n Nov. 5, a SpaceX rocket roared into the heavens from Cape Canaveral, Florida, carrying a boxy, 5,000-pound, antenna-studded satellite toward its destination 12,500 miles away, up in what's known as medium Earth orbit. From that distant vantage point, it'll soon beam signals that will help you find your way to a friend's new house out in the suburbs or a vacation destination six hours down the coast.

If you stop at an ATM along the way to grab some cash, those signals will also help the bank know your withdrawal happened after your direct deposit paycheck refreshed your finances. They'll be a factor, too, in whether your cellphone call to your friend, or the rental agent, goes through without garbling or fading.

Those signals will be coming from a GPS III satellite, the newest member of a constellation of satellites that have become a constant and intimate presence in our daily lives. With GPS III, we're getting not just new boxes in the sky, but a series of upgrades that'll help make the system better for all of us here on Earth. And we'll need it.

The Global Positioning System has become vital to nearly all sectors of the country's critical infrastructure, with much of its work happening behind the scenes, and likely to a much greater extent than you realize. GPS tells us where we are and helps us get where we're going, but a core aspect of the technology is when -- the timing of, well, more or less a zillion things. It plays a critical role in financial transactions and stock trades, forecasting the weather, monitoring earthquakes and keeping the power grid humming.