Space Station Live: Deploying Cubesats from the Station

NASA PAO Officer Amiko Kauderer talks to Michael Johnson, NanoRacks Chief Technology Officer, about the installation of the CubeSat deployer in the Japanese Experiment Module Airlock. The installation work is in preparation for the upcoming deployment of several tiny satellites.

Space to Ground - 1/31/14

NASA's Space to Ground is your weekly update on what's happening aboard the International Space Station. Got a question or comment?

Astronaut Mike Hopkins: Workout in Space 1

Astronaut Mike Hopkins, a lifelong athlete, worked closely with his strength and conditioning coach Mark Guilliams to develop these specially-designed workouts in orbit. Shown here, Hopkins is using the Advanced Resistive Exercise Device to perform this challenging workout. (100 Pull Ups, Push Ups, Sit Ups and Air Squats each.)

As part of his mission, Hopkins is a participant in a number of going medical studies and research experiments.

Pro K is one area of research Mike is helping with. For this study, the astronauts eat a low protein diet in an effort to minimize bone mineral loss. This will not only help future astronauts on long duration missions, but given the dietary trends in the U.S., this research will have direct public health significance helping us better understand protein-rich diets. Learn more about Pro K: http://www.nasa.gov/mission_pages/sta...

Numerous benefits are already being realized from space station science such as vaccine development research, imagery that aids disaster relief and farming, and education programs that inspire future scientists, and engineers are just some examples. To learn more about benefits from ISS, visit: http://www.nasa.gov/iss-science

Staying healthy is important for all astronauts going to space, but lifelong fitness is particularly important to Mike. To follow along with his workouts and other Astronaut workouts and activities, check out: http://www.facebook.com/TrainAstronaut

NASA's LRO Snaps a Picture of NASA's LADEE Spacecraft

With precise timing, the camera aboard NASA's Lunar Reconnaissance Orbiter (LRO) was able to take a picture of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft as it orbited our nearest celestial neighbor. The Lunar Reconnaissance Orbiter Camera (LROC) operations team worked with its LADEE and LRO operations counterparts to make the imaging possible.
LADEE is in an equatorial orbit (east-­to-­west) while LRO is in a polar orbit (south-­to-­north). The two spacecraft are occasionally very close and on Jan. 15, 2014, the two came within 5.6 miles (9 km) of each other. As LROC is a push-broom imager, it builds up an image one line at a time, so catching a target as small and fast as LADEE is tricky. Both spacecraft are orbiting the moon with velocities near 3,600 mph (1,600 meters per second), so timing and pointing of LRO must be nearly perfect to capture LADEE in an LROC image.
LADEE passed directly beneath the LRO orbit plane a few seconds before LRO crossed the LADEE orbit plane, meaning a straight down LROC image would have just missed LADEE. The LADEE and LRO teams worked out the solution: simply have LRO roll 34 degrees to the west so the LROC detector (one line) would be in the right place as LADEE passed beneath.
As planned at 8:11 p.m. EST on Jan. 14, 2014, LADEE entered LRO’s Narrow Angle Camera (NAC) field of view for 1.35 milliseconds and a smeared image of LADEE was snapped. LADEE appears in four lines of the LROC image, and is distorted right­to­left. What can be seen in the LADEE pixels in the NAC image?
Step one is to minimize the geometric distortion in the smeared lines that show the spacecraft. However, in doing so the background lunar landscape becomes distorted and unrecognizable (see above). The scale (dimension) of the NAC pixels recording LADEE is 3.5 inches (9 cm), however, as the spacecraft were both moving about 3,600 mph (1,600 meters per second) the image is blurred in both directions by around 20 inches (50 cm). So the actual pixel scale lies somewhere between 3.5 inches and 20 inches. Despite the blur it is possible to find details of the spacecraft, which is about 4.7 feet (1.9 meters) wide and 7.7 feet (2.4 meters) long. The engine nozzle, bright solar panel and perhaps a star tracker camera can be seen (especially if you have a correctly oriented schematic diagram of LADEE for comparison).
LADEE was launched Sept. 6, 2013. LADEE is gathering detailed information about the structure and composition of the thin lunar atmosphere and determining whether dust is being lofted into the lunar sky.
LRO launched Sept. 18, 2009. LRO continues to bring the world astounding views of the lunar surface and a treasure trove of lunar data.
NASA’s Goddard Space Flight Center in Greenbelt, Md., manages the LRO mission. NASA's Ames Research Center in Moffett Field, Calif., manages the LADEE mission.

