The Astrodome at last has a new purpose, the managers of Reliant Park have announced. The 47-year-old flexible sports stadium will serve as a storage facility for neighboring Reliant Stadium’s new $1.2 million new-generation AstroTurf when it’s not being used on the Houston Texans’ home field. Reliant Stadium’s actual-grass-on-trays field will now be reserved for professional football; the artificial surface will be rolled out there for high-school and college football games and other events.