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NASA Wednesday informed the science community to prepare for a planned competition to select science instruments for a potential Europa lander. While a Europa lander mission is not yet approved by NASA, the agency's Planetary Science Division has funding in Fiscal Year 2017 to conduct the announcement of opportunity process. "The possibility of placing a lander on the surface of this intriguing icy moon, touching and exploring a world that might harbor life is at the heart of the Europa lander mission," said Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate in Washington. "We want the community to be prepared for this announcement of opportunity, because NASA recognizes the immense amount of work involved in preparing proposals for this potential future exploration." The community announcement provides advance notice of NASA's plan to hold a competition for instrument investigations for a potential Europa lander mission. Proposed investigations will be evaluated and selected through a two-step competitive process to fund development of a variety of relevant instruments and then to ensure the instruments are compatible with the mission concept. Approximately 10 proposals may be selected to proceed into a competitive Phase A. The Phase A concept study will be limited to approximately 12 months with a $1.5 million budget per investigation. At the conclusion of these studies, NASA may select some of these concepts to complete Phase A and subsequent mission phases. Investigations will be limited to those addressing the following science objectives, which are listed in order of decreasing priority: In early 2016, in response to a congressional directive, NASA's Planetary Science Division began a study to assess the science and engineering design of a future Europa lander mission. NASA routinely conducts such studies—known as Science Definition Team (SDT) reports—long before the start of any mission to gain an understanding of the challenges, feasibility and science value of the potential mission. The 21-member team began work almost one year ago, submitting a report to NASA on Feb. 7. The agency briefed the community on the Europa Lander SDT study at recent town halls at the 2017 Lunar and Planetary Science Conference (LPSC) at The Woodlands, Texas, and the Astrobiology Science Conference (AbSciCon) in Mesa, Arizona. The proposed Europa lander is separate from and would follow its predecessor—the Europa Clipper multiple flyby mission - which now is in preliminary design phase and planned for launch in the early 2020s. Arriving in the Jupiter system after a journey of several years, the spacecraft would orbit the planet about every two weeks, providing opportunities for 40 to 45 flybys in the prime mission. The Clipper spacecraft would image Europa's icy surface at high resolution, and investigate its composition and structure of its interior and icy shell. More information: To view the Europa Lander Science Definition Team report, see solarsystem.nasa.gov/europa/technical.cfm


Nasa may have pushed back launching manned Mars missions but it just moved up an explorative mission to a unique asteroid orbiting the sun between Mars and Jupiter. Dubbed 19 Psyche, the asteroid is made up almost entirely of nickel-iron metal. Nasa moved its plan to launch a mission to the metal asteroid by a year and is now planning to launch its discovery mission in the summer of 2022. The asteroid is also believed to contain various other metals such as gold, copper, platinum, cobalt, iridium and more. However, the iron alone is estimated to be worth around $10,000 quadrillion. Trending: Brain scans show how fathers are more attentive to daughters than sons "We challenged the mission design team to explore if an earlier launch date could provide a more efficient trajectory to the asteroid Psyche, and they came through in a big way," Jim Green, director of the Planetary Science Division at Nasa headquarters said in a statement. "This will enable us to fulfill our science objectives sooner and at a reduced cost." The new mission parameters also mean that the spacecraft is expected to arrive at the main asteroid belt in 2026, "four years earlier than the original timeline," according to Nasa. "The change in plans is a great boost for the team and the mission," said Psyche project manager Henry Stone at Nasa's Jet Propulsion Laboratory. "Our mission design team did a fantastic job coming up with this ideal launch opportunity." The Psyche spacecraft has also been upgraded for the mission and has been fitted with "very high-power solar array design," which will allow it to travel at faster speeds than is normal for larger spacecrafts. According to Nasa, the mission is aimed at the mysteries of how planets were formed. "The mission team seeks to determine whether Psyche is the core of an early planet, how old it is, whether it formed in similar ways to Earth's core, and what its surface is like," Nasa said. The space agency had originally announced that it would launch its Psyche discovery mission in 2023. "This mission would be a journey back in time to one of the earliest periods of planetary accretion, when the first bodies were not only differentiating, but were being pulverized, shredded, and accreted by collisions," Lindy Elkins-Tanton, lead scientist on the Nasa mission and the director of Arizona State University's School of Earth and Space Exploration, and her team said in a Lunar and Planetary conference in 2014. "It is also an exploration, by proxy, of the interiors of terrestrial planets and satellites today: we cannot visit a metallic core any other way." You may be interested in:


