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Space Station Crew Enjoys Eye-Level View of Perseid Meteor Shower

Copyright NASA

With the bright moon that was out on the evening of August 13, many astronomy buffs were not able to fully appreciate the spectacular Perseid meteor shower going on in the night sky. From the International Space Station, however, astronaut Ron Garan had a front seat view as part of the Crew Earth Observations, or CEO, investigation.

Using a Nikon D3S digital camera with a 22 mm lens, Garan captured a stunning photo of one of the Perseid meteors streaking through Earth’s atmosphere. You can see part of the space station’s solar array in the image, allowing the viewer to share in the unique perspective of the crew from low Earth orbit. This photograph will add to the CEO investigation’s collection of hundreds of thousands of Earth images.

The astronaut photography for CEO supports global research, according to William Stefanov, chief scientist for the Engineering and Science Contract Group supporting the Astromaterials Research and Exploration Science Directorate at NASA’s Johnson Space Center. “The inclined equatorial orbit of the station, and having ‘humans in the loop,’ makes it a useful and unique platform in comparison to unmanned polar-orbiting sensor systems. From the space station, data can [...]

New NASA Designs for a Reusable Manned Deep-Space Craft

Copyright NASA/HobbySpace

This tubular spacecraft could serve as a reusable vehicle for lunar and deep-space missions, holding a crew of six and enough supplies for a two-year expedition.

Dubbed Nautilus-X, for “Non-Atmospheric Universal Transport Intended for Lengthy United States eXploration,” this craft could be built in orbit and ready for space missions by 2020, according to a briefing by NASA’s Future In Space Operations group.

It would be assembled from expandable structures, such as the inflatable habitats proposed by Bigelow Aerospace. It would also contain a ring centrifuge to provide partial gravity, and radiation-mitigation systems that could include tanks of water or liquid hydrogen slush, reports the website HobbySpace.com.

LRO Creating Unprecedented Topographic Map of Moon

Copyright NASA

“This dataset is being used to make digital elevation and terrain maps that will be a fundamental reference for future scientific and human exploration missions to the moon,” said Dr. Gregory Neumann of NASA’s Goddard Space Flight Center in Greenbelt, Md. “After about one year taking data, we already have nearly 3 billion data points from the Lunar Orbiter Laser Altimeter on board the LRO spacecraft, with near-uniform longitudinal coverage. We expect to continue to make measurements at this rate through the next two years of the science phase of the mission and beyond. Near the poles, we expect to provide near-GPS-like navigational capability as coverage is denser due to the spacecraft’s polar orbit.” Neumann will present the map at the American Geophysical Union meeting in San Francisco December 17.

The Lunar Orbiter Laser Altimeter (LOLA) works by propagating a single laser pulse through a Diffractive Optical Element that splits it into five beams. These beams then strike and are backscattered from the lunar surface. From the return pulse, the LOLA electronics determines the time of flight which, accounting for the speed of light, provides a precise measurement of the range from the spacecraft to the lunar [...]

Study Links Fresh Mars Gullies to Carbon Dioxide

Copyright NASA

A growing bounty of images from NASA’s Mars Reconnaissance Orbiter reveals that the timing of new activity in one type of the enigmatic gullies on Mars implicates carbon-dioxide frost, rather than water, as the agent causing fresh flows of sand.

Researchers have tracked changes in gullies on faces of sand dunes in seven locations on southern Mars. The periods when changes occurred, as determined by comparisons of before-and-after images, overlapped in all cases with the known winter build-up of carbon-dioxide frost on the dunes. Before-and-after pairs that covered periods only in spring, summer and autumn showed no new activity in those seasons.

“Gullies that look like this on Earth are caused by flowing water, but Mars is a different planet with its own mysteries,” said Serina Diniega, lead author of a report on these findings in the November issue of the journal Geology. She analyzed these gullies while a graduate student at the University of Arizona, Tucson, and recently joined NASA’s Jet Propulsion Laboratory, Pasadena. “The timing we see points to carbon dioxide, and if the mechanism is linked to carbon-dioxide frost at these dune gullies, the same could be true for other gullies on Mars.”

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Survey Suggests Earth-Sized Planets Are Common

Copyright NASA

Nearly one in four stars similar to the sun may host planets as small as Earth, according to a new study funded by NASA and the University of California.

The study is the most extensive and sensitive planetary census of its kind. Astronomers used the W.M. Keck Observatory in Hawaii for five years to search 166 sun-like stars near our solar system for planets of various sizes, ranging from three to 1,000 times the mass of Earth. All of the planets in the study orbit close to their stars. The results show more small planets than large ones, indicating small planets are more prevalent in our Milky Way galaxy.

“We studied planets of many masses — like counting boulders, rocks and pebbles in a canyon — and found more rocks than boulders, and more pebbles than rocks. Our ground-based technology can’t see the grains of sand, the Earth-size planets, but we can estimate their numbers,” said Andrew Howard of the University of California, Berkeley, lead author of the new study. “Earth-size planets in our galaxy are like grains of sand sprinkled on a beach — they are everywhere.”

The study appears in the Oct. 29 issue of [...]

