A United Launch Alliance Delta II rocket with the Soil Moisture Active Passive(SMAP) observatory onboard is seen in this long exposure photograph as it launches from Space Launch Complex 2, Saturday, Jan. 31, 2015, Vandenberg Air Force Base, Calif. SMAP is NASA’s first Earth-observing satellite designed to collect global observations of surface soil moisture and its freeze/thaw state. SMAP will provide high resolution global measurements of soil moisture from space. The data will be used to enhance scientists' understanding of the processes that link Earth's water, energy, and carbon cycles.
Astronomers Discover Ancient System with Five Small Planets (Press Release)
Astronomers using data from NASA's Kepler mission have discovered a planetary system of five small planets dating back to when the Milky Way galaxy was a youthful two billion years old.
The tightly packed system, named Kepler-444, is home to five planets that range in size, the smallest comparable to the size of Mercury and the largest to Venus. All five planets orbit their sun-like star in less than ten days, which makes their orbits much closer than Mercury's sweltering 88-day orbit around the sun.
"While this star formed a long time ago, in fact before most of the stars in the Milky Way, we have no indication that any of these planets have now or ever had life on them," said Steve Howell, Kepler/K2 project scientist at NASA's Ames Research Center in Moffett Field, California. "At their current orbital distances, life as we know it could not exist on these ancient worlds."
Kepler-444 formed 11.2 billion years ago, when the universe was less than 20 percent its current age. This makes Kepler-444 the oldest known system of terrestrial-size planets, two and a half times older than the Earth.
To determine the age of the star and thus its planets, scientists measured the very small change in brightness of the host star caused by pressure waves within the star. The boiling motion beneath the surface of the star generates these pressure waves, affecting the star's temperature and luminosity. These fluctuations lead to miniscule changes or variations in a star's brightness. This study of the interior of stars is called asteroseismology and allows the researchers to measure the diameter, mass and age of a star.
The Kepler-444 system is approximately 117 light-years away toward the constellation Lyra. A paper reporting this discovery is published in The Astrophysical Journal.
Ames is responsible for Kepler's mission operations, ground system development and science data analysis. NASA's Jet Propulsion Laboratory in Pasadena, California, managed Kepler mission development. Ball Aerospace & Technologies Corp. in Boulder, Colorado, developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder. The NASA Exoplanet Archive in Pasadena and the Space Telescope Science Institute in Baltimore archive, host and distribute Kepler science data. Kepler is NASA's 10th Discovery Mission and was funded by the agency's Science Mission Directorate in Washington.
Rosetta Watches Comet Shed Its Dusty Coat (Press Release - January 26)
ESA’s Rosetta mission is providing unique insight into the life cycle of a comet’s dusty surface, watching 67P/Churyumov–Gerasimenko as it sheds the dusty coat it has accumulated over the past four years.
The COmetary Secondary Ion Mass Analyser, or COSIMA, is one of Rosetta’s three dust analysis experiments. It started collecting, imaging and measuring the composition of dust particles shortly after the spacecraft arrived at the comet in August 2014.
Results from the first analysis of its data are reported today in the journal Nature. The study covers August to October, when the comet moved along its orbit between about 535 million kilometres to 450 million kilometres from the Sun. Rosetta spent the most of this time orbiting the comet at distances of 30 km or less.
The scientists looked at the way that many large dust grains broke apart when they were collected on the instrument’s target plate, typically at low speeds of 1–10 m/s. The grains, which were originally at least 0.05 mm across, fragmented or shattered upon collection.
The fact that they broke apart so easily means that the individual parts were not well bound together. Moreover, if they had contained ice, they would not have shattered. Instead, the icy component would have evaporated off the grain shortly after touching the collecting plate, leaving voids in what remained.
By comparison, if a pure water-ice grain had struck the detector, then only a dark patch would have been seen.
The dust particles were found to be rich in sodium, sharing the characteristics of ‘interplanetary dust particles’. These are found in meteor streams originating from comets, including the annual Perseids from Comet 109P/Swift–Tuttle and the Leonids from 55P/Tempel–Tuttle.
