Jul 1 2015
From The Space Library
Release 15-143 NASA’s New Horizons Spacecraft Stays the Course to Pluto
NASA’s New Horizons spacecraft is getting a final “all clear” as it speeds closer to its historic July 14 flyby of Pluto and the dwarf planet’s five moons.
After seven weeks of detailed searches for dust clouds, rings, and other potential hazards, the New Horizons team has decided the spacecraft will remain on its original path through the Pluto system instead of making a late course correction to detour around any hazards. Because New Horizons is traveling at 30,800 mph (49,600 kph), a particle as small as a grain of rice could be lethal.
“We’re breathing a collective sigh of relief knowing that the way appears to be clear,” said Jim Green, director of planetary science at NASA. “The science payoff will be richer as we gather data from the optimal flight path, as opposed to having to conduct observations from one of the back-up trajectories.”
Mission scientists have been using the spacecraft’s most powerful telescopic camera, the Long Range Reconnaissance Imager (LORRI), to look for potential hazards, such as small moons, rings, or dust, since mid-May. The decision on whether to keep the spacecraft on its original course or adopt a Safe Haven by Other Trajectory, or "SHBOT" path, had to be made this week since the last opportunity to maneuver New Horizons onto an alternate trajectory is July 4.
“Not finding new moons or rings present is a bit of a scientific surprise to most of us,” said principal investigator Alan Stern of the Southwest Research Institute (SwRI) in Boulder, Colorado. “But as a result, no engine burn is needed to steer clear of potential hazards. We presented these data to NASA for review and received approval to proceed on course and plan. We are ‘go’ for the best of our planned Pluto encounter trajectories.”
New Horizons formed a hazard analysis team in 2011, after the discovery of Pluto’s fourth moon, Kerberos, raised concerns the cratering of these moons by small debris from the outer area of the solar system known as the Kuiper Belt, could spread additional hazardous debris into New Horizons’ path. Mission engineers re-tested spare spacecraft blanketing and parts back on Earth to determine how well they would stand up to particle impacts, and scientists modeled the likely formation and locations of rings and debris in the Pluto system. By the time New Horizons’ cameras were close enough to Pluto to start the search last month, the team had already estimated the chances of a catastrophic incident at far less than one percent.
The images used in the latest searches that cleared the mission to stay on its current course were taken June 22, 23 and 26. Pluto and all five of its known moons are visible in the images, but scientists saw no rings, new moons, or hazards of any kind. The hazards team determined that satellites as faint as about 15 times dimmer than Pluto’s faintest known moon, Styx, would have been seen if they existed beyond the orbit of Pluto’s largest and closest moon, Charon.
If any rings do exist, the hazard team determined they must be extremely faint, reflecting less than one 5-millionth of the incoming sunlight.
“The suspense – at least most of it – is behind us,” says John Spencer, of SwRI, who leads the New Horizons hazard analysis team. “As a scientist I’m a bit disappointed that we didn’t spot additional moons to study, but as a New Horizons team member I am much more relieved that we didn’t find something that could harm the spacecraft. New Horizons already has six amazing objects to analyze in this incredible system.”
The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft, and manages the mission for NASA’s Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama.
Release C15-021 NASA Awards Earth Science Data and Information Contract
NASA has awarded the Earth Observing System Data and Information System (EOSDIS) Evolution and Development (EED)-2 contract to Raytheon Company of Riverdale, Maryland.
The total value of this cost-plus-award-fee, indefinite-delivery/indefinite-quantity task order contract is $240 million. The contract has a five-year ordering period beginning Sept. 1. Individual efforts may extend beyond five years.
The EOSDIS ingests, archives, processes and distributes large volumes of science data to millions of science users per year. The scope of this contract is to design, develop, evolve and sustain the state-of-the-art science system for NASA’s Earth Science data. The principal work will be performed at NASA’s Goddard Space Flight Center, Greenbelt, Maryland, and at the contractor’s facility nearby.
Release 15-142 NASA Takes to Kansas Skies to Study Nighttime Thunderstorms
NASA has joined a multi-agency field campaign studying summer storm systems in the U.S. Great Plains to find out why they often form after the sun goes down instead of during the heat of the day.
The Plains Elevated Convection at Night, or PECAN, project began June 1 and continues through mid-July. Participants from eight research laboratories and 14 universities are collecting storm data to find out how and why they form. NASA’s DC-8 airborne laboratory began research flights Tuesday from the Salina Regional Airport, Salina, Kansas.
“We’re hoping to collect measurements that will be used to characterize the atmosphere ahead of these storms,” said Richard Ferrare, senior research scientist in the Atmospheric Sciences Division at NASA’s Langley Research Center, Hampton, Virginia. “If we can map the water vapor that goes into these storms, we’ll be able to improve computer models that represent these conditions and better predict the storms.”
The NASA DC-8 and National Oceanic and Atmospheric Administration (NOAA) P-3 Orion research aircraft supporting the PECAN mission will be open to the media from 3 to 5 p.m. CDT on Saturday, July 11, at the Salina Regional Airport. The airport is located at 3237 Arnold Avenue.
Unlike other parts of the United States, summer thunderstorms across the Great Plains are most common after sunset. Much of the rain comes from medium-size weather systems and resulting thunderstorms known as mesoscale convective systems. These nighttime storms can produce heavy rainfall that contributes a significant portion of the yearly precipitation in the region.
Scientists understand that thunderstorms that form during the day result from a vertical “convective” circulation driven by rising warm air from the heated Earth’s surface and falling air cooled at higher altitudes in the atmosphere. Less well understood are the mechanisms that cause thunderstorms after the sun has gone down and the land surface has cooled.
The DC-8 carries atmospheric science instruments and investigators from Langley; NASA’s Jet Propulsion Laboratory, Pasadena, California; and several universities and research labs. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is providing a ground-based Doppler radar system.
PECAN is funded by the National Science Foundation with additional support from NASA, the National Oceanic and Atmospheric Administration (NOAA), the National Center for Atmospheric Research in Boulder, Colorado, and the Department of Energy.
In addition to the NASA and NOAA aircraft, researchers will receive data from a University of Wyoming King Air plane, ground-based instruments, weather balloons and mobile radars. Storm information will continue to be gathered from multiple agency ground and air instruments across northern Oklahoma, central Kansas, and south-central Nebraska through July.
The DC-8 is based at NASA’s Armstrong Flight Research Facility in Palmdale, California, and supports NASA’s Airborne Science Program under the Science Mission Directorate. The extended range, prolonged flight-duration capability, large payload capacity, and laboratory environment of the DC-8 make it one of the premier aircraft available for NASA Earth science investigations.
NASA researchers collect and study data from space, air, land and sea to tackle challenges facing the world today, including improved environmental prediction and natural hazard and climate change preparedness. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing.