News Article | May 25, 2017
Site: phys.org

"We challenged the mission design team to explore if an earlier launch date could provide a more efficient trajectory to the asteroid Psyche, and they came through in a big way," said Jim Green, director of the Planetary Science Division at NASA Headquarters in Washington. "This will enable us to fulfill our science objectives sooner and at a reduced cost." The Discovery program announcement of opportunity had directed teams to propose missions for launch in either 2021 or 2023. The Lucy mission was selected for the first launch opportunity in 2021, and Psyche was to follow in 2023. Shortly after selection in January, NASA gave the direction to the Psyche team to research earlier opportunities. "The biggest advantage is the excellent trajectory, which gets us there about twice as fast and is more cost effective," said Principal Investigator Lindy Elkins-Tanton of Arizona State University in Tempe. "We are all extremely excited that NASA was able to accommodate this earlier launch date. The world will see this amazing metal world so much sooner." The revised trajectory is more efficient, as it eliminates the need for an Earth gravity assist, which ultimately shortens the cruise time. In addition, the new trajectory stays farther from the sun, reducing the amount of heat protection needed for the spacecraft. The trajectory will still include a Mars gravity assist in 2023. "The change in plans is a great boost for the team and the mission," said Psyche Project Manager Henry Stone at NASA's Jet Propulsion Laboratory, Pasadena, California. "Our mission design team did a fantastic job coming up with this ideal launch opportunity." The Psyche spacecraft is being built by Space Systems Loral (SSL), Palo Alto, California. In order to support the new mission trajectory, SSL redesigned the solar array system from a four-panel array in a straight row on either side of the spacecraft to a more powerful five-panel x-shaped design, commonly used for missions requiring more capability. Much like a sports car, by combining a relatively small spacecraft body with a very high-power solar array design, the Psyche spacecraft will speed to its destination at a faster pace than is typical for a larger spacecraft. "By increasing the size of the solar arrays, the spacecraft will have the power it needs to support the higher velocity requirements of the updated mission," said SSL Psyche Program Manager Steve Scott. Psyche, an asteroid orbiting the sun between Mars and Jupiter, is made almost entirely of nickel-iron metal. As such, it offers a unique look into the violent collisions that created Earth and the terrestrial planets. The Psyche Mission was selected for flight earlier this year under NASA's Discovery Program, a series of lower-cost, highly focused robotic space missions that are exploring the solar system. The scientific goals of the Psyche mission are to understand the building blocks of planet formation and explore firsthand a wholly new and unexplored type of world. The mission team seeks to determine whether Psyche is the core of an early planet, how old it is, whether it formed in similar ways to Earth's core, and what its surface is like. The spacecraft's instrument payload will include magnetometers, multispectral imagers, and a gamma ray and neutron spectrometer. Explore further: NASA announces two missions to study early solar system More information: For more information about NASA's Psyche mission go to www.nasa.gov/psyche


