[meteorite-list] New Horizons Sees More Detail as It Draws Closer to Pluto

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed, 27 May 2015 17:07:40 -0700 (PDT)
Message-ID: <201505280007.t4S07e6c012517_at_zagami.jpl.nasa.gov>

http://pluto.jhuapl.edu/News-Center/News-Article.php?page=20150527

New Horizons Sees More Detail as It Draws Closer to Pluto
May 27, 2015

What a difference 20 million miles makes! Images of Pluto from NASA's
New Horizons spacecraft are growing in scale as the spacecraft
approaches its mysterious target. The new images, taken May 8-12 using a
powerful telescopic camera and downlinked last week, reveal more detail
about Pluto's complex and high-contrast surface.

The images were taken from just under 50 million miles (77 million
kilometers) away, using the Long-Range Reconnaissance Imager (LORRI) on
New Horizons. Because New Horizons was approximately 20 million miles
closer to Pluto in mid-May than in mid-April, the new images contain
about twice as many pixels on the object as images made in mid-April.

A technique called image deconvolution sharpens the raw, unprocessed
pictures beamed back to Earth. In the April images, New Horizons
scientists determined that Pluto has broad surface markings - some
bright, some dark - including a bright area at one pole that may be a
polar cap. The newer imagery released here shows finer details.
Deconvolution can occasionally produce spurious details, so the finest
details in these images will need confirmation from images to be made
from closer range in coming weeks.

[Images]

These images show Pluto in the latest series of New Horizons Long Range
Reconnaissance Imager (LORRI) photos, taken May 8-12, 2015, compared to
LORRI images taken one month earlier. In the month between these image
sets, New Horizons' distance to Pluto decreased from 68 million miles
(110 million kilometers) to 47 million miles (75 million kilometers), as
the spacecraft speeds toward a close encounter with the Pluto system in
mid-July.

The April images are shown on the left, with the May images on the
right. All have been rotated to align Pluto's rotational axis with the
vertical direction (up-down), as depicted schematically in the center
panel. Between April and May, Pluto appears to get larger as the
spacecraft gets closer, with Pluto's apparent size increasing by
approximately 50 percent. Pluto rotates around its axis every 6.4 Earth
days, and these images show the variations in Pluto's surface features
during its rotation.

These images are displayed at four times the native LORRI image size,
and have been processed using a method called deconvolution, which
sharpens the original images to enhance features on Pluto. Deconvolution
can occasionally add "false" details, so the finest details in these
pictures will need to be confirmed by images taken from closer range in
the next few weeks. All of the images are displayed using the same
linear brightness scale.

"These new images show us that Pluto's differing faces are each
distinct; likely hinting at what may be very complex surface geology or
variations in surface composition from place to place," said New
Horizons Principal Investigator Alan Stern, of the Southwest Research
Institute in Boulder, Colorado. "These images also continue to support
the hypothesis that Pluto has a polar cap whose extent varies with
longitude; we'll be able to make a definitive determination of the polar
bright region's iciness when we get compositional spectroscopy of that
region in July."

The images New Horizons returns will dramatically improve in coming
weeks as the spacecraft speeds closer to its July 14 encounter with the
Pluto system, covering about 750,000 miles per day.

"By late June the image resolution will be four times better than the
images made May 8-12, and by the time of closest approach, we expect to
obtain images with more than 5,000 times the current resolution," said
Hal Weaver, the mission's project scientist at the Johns Hopkins
University Applied Physics Laboratory (APL) in Laurel, Maryland.

Following a January 2006 launch, New Horizons is currently about 2.95
billion miles from home; the spacecraft is healthy and all systems are
operating normally.

APL designed, built, and operates the New Horizons spacecraft, and
manages the mission for NASA's Science Mission Directorate. SwRI leads
the science team, payload operations and encounter science planning. New
Horizons is part of the New Frontiers Program managed by NASA's Marshall
Space Flight Center in Huntsville, Alabama.
Received on Wed 27 May 2015 08:07:40 PM PDT