Pluto and its largest moon, Charon, posed for a solemn portrait taken
by NASA's New Horizon's probe, which is only two weeks away from its
close encounter with the dwarf planet.
The newest snapshot of Pluto and Charon shows
two icy gray circles hovering in a pitch-black void. In previous
images, the two objects often looked like highly pixelated smudges of
color — barely distinguishable as spheres. But with New Horizons only
about 10 million miles (16 million kilometers) away from Pluto (and
closing that distance by more than 30,000 miles, or 48,000 km, every
hour), the view of these unexplored worlds is getting clearer every day.
New Horizons launched in January of 2006 and has spent the last nine-plus years making its way toward Pluto
and the region of icy bodies beyond Neptune, known as the Kuiper Belt.
Although four other human-made probes have ventured past the orbit of
Neptune, none have done a close study of Pluto and its moons. Even the
Hubble Space Telescope's images of this small, dim dwarf planet are
highly pixelated and blurry. New Horizons hopes to reveal a detailed
look at the surface of Pluto, study its atmosphere and much more.
The new portrait of Pluto and Charon was taken by the Long Range
Reconnaissance Imager (LORRI) instrument onboard New Horizons. These
images are not only for scientific and aesthetic purposes, but also for
navigational ones.
With nearly 3 billion miles (4.8 billion km) between them, it takes
about 4.5 hours to send a signal from the Maryland control center to New
Horizons, Bowman said. As a result, team members have to tell the probe
what to do (such as which instruments to point at Pluto) long before
the probe actually does it. When the probe makes its close flyby of
Pluto on July 14, the team will not be able to make any last-minute
adjustments. Instead, New Horizons runs prewritten command sequences,
most of which were written years before they were executed.
The command sequences must also indicate where Pluto is located
relative to the probe, and thus where New Horizons should point its
instruments. The New Horizons team has been constantly updating that
navigational information as the probe moves closer and can obtain more
precise information about Pluto's location. Earlier this month, the team
executed a course correction to
ensure the spacecraft didn't arrive at its close encounter point too
early; that kind of miscalculation could cause the probe to take photos
of empty space instead of the dwarf planet!!!!!!!
In the next few days, the New Horizons team will be
uploading the command sequence that will guide the probe through its
historic flyby. There's also a possibility that the team will execute
another course correction.
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