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The Lunar Reconnaissance Orbiter has been orbiting the Moon since 2009,

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and during this time, NASA videos have explored numerous aspects of the spacecraft.

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But one question keeps popping up . . . How do you drive that thing?

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Well, first imagine a souped-up racecar.

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Picture revving up that engine, wind flowing over its streamlined body,

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turning the wheel around sharp hairpin turns . . .

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Got that image?  Great!  It's nothing like that.

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Now picture playing an arcade game,

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using your controls to fly a spacecraft around at crazy warp speeds.

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Yeah, it's nothing like that either.

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Flying LRO involves computer science, satellite technology, and a great deal of teamwork.

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Not as cool as what you might have imagined,

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but it's still an impressive and sophisticated technological operation.

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For starters, LRO is controlled by a group of engineers - the Mission Operations Team.

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They work out of a control room, called the Mission Operations Center.

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All commands to the spacecraft originate from this control room

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and are sent through antennas around the globe.

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And here's where we reveal the big secret.

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Most spacecraft operations are actually handled using preprogrammed commands.

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Every day a team member builds a "command load" using specialized computer software.

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This is essentially a time-sensitive schedule of commands, such as thruster maneuvers,

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starting and stopping its cameras, and pointing the spacecraft to a selected target.

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These command loads are then activated on board by the "Single Board Computer,"

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which talks to the electronics and microprocessors in LRO's instruments.

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Many operations require real-time monitoring.

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In some cases, team members simply observe as the preprogrammed commands execute.

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At other times, the team must initiate a specific command for an action to occur on board.

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One event requiring real-time monitoring is a lunar eclipse.

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A lunar eclipse could mean trouble for LRO since it's solar-powered.

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To prevent damage from the frigid temperatures, prior to the eclipse,

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the spacecraft will spend about fourteen hours heating up.

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Nearly all instruments will be turned off as well to preserve battery power.

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Once out of the darkness, commands are given to reconfigure the spacecraft.

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If an emergency occurs during spaceflight,

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the Single Board Computer can put LRO into a "safe mode."

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This maintains safe temperatures and electricity

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until the team can contact the satellite and determine the problem.

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One final aspect to operating this spacecraft involves its reaction wheels.

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And no, these don't have spinners or flashy rims.

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Reaction wheels help orient a spacecraft through managing angular momentum.

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An easy way to think about this concept

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is how it's easier for a bicycle to stay upright when the wheels are turning.

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On LRO there are four reaction wheels constantly spinning.

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By making very small changes in their speeds, the satellite is kept pointed toward the moon.

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Larger changes in the wheel speeds can get the spacecraft to point in different directions -

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perhaps toward Earth to take a picture or the stars for instrument calibration.

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Over time, the reaction wheels spin faster and faster

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as they keep the instruments pointing at the moon,

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causing the angular momentum to steadily increase.

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As a result, every few weeks, a decrease in the angular momentum is needed.

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This is done by firing thrusters,

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as that gets the reaction wheels to compensate and spin more slowly.

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This process is called a momentum unload maneuver.

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So as you can see, operating a lunar spacecraft is a different sort of driving experience.

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You may have been thinking this . . . 

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but it actually involves this.

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