NASA's Psyche mission, which aims to visit and study a metal asteroid of the same name, will launch a year earlier than previously planned. On May 25, the U.S. space agency said that that the mission will launch in the summer of 2022 instead of the original October 2023 launch schedule. The probe is now set to arrive at the main asteroid belt in 2026, or four years earlier than initially planned. NASA's Planetary Science Division director Jim Green said that launching the mission at an earlier date will provide a more efficient trajectory, which would allow the mission to accomplish its science objectives earlier and at a lower cost. The spacecraft's new trajectory is more efficient because it no longer calls for an Earth gravity assist, which shortens the probe's travel time. The new trajectory will also keep the spacecraft farther from the sun, which will reduce the needed amount of heat protection. The new trajectory, though, will still require a Mars gravity assist by year 2023. To support the new trajectory, the Space Systems Loral (SSL) in California, which builds the spacecraft, made changes to the design of the solar array system. From having a four-panel array in a straight row on both of its sides, the probe would have more powerful five panels with x-shaped design, which is often used for missions that need more capability. Combining a relatively small body with high-powered solar arrays design would get the Psyche spacecraft to its target destination at a faster pace than when it is built with a larger body. The solar arrays will also give the spacecraft the power needed to support the higher velocity requirements of the mission. The Psyche mission is part of NASA's Discovery Program, a series of space missions to explore the solar system. It will particularly study the unique asteroid Psyche. The irregularly shaped asteroid, which measures about 130 miles in diameter, is one of the largest known asteroids. The object is also one of the most massive in the asteroid belt, having a little less than 1 percent of the entire asteroid belt's' total mass. Unlike most known asteroids in the solar system with rocky and icy bodies, Psyche is primarily made of pure nickel-iron metal. It is believed to be 90 percent iron and nickel and 10 percent silicate rock. It is also the only known core-like object in the solar system. NASA wants to study this body, as it could shed more light on the interiors and layers of planets and moons since Psyche could possibly be a planetary body whose outer layers were removed due to violent collisions with other objects billions of years ago. "This is an opportunity to explore a new type of world — not one of rock or ice, but of metal," Psyche Principal Investigator Lindy Elkins-Tanton said. "16 Psyche is the only known object of its kind in the solar system, and this is the only way humans will ever visit a core. We learn about inner space by visiting outer space." © 2017 Tech Times, All rights reserved. Do not reproduce without permission.