NASA Ramps Up Space Launch System Sound Suppression Testing

The first round of acoustic tests on a scale model of NASA's Space Launch System (SLS) is underway. The tests will allow engineers to verify the design of the sound suppression system being developed for the agency's new deep space rocket.
The testing, which began Jan. 16 at NASA's Marshall Space Flight Center in Huntsville, Ala., will focus on how low- and high-frequency sound waves affect the rocket on the launch pad. This testing will provide critical data about how the powerful noise generated by the engines and boosters may affect the rocket and crew, especially during liftoff.
"We can verify the launch environments the SLS vehicle was designed around and determine the effectiveness of the sound suppression systems," said Doug Counter, technical lead for the acoustic testing. "Scale model testing on the space shuttle was very comparable to what actually happened to the vehicle at liftoff. That's why we do the scale test."
During the tests, a 5-percent scale model of the SLS is ignited for five seconds at a time while microphones, located on the vehicle and similarly scaled mobile launcher, tower and exhaust duct, collect acoustic data. A thrust plate, side restraints and cables keep the model secure.
Engineers are running many of the evaluations with a system known as rainbirds, huge water nozzles on the mobile launcher at NASA's Kennedy Space Center in Florida. During launch, 450,000 gallons of water will be released from five rainbirds just seconds before booster ignition. Water is the main component of the sound suppression system because it helps protect the launch vehicle and its payload from damage caused by acoustical energy. SLS with NASA's new Orion spacecraft on top will be launched from Kennedy on deep space missions to destinations such as an asteroid and Mars.
A series of acoustics tests also is taking place at the University of Texas at Austin. Engineers are evaluating the strong sounds and vibrations that occur during the ignition process for the RS-25 engines that will power SLS.

