New Horizons

Today is July 14, 2015. Yesterday the New Horizons spacecraft was a million miles from Pluto. Today, New Horizons will buzz the dwarf planet far faster than any bullet. At 7:50 AM EDT (11:50 UTC), New Horizons will be 7800 miles from Pluto.

New Horizons was launched on January 19, 2006, at a velocity of 36,373 mph. It is the fastest spacecraft to ever leave Earth orbit, 100 times faster than a jetliner. The spacecraft proceeded to Jupiter where the giant planet’s enormous gravity boosted New Horizons’ speed to over 52,000 mph. The boost in speed shaved three years off the travel time to Pluto.

The spacecraft has been climbing out of the Sun’s gravity well, and that means it has been slowing down ever since it left Jupiter. But it still has a lot of speed; it is traveling, even now, at over 30,000 mph.

New Horizons hibernated for most of its journey to Pluto. It was brought back online on December 6, 2014. It is awake now and sending back photos of the dwarf planet as it approaches its encounter. The piano-sized spacecraft will be hurtling past Pluto so fast it won’t have time to send images back to Earth during the flyby. The spacecraft will be busy taking photos and doing other science; aiming its antenna at Earth and sending back data would take precious time that could be used to take photos. Sending all the data back to Earth will take months. We will have to wait until after the encounter to get images of Pluto. That is, if New Horizons survives its encounter with Pluto.

There are five moons of Pluto that we know of, and there may be more that are too small for us to see. At 30,000 mph a piece of space rock the size of a grain of rice would blast a hole all the way through New Horizons. All we can do now is cross our fingers and hope that New Horizons will phone home. If it does, and if it is in good shape, the little spacecraft will continue on to the Kuiper Belt where it will make more observations. Its mission is scheduled to end in 2026 – twenty years after its launch.