We are just two weeks from our first up-close encounter with Pluto. New Horizons’ mission planners have completed the last of three planned targeting maneuvers to line up the spacecraft’s approach.
The 23-second thruster burn added about one-half mile per hour to its velocity. On July 14, New Horizons will rocket past Pluto at 32,500 mph at a distance of 7,750 miles above its surface.
This latest adjustment doesn’t sound like much, but it makes a difference over these last 14 days. Without it, New Horizons would arrive at Pluto about 20 seconds late and more than 100 miles off-target according to New Horizons Mission Design Lead Yanping Guo.
Timing is imperative
Is 20 seconds that big of a deal? It is when New Horizons’ observation commands are stored inside its computers and programmed to execute at a certain time.
Issuing these commands via a radio signal from Earth is out of the question. A radio signal from Earth takes four and a half hours to reach Pluto. That’s why the New Horizons team stored the commands on the spacecraft’s computers.
New Horizons detects frozen methane
Astronomers have known about frozen methane on Pluto since first observing it in 1972. But, it is the first time New Horizons has detected it.
New Horizons Surface Composition team leader Will Grundy explains what New Horizons will look for later this month. “Soon we will know if there are differences in the presence of methane ice from one part of Pluto to another.”
NASA also released another timelapse of Pluto and its largest moon, Charon. The video below shows New Horizons approaching the Pluto system from a distance of about 35 million miles to 14 million miles.
Note the contrast between Pluto’s bright northern hemisphere and a dark band of material near its equator.
Charon’s dark polar region is even more pronounced than in earlier images.
New Horizons is less than 11 million miles away from Pluto. The spacecraft is in great shape and is on target for its July 14 flyby. New Horizons will show us Pluto like we’ve never seen it before.
Image credit: NASA