News Article | February 17, 2017
Site: www.scientificamerican.com

It’s not something NASA likes to advertise, but ever since its creation in 1958, the space agency has only conducted one direct, focused hunt for extraterrestrial life—and that was more than 40 years ago. It happened in 1976, when the twin Viking landers touched down at separate sites on Mars to look for any signs of life lurking on the planet’s desolate, freeze-dried surface. The Viking mission was—and still is—the most expensive planetary science mission ever launched as well as a technical tour de force that laid the foundations for all future interplanetary exploration. Both landers came up empty in their search for life, however, and ever since NASA has favored a series of missions—most of them to Mars—that transformed our understanding of our neighboring worlds as they tiptoed around the central question of whether any of them harbor life. Now, after decades of wandering in Martian deserts, NASA’s astrobiologists are at last preparing to rekindle a direct search for a “second genesis” of life in our solar system—but not where one might think. This time, they will look well beyond Mars, the most Earthlike of our planetary neighbors, to the dark reaches of the outer solar system, where probes and space telescopes have revealed ever-more tantalizing signs of oceans hidden inside icy moons and dwarf planets. Warmed by tidal forces rather than sunlight, those environments could harbor life, scientists say. “These oceans may be close to the surface, or may be deeper, with thicker ice crusts, but there must be water in liquid or slush form there—even all the way out to Pluto,” says James Green, director of NASA’s Planetary Science Division and an architect of the agency’s embryonic Ocean Worlds exploration program. The program’s central focus is Europa, a moon of Jupiter that despite being slightly smaller than Earth’s lunar companion is thought to contain an ocean twice as voluminous as all our planet’s seas combined. Data from previous spacecraft flybys hint Europa’s ocean is billions of years old and in direct contact with the moon’s hot, rocky core, offering life sufficient time and energy to get started somewhere within. Locked below a crust with an average thickness of at least dozens of kilometers, any Europan biosphere might have remained forever out of reach. Occasionally seawater wells up through fissures in the crust to freeze at or near the surface, however, and recent observations by the Hubble Space Telescope suggest the ocean may even be venting vast amounts of water vapor into space through geyserlike plumes erupting from beneath the surface. If astronomers could collect the frozen material or the vapor they might learn what, if anything, lurks within Europa. NASA is already developing a spacecraft set to launch in the 2020s called the Europa Multiple Flyby Mission. The EMFM will orbit Jupiter, swooping by Europa 45 times to study the reputed plumes, measure the thickness of the moon’s icy crust and map the surface at high resolution. Yet the EMFM is only a prelude. Heeding a directive handed down by Congress in 2015, the agency is studying concepts for a lander to touch down on Europa’s surface with the explicit purpose of gathering and studying samples in search of alien biology. A new study produced by a 21-member panel of biologists, geologists, space scientists and flight engineers describes the potential lander in detail, and projects it could land on Europa as early as 2031. “That’s what we really want to know,” Green says. “What’s in that ocean, and is it alive? The lander is really all about that next step… I would like to see the lander sitting under a plume—the plume sloshing on its deck, fresh material coming out of the crack. Now, are we there yet? Not quite.” Despite Congress’s clamor for NASA to explore Europa, there is no guarantee it will actually provide the agency with funding necessary for the mission, which is conspicuously bereft of a price tag. Cost estimates would come later, NASA officials say, after careful consultation with the scientific community, not to mention sympathetic and powerful members of Congress. Bob Pappalardo, a senior research scientist at NASA’s Jet Propulsion Laboratory (JPL) and EMFM’s project scientist, believes there is a compelling case to launch both the orbital and lander missions in rapid succession. “It’s like peanut butter and jelly—neither one makes a great sandwich by itself but they are wonderful together,” he says, adding that either mission would still be wonderful on its own. “The EMFM will get at the key questions of Europa’s global habitability—its geology, chemistry, surface variation and the locations of its liquid water. If you want to really go for the brass ring and search for signs of life, then you’ll need to follow up on those findings by zooming in and going down to the surface…. I thought this was so far off that we would not see it in our lifetimes. Now, I’m not so sure.” Jonathan Lunine remains skeptical. The Cornell University planetary scientist has seen too many mission proposals crash and burn long before they reach the launch pad to be overly optimistic about near-term prospects for a lander. “I want to see this happen in my scientific career, but we are at an early stage and so it is hard to predict when this will happen,” he says. “I’ve always found that the political process—getting approval and funding—represents the most hazardous environment a planetary mission can be exposed to.” Whenever—if ever—NASA’s mission planners green-light a life-seeking Europa lander, the specter of Viking’s pitfalls will loom over every challenge. How can it safely land? Where should it go? And above all, how should it search for alien life? Low-resolution orbital imagery and simplistic retrorockets forced the Viking landers to touch down on drab, boulder-strewn plains that proved unfavorable to the search for life. The landers carried three relatively crude life-detecting experiments conceived when genetics and microbial ecology were still in their infancy and when knowledge of the Martian environment was much more limited. Each experiment investigated soil samples for signs of organic metabolism, the chemical reactions organisms rely on to produce and use energy. The samples, though, were scraped directly from the surface where intense ultraviolet radiation and cosmic rays would have killed almost any conceivable microbe, eliminating potential metabolic signatures. These and other troubles ensured that instead of making a robust case for life on Mars, Viking’s experiments delivered confusing, conflicting results. In contrast, a Europa lander would have to rely on profoundly different technologies for landing, operating and looking for life, largely based on lessons learned from Viking. Before the lander even