“We found that the dust particles released first when the comet started to become active again are ‘fluffy’. They don’t contain ice, but they do contain a lot of sodium. We have found the parent material of interplanetary dust particles,” says lead author Rita Schulz of ESA’s Scientific Support Office.
The scientists believe that the grains detected were stranded on the comet’s surface after its last perihelion passage, when the flow of gas away from the surface had subsided and was no longer sufficient to lift dust grains from the surface.
While the dust was confined to the surface, the gas continued evaporating at a very low level, coming from ever deeper below the surface during the years that the comet travelled furthest from the Sun. Effectively, the comet nucleus was ‘drying out’ on the surface and just below it.
“We believe that these ‘fluffy’ grains collected by Rosetta originated from the dusty layer built up on the comet’s surface since its last close approach to the Sun,” explains Martin Hilchenbach, COSIMA principal investigator at the Max-Planck Institute for Solar System research in Germany.
“This layer is being removed as the activity of the comet is increasing again. We see this layer being removed, and we expect it to evolve into a more ice-rich phase in the coming months.”
The comet is on a 6.5-year circuit around the Sun, and is moving towards its closest approach in August of this year. At that point, Rosetta and the comet will be 186 million kilometres from the Sun, between the orbits of Earth and Mars.
As the comet warms, the outflow of gases is increasing and the grains making up the dry surface layers are being lifted into the inner atmosphere, or coma. Eventually, the incoming solar energy will be high enough to remove all of this old dust, leaving fresher material exposed at the surface.
“In fact, much of the comet’s dust mantle should actually be lost by now, and we will soon be looking at grains with very different properties,” says Rita.
“Rosetta’s dust observations close to the comet nucleus are crucial in helping us to link together what is happening at the very small scale with what we see at much larger scales, as dust is lost into the comet’s coma and tail,” says Matt Taylor, ESA’s Rosetta project scientist.
“For these observations, it really is a case of “watch this space” as we continue to watch in real time how the comet evolves as it approaches the Sun along its orbit over the coming months.”
Planetary Society Announces Test Flight for Privately Funded LightSail Spacecraft (Press Release)
CEO Bill Nye, Neil deGrasse Tyson, partners invite public to follow May 2015 mission
Pasadena, CA (January 26, 2015) – The Planetary Society today announced the first of its LightSail spacecraft will embark on a May 2015 test flight. Funded entirely by private citizens, the solar sail satellite will hitch a ride to space aboard an Atlas V rocket from Cape Canaveral Air Force Station in Florida. The mission will test LightSail’s critical functions, a precursor to a second mission slated for 2016. That second flight will mark the first controlled, Earth-orbit solar sail flight and ride along with the first operational launch of SpaceX's Falcon Heavy rocket.
“There's an old saying in aerospace, 'One test is worth a thousand expert opinions.’ After six years of development, we're ready at last to see how LightSail flies," said Bill Nye (The Science Guy), CEO at The Planetary Society.
"LightSail is technically wonderful, but it's also wonderfully romantic. We'll sail on sunbeams,” added Nye. “But wait, there’s more: this unique, remarkable spacecraft is funded entirely by private citizens, people who think spaceflight is cool."
Solar sailing works by using sunlight for propulsion. When solar photons strike LightSail's reflective Mylar® sails, their momentum is transferred to the spacecraft, gradually accelerating it through space. While the push from photons is miniscule, it is continuous and unlimited. Solar sails can eventually reach greater speeds than those obtained from chemical rockets. LightSail consists of four identical triangular sails attached to four 4-meter booms, resulting in a square solar sail when fully deployed.
The 2015 test flight will not carry the spacecraft high enough to escape Earth's atmospheric drag, and will thus not demonstrate controlled solar sailing. Once in orbit, the spacecraft will go through a checkout and testing period of about four weeks before deploying its solar sails. After the sails unfurl, LightSail will test its attitude control system and study the behavior of the sails for a few days before it is pulled back into the planet's atmosphere. Key images and data on the spacecraft's performance will be sent to ground stations at Cal Poly San Luis Obispo and Georgia Tech.
