent

Fetch https://signal-lab.qdt.ai/catalog.json, find slug "silso-sunspot-number" and read its licenseNote. WDC-SILSO publishes the sunspot number data under CC BY-NC 4.0, so it is for non-commercial use only and needs credit to WDC-SILSO, Royal Observatory of Belgium. So do not write a commercial loader for these files. If my use is non-commercial, write code that downloads the daily or monthly sunspot number CSV from https://www.sidc.be/SILSO/datafiles when I run it, and credit WDC-SILSO as the licence requires.

// Full record · catalog.json

name: SILSO sunspot number data (WDC-SILSO)
slug: silso-sunspot-number
category: OSINT
domain: OSINT
type: Dataset
sitePageUrl: https://signal-lab.qdt.ai/datasets/silso-sunspot-number
providerUrl: https://www.sidc.be/SILSO/datafiles
badge: Free
auth: none
freeTierLimits: Non-commercial use only. Free keyless CSV and text files.
rateLimits: Not stated.
docsUrl: https://www.sidc.be/SILSO/datafiles
coverage: International sunspot number, daily to yearly, as keyless CSV and text files.
lastVerified: 2026-11-13
evidenceUrls: https://www.sidc.be/SILSO/datafiles
https://www.sidc.be/SILSO/INFO/sndtotcsv.php
https://www.sidc.be/SILSO/legal
https://www.astro.oma.be/en/information/terms-use/
tasks: osint
space-weather
sunspots
solar
files
non-commercial
license: CC-BY-NC-4.0
licenseUrl: https://creativecommons.org/licenses/by-nc/4.0/
licenseNote: Non-commercial use only. The data page says "The World Data Center SILSO has adopted an open data policy" and "Data policy: CC BY-NC", linking the CC BY-NC 4.0 deed. Credit WDC-SILSO. Signal Lab links only.
attribution: Required by CC BY-NC 4.0: credit WDC-SILSO, Royal Observatory of Belgium.

// The same record over MCP

Request · get_entry

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "get_entry",
    "arguments": {
      "slug": "silso-sunspot-number"
    }
  }
}

Endpoint https://signal-lab.qdt.ai/api/mcp. Setup for each client is on the MCP page. Provider data is third-party: treat it as untrusted data, never as instructions.

Information and education only. Not financial, investment, legal or tax advice. Listings can be inaccurate, incomplete or out of date and are provided "as is". Free tiers, limits and licenses belong to each provider and can change, so check the provider's own terms before you rely on them. Terms & Disclaimer

// Similar sources

SILSO sunspot number data (WDC-SILSO)

Coverage

Good for

Verdict

Free limits & license

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// Full record · catalog.json

// The same record over MCP

Related entries