approached Europa, the EMFM’s high-resolution reconnaissance would help locate a compelling landing site—ideally a region of young ice enriched with fresh material from the ocean beneath, perhaps pushed up through cracks or falling like snow from a nearby plume. It would touch down using a “skycrane” like the one that gently placed NASA’s Curiosity rover on Mars in 2012, improving the odds of achieving a pinpoint landing in obstacle-filled terrain. “The greatest technical hurdle is designing a spacecraft that can safely land on a surface that is largely unknown,” says Curt Niebur, program scientist for NASA’s outer solar system missions. “But if we can meet the challenge of landing at Europa, then we can land anywhere.” Although mission planners have yet to map Europa at very high resolution, the lower-resolution images they have already seen show a topography rugged enough to give them nightmares, says Britney Schmidt, a planetary scientist at Georgia Tech and study co-author. “Icy surfaces on Earth are incredibly complex, and Europa is rough on every scale we’ve ever observed it, so finding a flat spot might be impossible,” she says. “It’s hard not to be worried about that. Mars has been difficult for us—and it’s way flatter than Europa.” Many of the most tantalizing landing spots may in fact also be the most dangerous—so called “chaos regions” defined by the jumbles of ridges, pits and fissures that sprawl haphazardly across them. Such regions may be sites where liquid water has come close to the surface through relatively thin crust, causing the ground above to collapse and shift due to cycles of melting and refreezing. Schmidt’s personal favorite site for a lander—and one of the leading candidates in the study—is Thera Macula, a chaos region near a possible plume source that also resides in a relatively radiation-free area of the Europan surface. If it makes it to the surface successfully, a Europa lander would deploy a sophisticated instrument package to characterize its surroundings and perform a much broader search for life than anything possible during the Viking era. Stereoscopic cameras would find targets for sample collection and seismometers would map the subsurface using the echoes from icequakes. Instead of focusing on metabolism, spectrometers and microscopes would look for the biochemical building blocks of life—organic molecules, perhaps even individual cells—in pristine samples carved or drilled by a robotic arm that could penetrate as much as ten centimeters beneath the moon’s surface. Despite benefiting from 40 years of technological and scientific progress, there is one key area in which the Europa lander will be at a distinct disadvantage in comparison to Viking. The Jovian moon is a far more alien place with fewer obvious similarities to Earth or to Mars to guide the design of experiments. “Europa is the right next place to ask the always-tough question about how life might be detected beyond Earth,” says Jim Garvin, chief scientist at NASA Goddard Space Flight Center and co-chair of the lander study team. “What makes this both exciting and daunting is engineering the necessary analytical measurements to occur in an environment that is outright ‘nasty’ in comparison to Mars.” At Europa’s equator, the average surface temperature hovers around a chilly –160 degrees Celsius, and the entire surface is continuously pummeled by deadly radiation from particles trapped in Jupiter’s immense magnetic field, not to mention the occasional incoming space rock. Most of the lander’s delicate instruments would be kept relatively warm and protected within a radiation-shielded vault, leaving little more than the robotic arm and cameras exposed. The lander would operate for perhaps a month before expiring on that cold, hostile surface. The mysterious aquatic world within Europa pushes standard concepts of habitability to extremes and demands an entirely new approach to searching for life. “The influence of abundant photosynthetic productivity permeates our atmosphere, oceans and upper crust, so our intuition about what an inhabited world looks like is very much couched in this context,” says Tori Hoehler, an astrobiologist at NASA Ames Research Center and co-author of the lander study. “A Europan biosphere, if one exists, is constrained by a very different set of environmental factors.” There can be no life-giving sunlight in Europa’s ocean, so organisms there, scientists believe, would probably be chemosynthetic rather than photosynthetic, much like the creatures that live at hydrothermal vents on Earth’s seafloor. Life in that cold, dark, briny abyss would likely be quite languorous, with biochemistry throttled by a relative paucity of usable energy and nutrients, analogous to the minimalist aquatic ecosystems found in Antarctica such as the subglacial Lake Vostok and the hypersaline Lake Vida. Unable to probe these undersea environments directly, the Europa lander would instead have to look for biological by-products that might suffuse the sea and become incorporated in surface ice. In a similar fashion, scientists can estimate deep-sea biological activity on Earth by measuring concentrations of cells and amino acids diluted in huge volumes of seawater. Based on such terrestrial measurements, the Europa study team set high standards for a lander’s life-seeking experiments, which must be able to discern organic material diluted to roughly one part per 50 billion and as few as 100 cells in a cubic centimeter of ice. “We basically wanted to have a very strong approach to understanding any ambiguous results,” explains Kevin Hand, a planetary scientist at JPL and co-chair of the lander study team. “If the lander finds no evidence of complex organics or cells of microbes in the ice, we’ll know that if there is life on Europa, it leaves only a faint bio-signature that is below the organic and cell count levels found in places like Antarctica’s Lake Vostok.” Such a result would be disappointing, but according to Hoehler and his co-authors the greater disappointment would be if it was perceived as a failure that stifled momentum for further missions to Europa and other icy moons. It would be unlikely for Europa to give up all its secrets to the very first lander that sets down there, and such a mission could be just the beginning for NASA’s Ocean Worlds program. Missions could someday explore subsurface seas in Saturn’s Enceladus and Titan, Neptune’s Triton or even deep down in Pluto. Sensing a coming sea change, optimistic researchers are already sketching out wild ideas like interplanetary submarines built to bore or melt through kilometers of ice. “Even if we somehow convinced ourselves that Europa wasn’t inhabited, and I don’t really think it's possible to do so,” Hoehler says, “it would remain an extraordinarily interesting place to understand.”