Dr. Neil deGrasse Tyson, Hayden Planetarium director and Planetary Society board of directors member, added, “With the expected launch of LightSail -- a craft propelled among the stars on the pressure of light itself -- the expanse of space becomes a literal analogue to the open seas. If space is tomorrow's ocean, then Earth’s surface is its shoreline.”
LightSail is packaged into a small spacecraft called a CubeSat. CubeSats have made low-cost space missions a reality for universities and research groups. However, providing propulsion for these tiny satellites has been a major challenge. LightSail will demonstrate the viability of solar sailing for CubeSats. The spacecraft was designed by Stellar Exploration, Inc., in San Luis Obispo, Calif. LightSail's lead contractor for integration and testing is Pasadena, Calif.-based Ecliptic Enterprises Corporation, a space avionics and sensor systems firm best known for its popular RocketCam™ family of video systems used on rockets and spacecraft.
“Starting with a clever ‘3U’ CubeSat design from Stellar Exploration, a small team at Ecliptic was tasked a year ago with completing the final integration and testing of this first LightSail spacecraft,” said Rex Ridenoure, CEO of Ecliptic. “We experienced several design, hardware, software and testing issues along the way, but thanks to excellent technical support from Stellar Exploration, Boreal Space, Half Band Technologies, Cal Poly, Georgia Tech and others, we surmounted them all and succeeded in securing approval to launch.”
The Planetary Society’s second LightSail spacecraft is scheduled to fly in 2016. This mission will build on the results of the test flight to conduct a full demonstration of solar sailing in Earth orbit. LightSail will be packaged inside a spacecraft called Prox-1 built by students at Georgia Tech. The spacecraft duo will be launched aboard a SpaceX Falcon Heavy rocket to an orbit of about 720 kilometers (450 miles).
The Planetary Society's solar sailing involvement was started by Society co-founder Louis Friedman more than a decade ago. The LightSail project is managed by Doug Stetson, founder and principal partner of the Space Science and Exploration Consulting Group.
“LightSail is truly ‘the people’s satellite.’ Thanks to our members, the dream of citizen supported solar sailing will become a reality; the vision goes back to our founders, Lou Friedman, Bruce Murray, and Carl Sagan. We encourage space fans worldwide to join us on LightSail’s journey. Together we can change the world.” Nye concluded.
Astronomers Discover First Multiple-Planet System From K2 (Press Release)
Astronomers using data from the NASA Kepler spacecraft's reborn K2 mission may have made its first discovery of a star with three exoplanets—planets that orbit stars other than our sun. A paper reporting this discovery has been submitted for publication in The Astrophysical Journal.
Ranging in size from fifty percent larger to a little more than twice the size of Earth, the possible planets orbit a star about half the size and mass of our sun. The outermost planet orbits on the warm edge of the habitable zone, the distance from a star where liquid water might exist on the surface of an orbiting planet.
"We are delighted to see the enthusiastic response for K2. The mission has extended the telescope's search capability to a new part of the sky, marking the first K2 exoplanet discovery less than a month ago, and now the possible discovery of the first K2 multiple-planet system," said Charles Sobeck, Kepler project manager at NASA's Ames Research Center in Moffett Field, CA. "We look forward to the outcome of the peer-review process of this latest result."
The star, called EPIC 2011367065, home to these possible planets is about 150 light-years away in the constellation Leo.
As NASA's Dawn spacecraft closes in on Ceres, new images show the dwarf planet at 27 pixels across, about three times better than the calibration images taken in early December. These are the first in a series of images that will be taken for navigation purposes during the approach to Ceres.
Over the next several weeks, Dawn will deliver increasingly better and better images of the dwarf planet, leading up to the spacecraft's capture into orbit around Ceres on March 6. The images will continue to improve as the spacecraft spirals closer to the surface during its 16-month study of the dwarf planet.
