DNA Ark: Encoding A Cryptographic Framework for a National Library into DNA as the First Step Toward an Earth Memory Project for Multi-Planetary Civilization

The preservation of human knowledge is one of the fundamental challenges of long‑term civilization. Modern digital storage technologies remain fragile, energy‑dependent, and vulnerable to planetary‑scale disruptions. The rapid growth of digital data demands storage media with higher density, longevity, and security. Synthetic DNA has emerged as a promising alternative to conventional electronic storage due to its extraordinary information density and long-term stability. However, current DNA data storage systems primarily focus on encoding efficiency and biochemical constraints, while security and cryptographic integrity remain underexplored. Synthetic DNA offers an alternative storage medium with extraordinary information density and millennia‑scale durability. Here we introduce DNA Ark, a cryptographically secure DNA storage framework designed as part of the Earth Memory Project, a long‑term initiative to preserve human knowledge beyond planetary risks. Here we introduce hiDNA, a cryptographic DNA storage architecture that integrates adaptive encoding, cryptographic key generation, and biochemical sequence optimization into a unified framework. The encoding algorithm employs a key-dependent nucleotide mapping strategy that minimizes homopolymers, maintains balanced GC content (40–60%), and ensures compatibility with current DNA synthesis and sequencing technologies. In this work, using a computational simulation, we encoded a dataset equivalent to 2.6 million books, corresponding to the approximate scale of a national library. The hiDNA framework successfully generated synthesis-compatible DNA sequences while maintaining biochemical constraints and the integrity of cryptographic encoding. Information density analysis indicates that such archives could theoretically be stored in sub-gram quantities of DNA, highlighting the feasibility of ultra-compact molecular knowledge repositories. The proposed hiDNA encoding framework integrates adaptive cryptographic mapping, biochemical sequence optimization, and robust error correction to convert digital information into synthesis‑compatible DNA sequences securely. Our system enables the transformation of large‑scale cultural archives into molecular storage while maintaining compatibility with existing sequencing technologies. Our architecture enables secure storage of digital information in synthetic DNA molecules while maintaining compatibility with existing synthesis and sequencing technologies. The hiDNA model establishes the foundation for a DNA cryptography standard and opens a pathway toward secure biological data storage systems. This work establishes the foundation for DNA‑native cryptographic storage and proposes a new paradigm in which human knowledge can be archived as a civilization seed for future generations. In the long term, such archives could enable the creation of a Library of Earth for Mars, supporting the development of a multi‑planetary civilization.