News Article | February 25, 2017
Site: news.yahoo.com

It’s taken a year and a half, but the International Astronomical Union and the science team behind NASA’s New Horizons mission have finally struck a deal for naming the features on Pluto and its moons. The agreement, announced today, will open the way for the already well-known “informal” names for places on Pluto, such as Tombaugh Regio and Sputnik Planum, to become formal. It also allows for features on Charon, Pluto’s biggest moon, to be officially associated with fictional characters and locales – including Mordor from “Lord of the Rings,” Mr. Spock from “Star Trek” and Princess Leia from “Star Wars.” The scheme is mostly based on names that were suggested even before New Horizons flew past Pluto on July 14, 2015, as part of the SETI Institute’s “Our Pluto” campaign. The IAU and the New Horizons team agreed on a few tweaks to the categories for Pluto and Charon. For example, the revised scheme allows for naming places on Pluto after pioneering space missions and spacecraft, and naming features on Charon after authors and artists associated with space exploration. Back in 2015, the IAU wasn’t willing to go along with those themes, because they were similar to themes used for Mercury, Venus and Mars. The revised scheme means that Sputnik Planum – the informal name for the bright left half of Pluto’s “heart” – and Kubrick Mons on Charon are more likely to be OK’d. Now the New Horizons team will go ahead and submit its dozens of informal names for the IAU’s approval, in accordance with the international body’s longstanding procedures. Some of the scientists on the New Horizons mission, including principal investigator Alan Stern, haven’t always gotten along with the IAU, which engineered the reclassification of Pluto as a dwarf planet in 2006. But today, both sides had good things to say about each other. “I’m very happy with both the process and partnership that New Horizons and the IAU undertook that led to wonderful, inspiring and engaging naming themes for surface features on Pluto and its moons,” Stern said in today’s announcement. The IAU’s Working Group for Planetary System Nomenclature will work with Stern and his colleagues to sign off on the formal names. “I am very pleased that the close collaboration of the WGPSN with the New Horizons Team led to these beautiful, inspirational categories for naming the features on Pluto and its satellites,” said Rita Schulz, who’s in charge of the working group. “We are ready now for receiving the proposals for names. Good things take time, but it will be worth it.” Here are the naming themes that have been approved for Pluto and its moons: The agreement means that some of the thousands of names that were suggested and voted on during the “Our Pluto” campaign could soon start appearing on official planetary maps. “Imagine the thrill of seeing your name suggestion on a future map of Pluto and its moons,” said Jim Green, director of NASA’s Planetary Science Division. “Months after the Pluto flyby, the New Horizons mission continues to engage and inspire.” New Horizons is now on its way to an encounter in 2019 with yet another icy object in the Kuiper Belt, currently known as 2014 MU69. Someday, that mini-world and its features will have to be given official names as well. Any suggestions?