NASA Preparing for 2014 Comet Watch at Mars

This spring, NASA will be paying cautious attention to a comet that could put on a barnstorming show at Mars on Oct. 19, 2014.
On that date, comet C/2013 A1 Siding Spring will buzz Mars about 10 times closer than any identified comet has ever flown past Earth.
Spacecraft at Mars might get a good look at the nucleus of comet Siding Spring as it heads toward the closest approach, roughly 86,000 miles (138,000 kilometers) from the planet, give or take a few percent. On the other hand, dust particles that the comet nucleus sheds this spring could threaten orbiting spacecraft at Mars in October.
The level of risk won’t be known for months, but NASA is already evaluating possible precautionary measures as it prepares for studying the comet.
"Our plans for using spacecraft at Mars to observe comet Siding Spring will be coordinated with plans for how the orbiters will duck and cover, if we need to do that," said Rich Zurek, Mars Exploration Program chief scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif.
Comet Siding Spring, formally named C/2013 A1, was discovered on Jan. 3, 2013, from Australia's Siding Spring Observatory. At the time, it was farther from the sun than Jupiter is. Subsequent observations enabled scientists at JPL and elsewhere to calculate the trajectory the comet will follow as it swings past Mars. Observations in 2014 will continue to refine knowledge of the comet's path, but in approximate terms, Siding Spring's nucleus will come about as close to Mars as one-third of the distance between Earth and the moon.
Comet Ready for Its Close-up
Observations of comet Siding Spring are planned using resources on Earth, orbiting Earth, on Mars and orbiting Mars, and some are already underway.  NASA's Hubble Space Telescope and the NEOWISE mission have observed the comet this month both to characterize this first-time visitor from the Oort cloud and to study dust particle sizes and amounts produced by the comet for understanding potential risks to the Mars orbiters. Infrared imaging by NEOWISE reveals a comet that is active and dusty, even though still nearly three-fourths as far from the sun as Jupiter is. Ground-based observatories such as the NASA Infrared Telescope Facility are also expected to join in as the comet becomes favorably positioned for viewing.
As the comet nears Mars, NASA assets there will be used to study this visitor from distant reaches of the solar system.
"We could learn about the nucleus -- its shape, its rotation, whether some areas on its surface are darker than others," Zurek said.
Researchers using spacecraft at Mars gained experience at trying to observe a different comet in 2013, as comet ISON (formally C/2012 S1) approached Mars. That comet's Mars-flyby distance was about 80 times farther than Siding Spring's will be. Another difference is that ISON continued inward past Mars for nearly two months, briefly becoming visible to some unaided-eye skywatchers on Earth before flying very close to the sun and disintegrating. Siding Spring will reach its closest approach to the sun just six days after its Mars flyby. It won't put on a show for Earth, and it won't return to the inner solar system for about a million years.
At comet Siding Spring's flyby distance, the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter could provide imagery with resolution of dozens of pixels across the diameter of the nucleus. When HiRISE observed comet ISON, the nucleus was less than one pixel across. ISON did not get bright enough to make itself visible to other cameras at Mars that made attempted observations, but Siding Spring could provide a better observation opportunity.
Cameras on the Mars rovers Curiosity and Opportunity might watch for meteors in the sky that would be an indication of the abundance of particles in the comet's tail, though the geometry of the flyby would put most of the meteors in daytime sky instead of dark sky.
"A third aspect for investigation could be what effect the infalling particles have on the upper atmosphere of Mars," Zurek said. "They might heat it and expand it, not unlike the effect of a global dust storm." Infrared-sensing instruments on Mars Reconnaissance Orbiter and Odyssey might be used to watch for that effect.
Assessing Possible Hazards to Mars Orbiters
One trait Siding Spring shares with ISON is unpredictability about how much it will brighten in the months before passing Mars. The degree to which Siding Spring brightens this spring will be an indicator of how much hazard it will present to spacecraft at Mars.
"It's way too early for us to know how much of a threat Siding Spring will be to our orbiters," JPL's Soren Madsen, Mars Exploration Program chief engineer, said last week. "It could go either way. It could be a huge deal or it could be nothing -- or anything in between."
The path the nucleus will take is now known fairly well. The important unknowns are how much dust will come off the nucleus, when it will come off, and the geometry of the resulting coma and tail of the comet.
During April and May, the comet will cross the range of distances from the sun at which water ice on a comet's surface typically becomes active -- vaporizing and letting dust particles loose. Dust ejected then could get far enough from the nucleus by October to swarm around Mars.
"How active will Siding Spring be in April and May? We'll be watching that," Madsen said. "But if the red alarm starts sounding in May, it would be too late to start planning how to respond. That's why we're doing what we're doing right now."
Two key strategies to lessen risk are to get orbiters behind Mars during the minutes of highest risk and to orient orbiters so that the most vulnerable parts are not in the line of fire.
The Martian atmosphere, thin as it is, is dense enough to prevent dust from the comet from becoming a hazard to NASA's two Mars rovers active on the surface. Three orbiters are currently active at Mars:  NASA's Mars Reconnaissance Orbiter (MRO) and Mars Odyssey, and the European Space Agency's Mars Express. Two more departed Earth in late 2013 and are due to enter orbit around Mars about three weeks before the comet Siding Spring flyby: NASA's Mars Atmosphere and Volatile Evolution (MAVEN) and India's Mars Orbiter Mission.
Orbiters are designed with the risk of space-dust collisions in mind. Most such collisions do not damage a mission. Design factors such as blanketing and protected placement of vulnerable components help. Over a five-year span for a Mars orbiter, NASA figures on a few percent chance of significant damage to a spacecraft from the background level of impacts from such particles, called meteoroids. Whether the Siding Spring level will pack that much hazard -- or perhaps greater than 10 times more -- into a few hours will depend on how active it becomes.
This comet is orbiting the sun in almost the opposite direction as Mars and the other planets. The nucleus and the dust particles it sheds will be travelling at about 35 miles (56 kilometers) per second, relative to the Mars orbiters. That's about 50 times faster than a bullet from a high-powered rifle and double or triple the velocity of background meteoroid impacts.
Cautionary Preparations
If managers choose to position orbiters behind Mars during the peak risk, the further in advance any orbit-adjustment maneuvers can be made, the less fuel will be consumed. Advance work is also crucial for the other main option: reorienting a spacecraft to keep its least-vulnerable side facing the oncoming stream of comet particles. The safest orientation in terms of comet dust may be a poor one for maintaining power or communications.
"These changes would require a huge amount of testing," Madsen said. "There's a lot of preparation we need to do now, to prepare ourselves in case we learn in May that the flyby will be hazardous."

