And yet something persisted.

The values persisted.

The emphasis on education persisted.

The sense that Cherokee people had a claim on the fullest possible participation in the intellectual life of the century they found themselves in — that persisted.

Mary Ross was the specific human being in whom that persistence produced its most striking result.

A mathematician who computed planetary trajectories.

A woman who in 1942 walked into one of the most advanced aerospace companies in the world and stayed for thirty-one years.

A Cherokee woman who in 2004, at ninety-six years old, walked into the Smithsonian’s National Museum of the American Indian on the National Mall and stood in Cherokee regalia in the house that her people’s long persistence had finally produced.

The full arc of her life is the arc from Park Hill, Oklahoma to the outer solar system — the distance traveled in one life between a birth in the year of Oklahoma statehood and a death in the year that Mars rovers were sending home photographs from another planet.

She covered that distance with mathematics.

The mathematics holds.