"We know so little about dwarf planet Ceres. Now, Dawn is ready to change that," said Marc Rayman, Dawn's chief engineer and mission director, based at NASA's Jet Propulsion Laboratory in Pasadena, California.
The best images of Ceres so far were taken by NASA's Hubble Space Telescope in 2003 and 2004. This most recent images from Dawn, taken January 13, 2015, at about 80 percent of Hubble resolution, are not quite as sharp. But Dawn's images will surpass Hubble's resolution at the next imaging opportunity, which will be at the end of January.
"Already, the [latest] images hint at first surface structures such as craters," said Andreas Nathues, lead investigator for the framing camera team at the Max Planck Institute for Solar System Research, Gottingen, Germany.
Ceres is the largest body in the main asteroid belt, which lies between Mars and Jupiter. It has an average diameter of 590 miles (950 kilometers), and is thought to contain a large amount of ice. Some scientists think it's possible that the surface conceals an ocean.
Dawn's arrival at Ceres will mark the first time a spacecraft has ever visited a dwarf planet.
"The team is very excited to examine the surface of Ceres in never-before-seen detail," said Chris Russell, principal investigator for the Dawn mission, based at the University of California, Los Angeles. "We look forward to the surprises this mysterious world may bring."
The spacecraft has already delivered more than 30,000 images and many insights about Vesta, the second most massive body in the asteroid belt. Dawn orbited Vesta, which has an average diameter of 326 miles (525 kilometers), from 2011 to 2012. Thanks to its ion propulsion system, Dawn is the first spacecraft ever targeted to orbit two deep-space destinations.
JPL manages the Dawn mission for NASA's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. The University of California, Los Angeles (UCLA) is responsible for overall Dawn mission science. Orbital Sciences Corp. in Dulles, Virginia, designed and built the spacecraft. The Dawn framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research, Gottingen, Germany, with significant contributions by German Aerospace Center (DLR), Institute of Planetary Research, Berlin, and in coordination with the Institute of Computer and Communication Network Engineering, Braunschweig. The Framing Camera project is funded by the Max Planck Society, DLR, and NASA/JPL. The Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team.
NASA’s New Horizons Spacecraft Begins First Stages of Pluto Encounter (Press Release)
NASA's New Horizons spacecraft recently began its long-awaited, historic encounter with Pluto. The spacecraft is entering the first of several approach phases that culminate July 14 with the first close-up flyby of the dwarf planet, 4.67 billion miles (7.5 billion kilometers) from Earth.
“NASA first mission to distant Pluto will also be humankind’s first close up view of this cold, unexplored world in our solar system,” said Jim Green, director of NASA’s Planetary Science Division at the agency’s Headquarters in Washington. “The New Horizons team worked very hard to prepare for this first phase, and they did it flawlessly.”
The fastest spacecraft when it was launched, New Horizons lifted off in January 2006. It awoke from its final hibernation period last month after a voyage of more than 3 billion miles, and will soon pass close to Pluto, inside the orbits of its five known moons. In preparation for the close encounter, the mission’s science, engineering and spacecraft operations teams configured the piano-sized probe for distant observations of the Pluto system that start Sunday, Jan. 25 with a long-range photo shoot.
The images captured by New Horizons’ telescopic Long-Range Reconnaissance Imager (LORRI) will give mission scientists a continually improving look at the dynamics of Pluto’s moons. The images also will play a critical role in navigating the spacecraft as it covers the remaining 135 million miles (220 million kilometers) to Pluto.
“We’ve completed the longest journey any spacecraft has flown from Earth to reach its primary target, and we are ready to begin exploring,” said Alan Stern, New Horizons principal investigator from Southwest Research Institute in Boulder, Colorado.
LORRI will take hundreds of pictures of Pluto over the next few months to refine current estimates of the distance between the spacecraft and the dwarf planet. Though the Pluto system will resemble little more than bright dots in the camera’s view until May, mission navigators will use the data to design course-correction maneuvers to aim the spacecraft toward its target point this summer. The first such maneuver could occur as early as March.
