Satellite News

Ten years ago, on Dec. 30, 2000, NASA's Cassini spacecraft made its closest approach to Jupiter on its way to orbiting Saturn. The main purpose was to use the gravity of the largest planet in our solar system to slingshot Cassini towards Saturn, its ultimate destination. But the encounter with Jupiter, Saturn's gas-giant big brother, also gave the Cassini project a perfect lab for testing its instruments and evaluating its operations plans for its tour of the ringed planet, which began in 2004.

"The Jupiter flyby allowed the Cassini spacecraft to stretch its wings, rehearsing for its prime time show, orbiting Saturn," said Linda Spilker, Cassini project scientist based at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Ten years later, findings from the Jupiter flyby still continue to shape our understanding of similar processes in the Saturn system."

Cassini spent about six months - from October 2000 to March 2001 - exploring the Jupiter system. The closest approach brought Cassini to within about 9.7 million kilometers (6 million miles) of Jupiter's cloud tops at 2:05 a.m. Pacific Time, or 10:05 a.m. UTC, on Dec. 30, 2000.

Cassini captured some 26,000 images of Jupiter and its moons over six months of continual viewing, creating the most detailed global portrait of Jupiter yet.

While Cassini's images of Jupiter did not have higher resolution than the best from NASA's Voyager mission during its two 1979 flybys, Cassini's cameras had a wider color spectrum than those aboard Voyager, capturing wavelengths of radiation that could probe different heights in Jupiter's atmosphere. The images enabled scientists to watch convective lightning storms evolve over time and helped them understand the heights and composition of these storms and the many clouds, hazes and other types of storms that blanket Jupiter.

Technicians in the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida are making such good progress with X-ray type image scans of space shuttle Discovery's external fuel tank that they expect to finish the job today, a day ahead of schedule.

The team has been using a refined method of gathering the computed radiography scans of all 108 support beams, called stringers, on the outside of the external tank’s intertank section. The method has provided overlapping images, which has lowered the need to have scans retaken.

Engineers at other NASA locations are analyzing the new image scans, which began Sunday. The new data, along with previous testing and analysis, will help engineers and managers determine what caused small cracks on the tops of two stringers during Discovery’s launch countdown on Nov. 5.

Space Shuttle Program managers still are scheduled to decide Thursday afternoon whether testing and analysis indicate modifications are needed on some of the stringers. If required, modifications would begin next Monday

One of the greatest challenges that NASA faces in incorporating advanced technologies into future missions is bridging the mid-Technology Readiness Level (TRL 3-6) gap between early conceptual studies and infusion of a new technology onto the critical path of a science or exploration mission. Maturing a space technology to flight readiness status through relevant environment testing is a significant challenge from both a cost and risk perspective. Flight demonstration of a technology is often considered too risky or too costly for a mission. The Crosscutting Capability Demonstrations Division matures a small number of technologies that are of benefit to multiple customers to flight readiness status, TRL 6 or higher.

The Crosscutting Capability Demonstrations Division consists of three programs that will demonstrate technologies in a relevant environment:

Snows are finally winding down in New England today, Dec. 27, as a powerful low pressure system brought blizzard conditions from northern New Jersey to Maine over Christmas weekend. The GOES-13 satellite captured an image of the low's center off the Massachusetts coast and saw the snowfall left behind.

The Geostationary Operational Environmental Satellite called GOES-13 captured the visible image. GOES satellites are operated by the National Oceanic and Atmospheric Administration, and NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md. creates some of the GOES satellite images and animations.

As of 1:30 p.m. EST, all blizzard warnings were canceled as the low has pulled much of its snow and rain away from land areas and into the North Atlantic Ocean. The winds behind the system are now causing more problems for residents along the U.S. East coast.