New NASA Laser Technology Reveals How Ice Measures Up

New results from NASA's MABEL campaign demonstrated that a photon-counting technique will allow researchers to track the melt or growth of Earth’s frozen regions.
When a high-altitude aircraft flew over the icy Arctic Ocean and the snow-covered terrain of Greenland in April 2012, it was the first polar test of a new laser-based technology to measure the height of Earth from space.
Aboard that aircraft flew the Multiple Altimeter Beam Experimental Lidar, or MABEL, which is an airborne test bed instrument for NASA's ICESat-2 satellite mission slated to launch in 2017. Both MABEL and ICESat-2's ATLAS instrument are photon counters – they send out pulses of green laser light and time how long it takes individual light photons to bounce off Earth's surface and return. That time, along with ATLAS’ exact position from an onboard GPS, will be plugged into computer programs to tell researchers the elevation of Earth's surface – measuring change to as little as the width of a pencil.
This kind of photon-counting technology is novel for satellites; from 2003 to 2009, ICESat-1’s instrument looked at the intensity of a returned laser signal, which included many photons. So getting individual photon data from MABEL helps scientists prepare for the vast amounts of elevation data they'll get from ICESat-2.
"Using the individual photons to measure surface elevation is a really new thing," said Ron Kwok, a senior research scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "It's never been done from orbiting satellites, and it hasn't really been done much with airborne instruments, either."
ICESat-2 is tasked with measuring elevation across Earth's entire surface, including vegetation and oceans, but with a focus on change in the frozen areas of the planet, where scientists have observed dramatic impacts from climate change. There, two types of ice – ice sheets and sea ice – reflect light photons in different patterns. Ice sheets and glaciers are found on land, like Greenland and Antarctica, and are formed as frozen snow and rain accumulates. Sea ice, on the other hand, is frozen seawater, found floating in the Arctic Ocean and offshore of Antarctica.
MABEL's 2012 Greenland campaign was designed to observe a range of interesting icy features, said Bill Cook, MABEL's lead scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. With the photon counts from different surfaces, other scientists could start analyzing the data to determine which methods of analyzing the data allow them to best measure the elevation of Earth's surface.
"We wanted to get a wide variety of target types, so that the science team would have a lot of data to develop algorithms," Cook said. "This was our first real dedicated science mission."
The flights over the ocean near Greenland, for example, allowed researchers to demonstrate that they can measure the height difference between open water and sea ice, which is key to determining the ice thickness. MABEL can detect enough of the laser light photons that bounce off Earth surface and return to the instrument, and programs can then make necessary elevation calculations, Cook said.
 Part of what we're doing with MABEL is to demonstrate ICESat-2's instrument is going to have the right sensitivity to do the measurements," Cook said. "You can do this photon counting if you have enough photons."
In an article recently published in the Journal of Atmospheric and Oceanic Technology, Kwok and his colleagues showed how to calculate elevation from MABEL data, and do so over different types of ice – from open water, to thin, glassy ice, to the snow-covered ice.
"We were pretty happy with the precision," Kwok said. "The flat areas are flat to centimeter level, and the rough areas are rough." And the density of photons detection could also tell researchers what type of ice the instrument was flying over.
The contours of the icy surface are also important when monitoring ice sheets and glaciers covering land. The original ICESat-1 mission employed a single laser, which made it more difficult to measure whether the ice sheet had gained or lost elevation. With a single beam, when the instrument flew over a spot a second time, researchers couldn't tell if the snowpack had melted or if the laser was slightly off and pointed down a hill. Because of this, scientists needed 10 passes over an area to determine whether the ice sheet was changing, said Kelly Brunt, a research scientist at NASA Goddard.
"ICESat-1 was fantastic, but it was a single beam instrument," Brunt said. "We're more interested in repeating tracks to monitor change – that's hard to do."
ICESat-2 addresses this problem by splitting the laser into six beams. These are arranged in three pairs, and the beams within a pair are spaced 295 feet (90 meters), or just less than a football field apart. By comparing the height of one site to the height of its neighbor, scientists can determine the terrain's general slope.
Brunt and her colleagues used MABEL data from the 2012 Greenland campaign to try to detect slopes as shallow as 4 percent incline; their results will be published in the May 2014 issue of the journal Geoscience and Remote Sensing Letters. They counted only a portion of the photons, in order to simulate the weaker laser beams that ICESat-2 will carry. With computer programs to determine the slope, the researchers verified it against results from earlier missions.
"The precision is great," Brunt said. "We're very confident that with ICESat-2's beam pair, we can see slope."
And there are still more things for MABEL to measure. The instrument team is planning a 2014 summer campaign to fly over glaciers and ice sheets in warmer weather. "We want to see what the effects of the melt is," Cook said. "How do glaciers look if they're warmer, rather than colder?"