“We need to refine our knowledge of where Pluto will be when New Horizons flies past it,” said Mark Holdridge, New Horizons encounter mission manager at Johns Hopkins University’s Applied Physics Laboratory (APL) in Laurel, Maryland. “The flyby timing also has to be exact, because the computer commands that will orient the spacecraft and point the science instruments are based on precisely knowing the time we pass Pluto – which these images will help us determine.”
The “optical navigation” campaign that begins this month marks the first time pictures from New Horizons will be used to help pinpoint Pluto’s location.
Throughout the first approach phase, which runs until spring, New Horizons will conduct a significant amount of additional science. Spacecraft instruments will gather continuous data on the interplanetary environment where the planetary system orbits, including measurements of the high-energy particles streaming from the sun and dust-particle concentrations in the inner reaches of the Kuiper Belt. In addition to Pluto, this area, the unexplored outer region of the solar system, potentially includes thousands of similar icy, rocky small planets.
More intensive studies of Pluto begin in the spring, when the cameras and spectrometers aboard New Horizons will be able to provide image resolutions higher than the most powerful telescopes on Earth. Eventually, the spacecraft will obtain images good enough to map Pluto and its moons more accurately than achieved by previous planetary reconnaissance missions.
APL manages the New Horizons mission for NASA’s Science Mission Directorate in Washington. Alan Stern, of the Southwest Research Institute (SwRI), headquartered in San Antonio, is the principal investigator and leads the mission. SwRI 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. APL designed, built and operates the spacecraft.
Ten Years Ago, Huygens Probe Lands on Surface of Titan (Press Release)
Ten years ago, an explorer from Earth parachuted into the haze of an alien moon toward an uncertain fate. After a gentle descent lasting more than two hours, it landed with a thud on a frigid floodplain, surrounded by icy cobblestones. With this feat, the Huygens probe accomplished humanity's first landing on a moon in the outer solar system. Huygens was safely on Titan, the largest moon of Saturn.
These images of Saturn's moon Titan were taken on Jan. 14, 2005 by the Huygens probe at four different altitudes. The images are a flattened (Mercator) projection of the view from the descent imager/spectral radiometer on the probe as it landed on Titan's surface.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter. NASA supplied two instruments on the Huygens probe, the Descent Imager/Spectral Radiometer and the Gas Chromatograph Mass Spectrometer.
NASA Satellite Set to Get the Dirt on Soil Moisture (Press Release)
A new NASA satellite that will peer into the topmost layer of Earth's soils to measure the hidden waters that influence our weather and climate is in final preparations for a Jan. 29 dawn launch from California.
The Soil Moisture Active Passive(SMAP) mission will take the pulse of a key measure of our water planet: how freshwater cycles over Earth's land surfaces in the form of soil moisture. The mission will produce the most accurate, highest-resolution global maps ever obtained from space of the moisture present in the top 2 inches (5 centimeters) of Earth's soils. It also will detect and map whether the ground is frozen or thawed. This data will be used to enhance scientists' understanding of the processes that link Earth's water, energy and carbon cycles.
"With data from SMAP, scientists and decision makers around the world will be better equipped to understand how Earth works as a system and how soil moisture impacts a myriad of human activities, from floods and drought to weather and crop yield forecasts," said Christine Bonniksen, SMAP program executive with the Science Mission Directorate's Earth Science Division at NASA Headquarters in Washington. "SMAP's global soil moisture measurements will provide a new capability to improve our understanding of Earth's climate."
Globally, the volume of soil moisture varies between three and five percent in desert and arid regions, to between 40 and 50 percent in saturated soils. In general, the amount depends on such factors as precipitation patterns, topography, vegetation cover and soil composition. There are not enough sensors in the ground to map the variability in global soil moisture at the level of detail needed by scientists and decision makers. From space, SMAP will produce global maps with 6-mile (10-kilometer) resolution every two to three days.
