🌌 Stellar Passphrase Scheme: “Celestial Key Encoding (CKE)”

Store secrets in celestial bodies!

🔐 Overview

• Purpose: Store a small amount of secret data (e.g., a passphrase or seed phrase) using the sky as the medium.

• Security: Based on:

  • Sky visibility (time & location)

  • Star catalog selection

  • Custom encoding rules

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🧩 1. Components of the Scheme

✅ Star Catalog

• Use a known public catalog (e.g. Hipparcos, Gaia DR2)

• Filter down to naked-eye or telescope-visible stars (say, mag < 6.0)

✅ Parameters to Encode Bits:

Each selected star can encode 1-2 bits using these properties:

Property | Bit Representation

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Brightness (magnitude) | 0 = dim, 1 = bright

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Relative Position | Based on N/S or E/W of another star

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Angular Distance | If within certain arcminutes = 1, else 0

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Altitude at specific time | Above 45° = 1, else 0

You can define these thresholds to create a bitstream.

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🧠 2. Encoding a Passphrase

Let’s say your passphrase is:

“STELLAR-VAULT”

Convert it to binary:

01010011 01010100 01000101 01001100 01001100 01000001 01010010 00101101 01010110 01000001 01010101 01001100 01010100

Total: 104 bits

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🪐 3. Mapping Bits to Stars

Choose 104 stars from the catalog based on a secret rule (e.g., brightest stars above 45° altitude from latitude 37°N on a specific date). Then assign:

• Bit 1 = whether the star is north of celestial equator

• Bit 2 = whether the magnitude < 3.0

• Or assign 1 bit per star using custom condition

Store the map:

Star ID: HIP 32349 (Sirius)
Rule: mag < 1.0 → 1

Star ID: HIP 24436 (Betelgeuse)
Rule: declination > 0° → 1
...

This becomes your decoder’s lookup table, but not shared publicly — only the intended reader knows which rules apply.

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🧮 4. Decoding Procedure (for authorized user)

To decode the passphrase:

1. Use telescope or software (e.g. Stellarium) to identify the star list and observe current positions/magnitudes.

2. Apply bit extraction rules to each star.

3. Reconstruct the binary stream → convert to ASCII → get passphrase.

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🛡️ 5. Security Enhancements

🧭 Time-Based Lock:

• The stars must be observed on a specific UTC date/time when their positions align just right.

🌍 Location-Based Lock:

• Star visibility differs by Earth location → only decodable at latitude X, longitude Y.

🔁 Catalog Hash Lock:

• Use a hash of the catalog subset (e.g., SHA256 of star IDs) as a checksum to verify integrity.

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Stellar Keyfile (Private)

date:       2025-12-21T02:00Z
location:   37.7749° N, 122.4194° W
catalog:    Hipparcos v2.0
star_count: 104
bit_rule:
  - if mag < 2.5 → 1 else 0
  - if dec > 0° → 1 else 0
order: based on ascending RA

This becomes the key to decode the sky on that date, from that place.

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🎯 Summary

Feature            |  Details
Storage capacity   |  Low (~100–200 bits)
Write access       |  Manual encoding via star list
Read access        |  Only with star map + decoding rules
Security           |  Based on time, location, hidden mapping rules
Use case           |  Cold storage of keys, passphrases, secure messages