A Century Hence

(Lancaster Castle and a Morecambe Bay sunset, symbolizing history and the passage of time.)

"Wildcat."

An expedition to 100,000,000 AD returns and reports that a certain location will remain stable;

Team A is projected into the twenty-first century;

that team observes and records data;

its members place their data in an inert box enclosed in a large block of reinforced concrete at the stable location;

mixing radioactive material with a long half-life in the concrete will make the block easier to locate;

Team B is projected to 100,000,000 AD, acquires the data and returns to the twentieth century;

Team A joins the base in the Jurassic a century after it was founded.