Researchers want to measure soil moisture and its freeze/thaw state better for numerous reasons. Plants and crops draw water from the soil through their roots to grow. If soil moisture is inadequate, plants fail to grow, which over time can lead to reduced crop yields. Also, energy from the sun evaporates moisture in the soil, thereby cooling surface temperatures and also increasing moisture in the atmosphere, allowing clouds and precipitation to form more readily. In this way, soil moisture has a significant effect on both short-term regional weather and longer-term global climate.
In summer, plants in Earth's northern boreal regions -- the forests found in Earth's high northern latitudes -- take in carbon dioxide from the air and use it to grow, but lay dormant during the winter freeze period. All other factors being equal, the longer the growing season, the more carbon plants take in and the more effective forests are in removing carbon dioxide from the air. Since the start of the growing season is marked by the thawing and refreezing of water in soils, mapping the freeze/thaw state of soils with SMAP will help scientists more accurately account for how much carbon plants are removing from the atmosphere each year. This information will lead to better estimates of the carbon budget in the atmosphere and, hence, better assessments of future global warming.
SMAP data will enhance our confidence in projections of how Earth's water cycle will respond to climate change.
"Assessing future changes in regional water availability is perhaps one of the greatest environmental challenges facing the world today," said Dara Entekhabi, SMAP science team leader at the Massachusetts Institute of Technology in Cambridge. "Today's computer models disagree on how the water cycle -- precipitation, clouds, evaporation, runoff, soil water availability -- will increase or decrease over time and in different regions as our world warms. SMAP's higher-resolution soil moisture data will improve the models used to make daily weather and longer-term climate predictions."
SMAP also will advance our ability to monitor droughts, predict floods and mitigate the related impacts of these extreme events. It will allow the monitoring of regional deficits in soil moisture and provide critical inputs into drought monitoring and early warning systems used by resource managers. The mission's high-resolution observations of soil moisture will improve flood warnings by providing information on ground saturation conditions before rainstorms.
SMAP's two advanced instruments work together to produce soil moisture maps. Its active radar works much like a flash camera, but instead of transmitting visible light, it transmits microwave pulses that pass through clouds and moderate vegetation cover to the ground and measures how much of that signal is reflected back. Its passive radiometer operates like a natural-light camera, capturing emitted microwave radiation without transmitting a pulse. Unlike traditional cameras, however, SMAP's images are in the microwave range of the electromagnetic spectrum, which is invisible to the naked eye. Microwave radiation is sensitive to how much moisture is contained in the soil.
The two instruments share a large, lightweight reflector antenna that will be unfurled in orbit like a blooming flower and then spin at about 14 revolutions per minute. The antenna will allow the instruments to collect data across a 621-mile (1,000-kilometer) swath, enabling global coverage every two to three days.
SMAP's radiometer measurements extend and expand on soil moisture measurements currently made by the European Space Agency's Soil Moisture Ocean Salinity(SMOS) mission, launched in 2009. With the addition of a radar instrument, SMAP's soil moisture measurements will be able to distinguish finer features on the ground.
SMAP will launch from Vandenberg Air Force Base on a United Launch Alliance Delta II rocket and maneuver into a 426-mile (685-kilometer) altitude, near-polar orbit that repeats exactly every eight days. The mission is designed to operate at least three years.
SMAP is managed for NASA's Science Mission Directorate in Washington by the agency’s Jet Propulsion Laboratory (JPL) in Pasadena, California, with instrument hardware and science contributions made by NASA's Goddard Space Flight Center in Greenbelt, Maryland. JPL is responsible for project management, system engineering, radar instrumentation, mission operations and the ground data system. Goddard is responsible for the radiometer instrument. Both centers collaborate on science data processing and delivery to the Alaska Satellite Facility, in Fairbanks, and the National Snow and Ice Data Center, at the University of Colorado in Boulder, for public distribution and archiving. NASA's Launch Services Program at the agency’s Kennedy Space Center in Florida is responsible for launch management. JPL is managed for NASA by the California Institute of Technology in Pasadena.