Snowfall ranged from 1.5 inches in Atlanta, Georgia to more than a foot in various areas of New Jersey, New York and the New England states. Near Wallops Island, Va. where NASA has a facility, more than 11 inches of snow was reported this morning. Newark, N.J. reported 17.7 inches of snow by midnight last night. Central Park in New York City reported 12.0 inches of snow had fallen just before midnight. Providence, Rhode Island reported 7.9 inches by midnight, while Boston, Mass. reported 9.9 inches at that time. More snow fell on top of those totals during the morning hours today.

Some of those snows are visible in today's GOES-13 satellite image. Snowfall on the ground can be seen in the image over South and North Carolina, Virginia, Maryland, Delaware, eastern Pennsylvania, New Jersey, and southeastern New York. The clouds of the low obscure New England in the image.

From Maine south to the Carolinas winds are howling in excess of 30 mph, and power outages could occur as a result of the winds and the areas with the heaviest snows. The winds in Portland, Maine today are blowing from the northwest from 20 to 30 mph with gusts over 40 mph. Yesterday in Newark, N.J. sustained winds of 41 mph were reported with gusts as high as 51 mph. Going further south, the Raleigh, N.C. National Weather Service noted that sustained northwest winds of 10 to 20 mph with gusts up to 30 mph are expected today. Even further south, Atlanta, Georgia is also experiencing winds up to 20 mph today.

The winds are making clean-up efforts difficult along the east coast, but as temperatures are expected to slowly and steadily climb over the course of the week travel will become easier every day.

A rock-zapping laser instrument on NASA's next Mars rover has roots in a demonstration that Roger Wiens saw 13 years ago in a colleague's room at Los Alamos National Laboratory in New Mexico.

The Chemistry and Camera (ChemCam) instrument on the rover Curiosity can hit rocks with a laser powerful enough to excite a pinhead-size spot into a glowing, ionized gas. ChemCam then observes the flash through a telescope and analyzes the spectrum of light to identify the chemical elements in the target.

That information about rocks or patches of soil up to about 7 meters (23 feet) away will help the rover team survey the rover's surroundings and choose which targets to drill into, or scoop up, for additional analysis by other instruments on Curiosity. With the 10 science instruments on the rover, the team will assess whether any environments in the landing area have been favorable for microbial life and for preserving evidence about whether life existed. In late 2011, NASA will launch Curiosity and the other parts of the flight system, delivering the rover to the surface of Mars in August 2012.

Wiens, a geochemist with the U.S. Department of Energy's Los Alamos National Laboratory, serves as ChemCam's principal investigator. An American and French team that he leads proposed the instrument during NASA's 2004 open competition for participation in the Mars Science Laboratory project, whose rover has since been named Curiosity.

In 1997, while working on an idea for using lasers to investigate the moon, Wiens visited a chemistry laboratory building where a colleague, Dave Cremers, had been experimenting with a different laser technique. Cremers set up a cigar-size laser powered by a little 9-volt radio battery and pointed at a rock across the room.

On Dec. 16, 2010, NASA's Mars Exploration Rover Opportunity reached a crater about the size of a football field—some 90 meters (295 feet) in diameter. The rover team plans to use cameras and spectrometers during the next several weeks to examine rocks exposed at the crater, informally named "Santa Maria."

A mosaic of image frames taken by Opportunity's navigation camera on Dec. 16 shows the crater's sharp rim and rocks ejected from the impact that had excavated the crater.

Opportunity completed its three-month prime mission on Mars in April 2004 and has been working in bonus extended missions since then. After the investigations at Santa Maria, the rover team plans to resume a long-term trek by Opportunity to the rim of Endeavour Crater, which is about 22 kilometers (14 miles) in diameter.

NASA has taken the next step toward a new generation of Deep Space Network antennas. A $40.7 million contract with General Dynamics SATCOM Technologies, San Jose, Calif., covers implementation of two additional 34-meter (112-foot) antennas at Canberra, Australia. This is part of Phase I of a plan to eventually retire the network's aging 70-meter-wide (230-foot-wide) antennas.