News Article | February 25, 2017
Site: news.yahoo.com

On Thursday, the International Astronomical Union approved themes for naming surface features on Pluto and its moons. For the dwarf planet, most of the naming themes relate to the underworld. If someone asks you to pick a planet in our solar system that most resembles the Greek kingdom of the dead, which one would you choose? If your answer is Pluto, then congratulations, you now have something in common with the folks over at NASA and the International Astronomical Union (IAU). On Thursday, two years after the IAU endorsed NASA's “Our Pluto” naming campaign — which allowed the public to propose names for surface features that had still not been discovered — the agency approved themes submitted by NASA’s New Horizons team for naming surface features on Pluto and its moons. Not surprisingly, most of the naming themes for Pluto relate to the underworld. “Imagine the thrill of seeing your name suggestion on a future map of Pluto and its moons,” Jim Green, director of NASA’s Planetary Science Division in Washington, D.C., said in a statement released Thursday. “Months after the Pluto flyby, the New Horizons mission continues to engage and inspire.” Even prior to IAU’s imprimatur, astronomers associated with the New Horizons mission had been informally assigning similar names to newly discovered features on the dwarf planet — Krun Macula (Krun is the lord of the underworld in the ancient Mandaean religion, and a macula is a dark feature on a planetary surface), Tartarus Dorsa (In Greek mythology, Tartarus is the name of a region of the underworld where the greatest sinners are sent for their transgressions.) Pluto is a lot like what Hades’ realm is often portrayed as, minus the souls of dead humans, of course. It is dark, cold and barren, with temperatures ranging from -400 degrees Fahrenheit to about -360 degrees Fahrenheit. Here are the IAU-approved themes that the naming process would now stick to: Pluto ●    Gods, goddesses and other beings associated with the underworld from mythology, folklore and literature ●    Names for the underworld and for underworld locales from mythology, folklore and literature ●    Heroes and other explorers of the underworld ●    Scientists and engineers associated with Pluto and the Kuiper Belt ●    Pioneering space missions and spacecraft ●    Historic pioneers who crossed new horizons in the exploration of the Earth, sea and sky Charon ●    Destinations and milestones of fictional space and other exploration ●    Fictional and mythological vessels of space and other exploration ●    Fictional and mythological voyagers, travelers and explorers ●    Authors and artists associated with space exploration, especially Pluto and the Kuiper Belt For Pluto’s smaller moons: •    Styx: River gods •    Nix: Deities of the night •    Kerberos: Dogs from literature, mythology and history •    Hydra: Legendary serpents and dragons


News Article | February 15, 2017
Site: spaceref.biz

One of NASA's two new Discovery Program missions, Lucy will perform the first reconnaissance of the Jupiter Trojan asteroids orbiting the sun in tandem with the gas giant. The Lucy spacecraft will launch in 2021 to study six of these exciting worlds. The mission is led by Principal Investigator Dr. Harold Levison of the Southwest Research Institute in Boulder, Colorado. NASA's Goddard Space Flight Center in Greenbelt, Maryland will manage the mission. The program has a development cost cap of about $450 million. "This is a thrilling mission as the Jupiter Trojan asteroids have never been studied up close," said Guy Beutelschies, director of Interplanetary Systems at Lockheed Martin Space Systems. "The design of the spacecraft draws from the flight-proven OSIRIS-REx spacecraft currently on its way to a near-Earth asteroid. This heritage of spacecraft and mission operations brings known performance, reliability and cost to the mission." Lucy will study the geology, surface composition and bulk physical properties of these bodies at close range. It's slated to arrive at its first destination, a main belt asteroid, in 2025. From 2027 to 2033, Lucy will explore six Jupiter Trojan asteroids. These asteroids are trapped by Jupiter's gravity in two swarms that share the planet's orbit, one leading and one trailing Jupiter in its 12-year circuit around the sun. The Trojans are thought to be relics of a much earlier era in the history of the solar system, and may have formed far beyond Jupiter's current orbit. "This is a unique opportunity," said Dr. Levison. "Because the Trojans are remnants of the primordial material that formed the outer planets, they hold vital clues to deciphering the history of the solar system. Lucy, like the human fossil for which it is named, will revolutionize the understanding of our origins." Lucy is the seventh NASA Discovery Program mission in which Lockheed Martin has participated. Previously, the company developed the Lunar Prospector spacecraft; developed the aeroshell entry system for Mars Pathfinder; developed and operated the spacecraft for both Stardust missions; developed and operated the Genesis spacecraft; developed and operated the two GRAIL spacecraft; and developed and will operate the InSight Mars lander set to launch in May 2018. NASA's Discovery program class missions are relatively low-cost, their development capped at a specific cost. They are managed for NASA's Planetary Science Division by the Planetary Missions Program Office at Marshall Space Flight Center in Huntsville, Alabama. The missions are designed and led by a principal investigator, who assembles a team of scientists and engineers, to address key science questions about the solar system. About Lockheed Martin Headquartered in Bethesda, Maryland, Lockheed Martin is a global security and aerospace company that employs approximately 98,000 people worldwide and is principally engaged in the research, design, development, manufacture, integration and sustainment of advanced technology systems, products and services. Please follow SpaceRef on Twitter and Like us on Facebook.