A Snapshot of Sea Ice

Copyright NASA

How does the Aqua satellite “see” sea ice? Microwaves. Everything on Earth’s surface — including people — emits microwave radiation, the properties of which vary with the emitter, thereby allowing the AMSR-E microwave sensor on Aqua to map the planet.

Ice emits more microwave radiation than water, making regions of the ocean with floating ice appear much brighter than the open ocean to the AMSR-E sensor. This difference allows the satellite to capture a sea ice record year-round, through cloud cover and the months of polar night. Continuous records are important because sea ice is dynamic. Besides melting and freezing, the ice moves with wind and currents which can cause it to split or pile up.

“The data from AMSR-E and other NASA satellites are critical for understanding the coupling between sea ice and the ocean and atmosphere,” said Tom Wagner, Cryosphere program manager at NASA Headquarters in Washington. “It’s important for us to understand these connections to improve our predictive models of how the planet will change.”

The Arctic sea ice is a major factor in the global climate system. The ice cools the planet by reflecting sunlight back into space. It also helps drive ocean [...]

Emerging Technologies May Fuel Revolutionary Launcher

Copyright NASA

As NASA studies possibilities for the next launcher to the stars, a team of engineers from Kennedy Space Center and several other field centers are looking for a system that turns a host of existing cutting-edge technologies into the next giant leap spaceward.

An early proposal has emerged that calls for a wedge-shaped aircraft with scramjets to be launched horizontally on an electrified track or gas-powered sled. The aircraft would fly up to Mach 10, using the scramjets and wings to lift it to the upper reaches of the atmosphere where a small payload canister or capsule similar to a rocket’s second stage would fire off the back of the aircraft and into orbit. The aircraft would come back and land on a runway by the launch site.

Engineers also contend the system, with its advanced technologies, will benefit the nation’s high-tech industry by perfecting technologies that would make more efficient commuter rail systems, better batteries for cars and trucks, and numerous other spinoffs.

It might read as the latest in a series of science fiction articles, but NASA’s Stan Starr, branch chief of the Applied Physics Laboratory at Kennedy, points out that nothing in the design [...]

Kepler Mission Discovers Two Planets Transiting the Same Star

Copyright NASA

NASA’s Kepler spacecraft has discovered the first confirmed planetary system with more than one planet crossing in front of, or transiting, the same star.

The transit signatures of two distinct planets were seen in the data for the sun-like star designated Kepler-9. The planets were named Kepler-9b and 9c. The discovery incorporates seven months of observations of more than 156,000 stars as part of an ongoing search for Earth-sized planets outside our solar system. The findings will be published in Thursday’s issue of the journal Science.

Kepler’s ultra-precise camera measures tiny decreases in the stars’ brightness that occur when a planet transits them. The size of the planet can be derived from these temporary dips.

The distance of the planet from the star can be calculated by measuring the time between successive dips as the planet orbits the star. Small variations in the regularity of these dips can be used to determine the masses of planets and detect other non-transiting planets in the system.

In June, mission scientists submitted findings for peer review that identified more than 700 planet candidates in the first 43 days of Kepler data. The data included five additional candidate systems that appear [...]

Pulverized Planet Dust May Lie Around Double Stars

Copyright NASA

Tight double-star systems might not be the best places for life to spring up, according to a new study using data from NASA’s Spitzer Space Telescope. The infrared observatory spotted a surprisingly large amount of dust around three mature, close-orbiting star pairs. Where did the dust come from? Astronomers say it might be the aftermath of tremendous planetary collisions.

“This is real-life science fiction,” said Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass. “Our data tell us that planets in these systems might not be so lucky — collisions could be common. It’s theoretically possible that habitable planets could exist around these types of stars, so if there happened to be any life there, it could be doomed.”

Drake is the principal investigator of the research, published in the Aug.19 issue of the Astrophysical Journal Letters.

The particular class of binary, or double, stars in the study are about as snug as stars get. Named RS Canum Venaticorums, or RS CVns for short, they are separated by only about two million miles (3.2 million kilometers), or two percent of the distance between Earth and our sun. The stellar pairs orbit around each other every few [...]

Sailing Among the Stars

Copyright NASA

This fall, NASA researchers will move one step closer to sailing among the stars.

Astrophysicists and engineers at the Marshall Space Flight Center in Huntsville, Ala., and the Ames Research Center in Moffett Field, Calif., have designed and built NanoSail-D, a “solar sail” that will test NASA’s ability to deploy a massive but fragile spacecraft from an extremely compact structure. Much like the wind pushing a sailboat through water, solar sails rely on sunlight to propel vehicles through space. The sail captures constantly streaming solar particles, called photons, with giant sails built from a lightweight material. Over time, the buildup of these particles provides enough thrust for a small spacecraft to travel in space.

Many scientists believe that solar sails have enormous potential. Because they take advantage of sunlight, they don’t require the chemical fuel that spacecraft currently rely on for propulsion. Less fuel translates into lower launch weight, lower costs and fewer logistical challenges. Solar sails accelerate slowly but surely, capable of eventually reaching tremendous speeds. In fact, most scientists consider solar sailing the only reasonable way to make interstellar travel a reality.

Of course, it’s not as easy as it sounds.

For scientists to really [...]