The Deep Space Network (DSN) consists of three communications complexes: in Goldstone, California Madrid, Spain; and Canberra, Australia. The 70-meter antennas are more than 40 years old and are showing signs of surface deterioration from constant use. Additional 34-meter antennas are being installed in Canberra in the first phase; subsequent phases will install additional 34-meter antennas in Goldstone and Madrid.

The 34-meter beam waveguide antennas are essential to keep communications flowing smoothly as NASA's fleet of spacecraft continues to expand. In addition, the waveguide design of the antennas provides easier access for maintenance and future upgrades, because sensitive electronics are housed in a below-the-ground pedestal equipment room, instead of in the center of the dish.Read More

NASA and Pratt & Whitney Rocketdyne have successfully completed the heart of the J-2X upper stage rocket engine - the turbomachinery assemblies - for the first development engine off the production line.

The engine's turbomachinery consists of two turbopumps, each part pump and part turbine. Turbines provide the power to drive the pumps. One pump pushes high-pressure liquid oxygen, or oxidizer, and the other pumps liquid hydrogen fuel through the engine and to the engine's main injector. When the two meet, the fuels combine in a controlled high-pressure explosion producing the combustion needed to propel a launch vehicle to its journey to space.

"The turbopumps are extremely complicated engine components whose design requires delicate balances between many of the fields of mechanical engineering, and whose fabrication and assembly involve extremely precise construction," said Gary Genge, J-2X turbomachinery manager at NASA's Marshall Space Flight Center in Huntsville, Ala. "We're thrilled these parts are completed, and are ready to send to Stennis Space Center for assembly onto our first engine."

The J-2X engine is a highly efficient and versatile rocket engine and has the ideal thrust and performance characteristics to power the upper stage of a heavy-lift launch vehicle. Investments made in developing the J-2X engine provide the nation with a new, robust rocket engine for future human spaceflight missions to low-Earth orbit, Mars or an asteroid. Read More

Christmas Eve, 1968. As one of the most turbulent, tragic years in American history drew to a close, millions around the world were watching and listening as the Apollo 8 astronauts -- Frank Borman, Jim Lovell and Bill Anders -- became the first humans to orbit another world.

As their command module floated above the lunar surface, the astronauts beamed back images of the moon and Earth and took turns reading from the book of Genesis, closing with a wish for everyone "on the good Earth."

"We were told that on Christmas Eve we would have the largest audience that had ever listened to a human voice," recalled Borman during 40th anniversary celebrations in 2008. "And the only instructions that we got from NASA was to do something appropriate."

"The first ten verses of Genesis is the foundation of many of the world's religions, not just the Christian religion," added Lovell. "There are more people in other religions than the Christian religion around the world, and so this would be appropriate to that and so that's how it came to pass."

The mission was also famous for the iconic "Earthrise" image, snapped by Anders, which would give humankind a new perspective on their home planet. Anders has said that despite all the training and preparation for an exploration of the moon, the astronauts ended up discovering Earth.

The Apollo 8 astronauts got where they were that Christmas Eve because of a bold, improvisational call by NASA. With the clock ticking on President Kennedy's challenge to land on the moon by decade's end, delays with the lunar module were threatening to slow the Apollo program. So NASA decided to change mission plans and send the Apollo 8 crew all the way to the moon without a lunar module on the first manned flight of the massive Saturn V rocket.

The crew rocketed into orbit on December 21, and after circling the moon 10 times on Christmas Eve, it was time to come home. On Christmas morning, mission control waited anxiously for word that Apollo 8's engine burn to leave lunar orbit had worked. They soon got confirmation when Lovell radioed, "Roger, please be informed there is a Santa Claus."

The crew splashed down in the Pacific on December 27. A lunar landing was still months away, but for the first time ever, men from Earth had visited the moon and returned home safely.

