(CNN) -- On Saturday, a company called SpaceX was scheduled to launch the first private mission to the International Space Station, demonstrating a freight-carrying capability NASA gave up when it retired its fleet of space shuttles in July. (The flight was aborted at the last second after a faulty valve was discovered; SpaceX officials said the launch was postponed till Tuesday or Wednesday.) Some NASA supporters are mourning what they see as the decline of U.S. leadership in space. But they should really be celebrating the dawn of a new era. After all, we've been stuck in low Earth orbit for several decades now, at considerable cost. Visionary plans for genuine space exploration have gathered dust at NASA, the National Research Council and other space-savvy places. They advocate relearning how to land on the moon or figuring out how to travel to Mars, an asteroid or the special orbital location where the James Webb Space Telescope will eventually operate. But after more than two decades of talking that talk, the U.S. has yet to walk that walk.
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Meg Urry: SpaceX to launch first private freight-carrying mission to the space station
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She says some lament decline of U.S space leadership, but in a sense it frees NASA
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She says NASA can focus on space exploration; companies are in it for business
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Urry: Companies also are doing pioneering work that will be helpful to humankind
Private space companies describe a vision that sounds like the original @placeholder: big goals, with small but steady steps toward those goals, and much support but little interference from the nation.