Overview
- Engineers built a roughly 900‑pound seamless stainless‑steel cylinder, sealed with soft indium and housed inside a larger metal bell to create an air pocket that limits moisture and corrosion over 250 years.
- America250 worked with NIST, the Library of Congress and the National Park Service to collect items from all 50 states, Washington, D.C., and five U.S. territories for a single, representative capsule.
- Contributions include a Civil War eagle feather from Wisconsin, Wright brothers fabric from Ohio, a North Atlantic right whale bone from Maine, an AI chatbot response from California, and an iPhone from America250.
- Curators rejected some proposals, like a leather football, because fragility or organic materials were judged unlikely to survive underground for 250 years, so fragile papers were boxed and put in a separate sealed compartment.
- The burial continues a U.S. time‑capsule practice stretching from 1876 to 1976 and connects to a recently unveiled 500‑year capsule in Washington, while preservation experts warn long‑term risks such as water ingress, climate effects, and institutional custody changes.