Thanks for this article: http://www.nasa.gov/topics/history/features/apollo_8.html

Lots of questions are coming in about the best times to view this around the world. Here's a summary from our astronomers below:

"Early in the morning on Dec. 21, a total lunar eclipse will be visible to sky watchers around the world. The eclipse is visible across all of North America - for viewers in western states, the eclipse actually begins late in the evening of Dec. 20. Viewers in Greenland, Iceland and western Europe will be able to see the beginning stages of the eclipse before moonset. In western Asia, the later stages of the eclipse will be visible after moonrise. 

All of the eclipse will be visible throughout Mexico and Central America and northwest South America. Viewers in Peru, Chile and Bolivia will see most of the eclipse, but the moon will set before the end of the Penumbral phase. Viewers in Brazil will see the moon set during totality. Parts of Africa in the northwest will also see the moon set while it is eclipsed. All but the westernmost tip of Australia will see an eclipsed moon as it rises. Unfortunately most of Africa, the middle East and India will not have a view of this event. This map will help you determine the viewing in your area." Read More

Two satellite instruments aboard NASA's Solar Radiation & Climate Experiment (SORCE) mission - the Total Solar Irradiance Monitor (TIM) and the Solar Irradiance Monitor (SIM) - have made daily measurements of the sun's brightness since 2003.

The two instruments are part of an ongoing effort to monitor variations in solar output that could affect Earth's climate. Both instruments measure aspects of the sun's irradiance, the intensity of the radiation striking the top of the atmosphere.

Instruments similar to TIM have made daily irradiance measurements of the entire solar spectrum for more than three decades, but the SIM instrument is the first to monitor the daily activity of certain parts of the spectrum, a measurement scientists call solar spectral irradiance.

In recent years, SIM has collected data that suggest the sun's brightness may vary in entirely unexpected ways. If the SIM's spectral irradiance measurements are validated and proven accurate over time, then certain parts of Earth’s atmosphere may receive surprisingly large doses of solar radiation even during lulls in solar activity.

"We have never had a reason until now to believe that parts of the spectrum may vary out of phase with the solar cycle, but now we have started to model that possibility because of the SIM results,” said Robert Cahalan, the project scientist for SORCE and the head of the climate and radiation branch at NASA's Goddard Space Flight Center in Greenbelt, Md.

Cahalan, as well as groups of scientists from the University of Colorado at Boulder and Johns Hopkins University, presented research at the American Geophysical Union meeting in San Francisco in December that explored the climate implications of the recent SIM measurements.

Cahalan’s modeling, for example, suggests that the sun may underlie variations in stratospheric temperature more strongly than currently thought. Measurements have shown that stratospheric temperatures vary by about 1 °C (1.8 °F) over the course of a solar cycle, and Cahalan has demonstrated that inputting SIM’s measurements of spectral irradiance into a climate model produces variations of that same magnitude.

Without inclusion of SIM data, the model produces stratospheric temperature variations only about a fifth as strong as would be needed to explain observed stratospheric temperature variations. "We may have a lot more to learn about how solar variability works, and how the sun might influence our climate," Cahalan said. Read More...

At NASA's Kennedy Space Center in Florida, technicians are finalizing preparations at Launch Pad 39A for a tanking test on space shuttle Discovery's external fuel tank on Friday, Dec. 17.

The rotating service structure will be moved away from the spacecraft tonight at 9:30 p.m. EST. Managers will meet at 6:30 a.m. Friday for a weather briefing before beginning the test at 7 a.m.

The test will help verify repairs associated with cracks on the tops of two 21-foot-long, U-shaped aluminum brackets, called stringers, on the external tank.

Data collected from the strain gauge and thermal couple sensors will potentially help engineers determine what caused the cracks during Discovery's launch countdown on Nov. 5. Technicians repaired the cracks and reapplied foam insulation on the stringers last month.

Results of the instrumented test will not be known immediately. Managers and engineers will review the data gathered from the test before determining the next course of action. Discovery’s next launch opportunity is no earlier than 1:34 a.m. on Feb. 3.