70-meter antenna at the Goldstone complex in California. /// The 70-meter (230-foot) diameter antenna is the largest, and therefore most sensitive, DSN antenna, and is capabile of tracking a spacecraft travelling more than 16 billion kilometers (10 billion miles) from Earth. Image Credit: NASA
High Resolution NASA Radar … Maps The Moon
NASA's Jet Propulsion Laboratory has recently released new high-resolution radar maps of the Moon's south pole. The mapping technique is unique in that it uses digital radar information gleaned from one array of the most sophisticated radar antennae’s in NASA’s arsenal of sensing equipment.
The antenna’s in the array measure three-quarters the size of a football field. From the Mojave desert in California here on the Oblate Spheroid, the antennae send a 500-kilowatt strong, 90-minute long radar stream 231,800 miles to the Moon … and back. The information is then processed with computers at JPL in Pasadena in order to develop detail maps of the Moon’s surface for possible landing sites of possible future Lunar exploration missions. This technique is second only to actually launching a satellite with sophisticated camera equipment and surface sensors.
Digital Elevation Map of Lunar South Pole - Image brightness is generated from the strength of the radar echoes that are bounced of the lunar surface and the color represents the elevation. This map covers an area of 650 kilometers (400 miles) by 450 kilometers (280 miles) with an elevation measurement every 40 meters (130 feet). Image Credit: NASA
This excerpted from Science @ NASA website -
New Radar Maps of the Moon
Science @ NASA - February 29, 2008
NASA has obtained new high-resolution radar maps of the Moon's south pole--a region the space agency is considering as a landing site when astronauts return to the Moon in the years ahead.
"We now know the south pole has peaks as high as Mt. McKinley and crater floors four times deeper than the Grand Canyon," says Doug Cooke, deputy associate administrator for the Exploration Systems Mission Directorate at NASA Headquarters. "These data will be an invaluable tool for advance planning of lunar missions."
New radar imagery of the lunar south pole. The movie simulates solar illumination over the course of a complete lunar day. Video Credit: NASA
Scientists at NASA's Jet Propulsion Laboratory collected the data using the Goldstone Solar System Radar located in California's Mojave Desert. Three times in 2006, JPL scientists targeted the moon's south polar region using Goldstone's 70-meter radar dish. The antenna, three-quarters the size of a football field, sent a 500-kilowatt strong, 90-minute long radar stream 231,800 miles to the Moon. The radar illuminated the rough-hewn lunar surface over an area measuring about 400 by 250 miles. Signals were reflected back to two of Goldstone's 34-meter antennas on Earth. Scientists have been analyzing the echoes ever since, and the data were released by NASA for the first time this week.
NASA has used the data to make a VR movie of a Moon landing from the point of view of the astronaut. Click here to watch. Animation Credit: NASA
"I have not been to the Moon, but this imagery is the next best thing," says Scott Hensley, a scientist at JPL and lead investigator for the study. "With these data we can see terrain features as small as a house without even leaving the office."
NASA is eying the Moon's south polar region as a possible site for future outposts. The location has many advantages; for one thing, there is evidence of water frozen in deep dark south polar craters. Water can be split into oxygen to breathe and hydrogen to burn as rocket fuel--or astronauts could simply drink it. Planners are also looking for "peaks of eternal light." Tall polar mountains where the sun never sets might be a good place for a solar power station.
These are the highest-resolution maps to date. The best images, previously, were generated by the Clementine spacecraft, which could resolve lunar terrain features near the south pole at 1 kilometer per pixel. The JPL radar maps are 50 times more detailed.
As wonderful as they are, however, these images will pale in comparison to next-generation photos from NASA's Lunar Reconnaissance Orbiter. The spacecraft is scheduled to launch in late 2008 and its camera will beam back photos of the moon with details as small as 1 meter.
"The south pole of the Moon," says Cooke, is going to be "a beautiful place to explore."
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