CREATE TABLE table_203_281 (id DECIMAL, "season" DECIMAL, "pitcher" TEXT, "decision" TEXT, "final\ score" TEXT, "opponent" TEXT, "location" TEXT)

who was the first astro to be the opening day pitcher in the astrodome ?
SELECT "pitcher" FROM table_203_281 WHERE "location" = 'astrodome' ORDER BY "season" LIMIT 1
SELECT "pitcher" FROM "table_203_281" WHERE "location" = 'astrodome' ORDER BY "season" NULLS FIRST LIMIT 1