3 posts tagged “the moon”

MOON HALOES: When moonlight shines through icy clouds, the usual result is a simple pair of moondogs. But recently near Mt. Hekla, Iceland, photographer Agust Gudmundsson saw much more:

"It was a spectacular night," says Gudmundsson who needed two pictures to encompass the full display: #1, #2. "I don't know the names of all the optics in the photos, but they were fantastic."

Atmospheric optics expert Les Cowley identifies them for us: "This truly beautiful display has everything. A lunar parhelic circle courses through the moon and its dog companions. There is a 22 degree halo topped by an upper tangent arc. Higher still there is a rare lunar circumzenithal arc and something seen even less often: a lunar supralateral arc." For a quick-look summary, click here.

"In one of the photos, there is a hole in the snow," notes Gudmundsson. "It is a snowhouse where my son Atli age 12 slept this amazing night!" Can you find it?

Wed Feb 27, 2008
By Will Dunham

WASHINGTON (Reuters) - The moon's south pole region, a possible future landing site for human or robotic lunar missions, is far more rugged than had been thought, with towering peaks and deep craters, NASA said on Wednesday.

Using an Earth-based radar system in California's Mojave Desert, the U.S. space agency collected the most accurate, highest-resolution terrain mapping data to date on the moon's south pole.

NASA looked at an area around Shackleton Crater, with some terrain in perpetual darkness and other areas almost always sunlit. Scientists previously have gotten images of the area, but never in such detail, NASA said.

The Shackleton Crater rim area is a landing site candidate for a future crewed mission to the moon, NASA said. There have been previous indications water ice might exist in darkened areas of the crater, although that remains controversial.

The region has a peak towering 3.8 miles (6 km) -- rivaling North America's tallest mountain, Mount McKinley in Alaska -- and craters 2.5 miles (4 km) deep, NASA said. The scientists noted that the largest volcano on Earth -- Mauna Loa in Hawaii -- would fit easily inside these depths.

"It continues to be an area of high interest for future human landings. And this type of information is critical for us in understanding what we're getting into if we choose to land here," said Doug Cooke of NASA's Exploration Systems Mission Directorate.

Asked if the rugged terrain might give NASA pause, Cooke told reporters, "I don't think it's less attractive."

"It really calls on us to rise to the challenge of getting there, rather than having engineering constraints limit us," added NASA lunar program scientist Kelly Snook.

Cooke emphasized the importance of the possible presence of frozen ice in the region to a lunar mission.

"Having water ice gives us a source of water and gives us a source of hydrogen and oxygen, which can be made into fuel. One of the things we're interested in doing as we explore the moon and eventually Mars is to learn how to take advantage of the resources that are there to enhance the missions (and) reduce the amount of resupply and logistics from Earth," Cooke said.

Scott Hensley of the Lunar Image Team at JPL said the data could be valuable in choosing the best sites both for robotic operations on the moon in addition to human missions.

Scientists at NASA's Jet Propulsion Laboratory in Pasadena, California, obtained the data using the facility's Goldstone Solar System Radar.

Three times during a six-month period in 2006, the scientists targeted the region using Goldstone's 230-foot (70-meter) radar dish, sending a 500-kilowatt strong, 90-minute long radar stream 231,800 miles (373,000 km) to the moon.

The radar bounced off lunar terrain over an area measuring about 400 miles by 250 miles (650 km by 400 km) and the signals were reflected back to two antennas on Earth in about 2 1/2 seconds, NASA said.

By Dave Mosher
Staff Writer, Space.com
27 February 2008

Earthlings have mapped the moon's surface for the past 4,000 years, but NASA's latest view is the best yet.

Scientists have created a new map of the south lunar pole with Earth-based telescopes that is 50 times more detailed than the last version, created with data from the Clementine spacecraft in 1994.

"This data is the highest resolution and the highest accuracy that's ever made of lunar south polar region," said Scott Hensley, a scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.. Hensley and others announced the new map from the third Space Exploration Conference in Denver.

In detail of 215 square feet (20 square meters) per pixel, the map shows craters four times deeper than the Grand Canyon and hundreds of miles wide.

"It has some of the most incredible topography in the entire solar system," said Eric de Jong, also at JPL, of the region.

NASA officials said they'll use the new map to scout the rugged terrain for robot or human landing sites, as well as investigate some longstanding lunar mysteries.

Crater caches?

Many of the craters imaged have never seen direct sunlight because of their depth and location.

Such permanently shadowed areas, some scientists think, are prime spots to search for water ice or hydrogen deposits that would normally evaporate into space from solar heating. Other observations have suggested something's there.

Whether or not the deposits spacecraft have detected are water ice or hydrogen, such lunar caches could become valuable energy, air and water for visiting astronauts.

"The image[s] ... will help us figure out where we want to go," said Kelly Snook, a lunar scientist at NASA Ames in Moffett Field, Calif., of future lunar exploration missions. "They also provide us with unique ability to answer the fundamental science questions."

Snook called the moon a "unique window" to the early solar system, explaining that the lunar surface has been witness to billions of years of planetary evolution.

Radar in space

To create the new map, scientists employed NASA's Goldstone Solar System Radar facility in the Mojave Desert.

A team of scientists there bounced microwave beams off the craggy bottom of the moon when it wobbled into view — a cycle it repeats about every month. The 3-D radar data gathered with two telescopes on three separate occasions was used to compile the new map.

"We had the best opportunity in 17 years for these observations," Hensley said, explaining that the moon's wobble was exaggerated most in 2006 when the team made their observations.

Some of the features mapped are so deep that Earth's largest volcano, Mauna Loa in Hawaii, would fit neatly inside some of the craters, Hensley said.

"It's quite impressive topography that we have here," he said.

Better maps to come

Doug Cooke at NASA Headquarters in Washington, D.C. said NASA's upcoming Lunar Reconnaissance Orbiter (LRO) will soon map the entire moon in even more detail in the next few years.

"We will be getting better data," Hensley said of LRO, "...but this [map] is a big step in our understanding of this very interesting place."

All of the information should be a boon to astronauts who might visit the rough terrain of south lunar pole in the future, but in either case Hensley said simply sending spacecraft won't allow us to fully understand our lunar companion.

"This type of information is critical for us in understanding what we're getting into," Cooke said. "... [but] to really understand it, it takes going there and seeing first-hand what you've got."