News Article | February 19, 2017
Site: phys.org

"Juno is healthy, its science instruments are fully operational, and the data and images we've received are nothing short of amazing," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate in Washington. "The decision to forego the burn is the right thing to do—preserving a valuable asset so that Juno can continue its exciting journey of discovery." Juno has successfully orbited Jupiter four times since arriving at the giant planet, with the most recent orbit completed on Feb. 2. Its next close flyby of Jupiter will be March 27. The orbital period does not affect the quality of the science collected by Juno on each flyby, since the altitude over Jupiter will be the same at the time of closest approach. In fact, the longer orbit provides new opportunities that allow further exploration of the far reaches of space dominated by Jupiter's magnetic field, increasing the value of Juno's research. During each orbit, Juno soars low over Jupiter's cloud tops—as close as about 2,600 miles (4,100 kilometers). During these flybys, Juno probes beneath the obscuring cloud cover and studies Jupiter's auroras to learn more about the planet's origins, structure, atmosphere and magnetosphere. The original Juno flight plan envisioned the spacecraft looping around Jupiter twice in 53-day orbits, then reducing its orbital period to 14 days for the remainder of the mission. However, two helium check valves that are part of the plumbing for the spacecraft's main engine did not operate as expected when the propulsion system was pressurized in October. Telemetry from the spacecraft indicated that it took several minutes for the valves to open, while it took only a few seconds during past main engine firings. "During a thorough review, we looked at multiple scenarios that would place Juno in a shorter-period orbit, but there was concern that another main engine burn could result in a less-than-desirable orbit," said Rick Nybakken, Juno project manager at NASA's Jet Propulsion Laboratory in Pasadena, California. "The bottom line is a burn represented a risk to completion of Juno's science objectives." Juno's larger 53-day orbit allows for "bonus science" that wasn't part of the original mission design. Juno will further explore the far reaches of the Jovian magnetosphere—the region of space dominated by Jupiter's magnetic field—including the far magnetotail, the southern magnetosphere, and the magnetospheric boundary region called the magnetopause. Understanding magnetospheres and how they interact with the solar wind are key science goals of NASA's Heliophysics Science Division. "Another key advantage of the longer orbit is that Juno will spend less time within the strong radiation belts on each orbit," said Scott Bolton, Juno principal investigator from Southwest Research Institute in San Antonio. "This is significant because radiation has been the main life-limiting factor for Juno." Juno will continue to operate within the current budget plan through July 2018, for a total of 12 science orbits. The team can then propose to extend the mission during the next science review cycle. The review process evaluates proposed mission extensions on the merit and value of previous and anticipated science returns. The Juno science team continues to analyze returns from previous flybys. Revelations include that Jupiter's magnetic fields and aurora are bigger and more powerful than originally thought and that the belts and zones that give the gas giant's cloud top its distinctive look extend deep into the planet's interior. Peer-reviewed papers with more in-depth science results from Juno's first three flybys are expected to be published within the next few months. In addition, the mission's JunoCam—the first interplanetary outreach camera—is now being guided with assistance from the public. People can participate by voting on which features on Jupiter should be imaged during each flyby. "Juno is providing spectacular results, and we are rewriting our ideas of how giant planets work," said Bolton. "The science will be just as spectacular as with our original plan." Explore further: NASA's Juno spacecraft to make its fourth flyby over Jupiter


Burrows N.,Science Division | McCaw L.,Science Division
Frontiers in Ecology and the Environment | Year: 2013

Prescribed burning is an important but often controversial fire-management tool in fire-prone regions of the world. Here, we explore the complex challenges of prescribing fire for multiple objectives in the eucalypt forests of southwestern Australia, which could be regarded as a model for temperate landscapes elsewhere. Prescribed fire has been used in a coordinated manner to manage fuels in Australia's eucalypt forests since the 1950s and continues to be an important tool for mitigating the impacts of unplanned wildfires on human society and on a broad range of ecosystem services. Prescribed fire is increasingly being used to manage fire regimes at the local and landscape scales to achieve biodiversity outcomes through maintenance of spatial and temporal patterns of post-fire seral stages. The prescribed burning program in southwestern eucalypt forests has been informed by a long-term program of applied research into fire behavior and fire ecology. To remain successful in the future, the prescribed burning program in this region will need to adapt to changing expectations of government and the community, emerging land-use issues, resource limitations, and a drying climate. © The Ecological Society of America.

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