Tuesday, March 31, 2015

OSIRIS-REx Update: Assembly Officially Begins on the Spacecraft!

An artist's concept of NASA's OSIRIS-REx spacecraft preparing to take a sample from asteroid Bennu.
NASA / Goddard / Chris Meaney

NASA’s OSIRIS-REx Mission Passes Critical Milestone (Press Release)

NASA's groundbreaking science mission to retrieve a sample from an ancient space rock has moved closer to fruition. The Origins Spectral Interpretation Resource Identification Security Regolith Explorer (OSIRIS-REx) mission has passed a critical milestone in its path towards launch and is officially authorized to transition into its next phase.

Key Decision Point-D (KDP-D) occurs after the project has completed a series of independent reviews that cover the technical health, schedule and cost of the project. The milestone represents the official transition from the mission’s development stage to delivery of systems, testing and integration leading to launch. During this part of the mission’s life cycle, known as Phase D, the spacecraft bus, or the structure that will carry the science instruments, is completed, the instruments are integrated into the spacecraft and tested, and the spacecraft is shipped to NASA's Kennedy Space Center in Florida for integration with the rocket.

“This is an exciting time for the OSIRIS-REx team,” said Dante Lauretta, principal investigator for OSIRIS-Rex at the University of Arizona, Tucson. “After almost four years of intense design efforts, we are now proceeding with the start of flight system assembly. I am grateful for the hard work and team effort required to get us to this point.”

OSIRIS-REx is the first U.S. mission to return samples from an asteroid to Earth. The spacecraft will travel to a near-Earth asteroid called Bennu and bring at least a 60-gram (2.1-ounce) sample back to Earth for study. OSIRIS-REx carries five instruments that will remotely evaluate the surface of Bennu. The mission will help scientists investigate the composition of the very early solar system and the source of organic materials and water that made their way to Earth, and improve understanding of asteroids that could impact our planet.

OSIRIS-REx is scheduled for launch in late 2016. The spacecraft will reach Bennu in 2018 and return a sample to Earth in 2023.

"The spacecraft structure has been integrated with the propellant tank and propulsion system and is ready to begin system integration in the Lockheed Martin highbay,” said Mike Donnelly, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The payload suite of cameras and sensors is well into its environmental test phase and will be delivered later this summer/fall.”

The key decision meeting was held at NASA Headquarters in Washington on March 30 and chaired by NASA's Science Mission Directorate.

On March 27, assembly, launch and test operations officially began at Lockheed Martin in Denver. These operations represent a critical stage of the program when the spacecraft begins to take form, culminating with its launch. Over the next several months, technicians will install the subsystems on the main spacecraft structure, comprising avionics, power, telecomm, thermal systems, and guidance, navigation and control.

The next major milestone is the Mission Operations Review, scheduled for completion in June. The project will demonstrate that its navigation, planning, commanding, and science operations requirements are complete.

The mission's principal investigator is at the University of Arizona, Tucson. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, will provide overall mission management, systems engineering and safety and mission assurance for OSIRIS-REx. Lockheed Martin Space Systems in Denver will build the spacecraft. OSIRIS-REx is the third mission in NASA's New Frontiers Program. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages New Frontiers for the agency's Science Mission Directorate.

OSIRIS-REx complements NASA's Asteroid Initiative, which aligns portions of the agency's science, space technology and human exploration capabilities in a coordinated asteroid research effort. The initiative will conduct research and analysis to better characterize and mitigate the threat these space rocks pose to our home planet.

Included in the initiative is NASA's Asteroid Redirect Mission (ARM), a robotic spacecraft mission that will capture a boulder from the surface of a near-Earth asteroid and move it into a stable orbit around the moon for exploration by astronauts, all in support of advancing the nation’s journey to Mars. The agency also is engaging new industrial capabilities, partnerships, open innovation and participatory exploration through the NASA Asteroid Initiative.

NASA also has made tremendous progress in the cataloging and characterization of near Earth objects over the past five years. The president's NASA budget included, and Congress authorized, $20.4 million for an expanded NASA Near-Earth Object (NEO) Observations Program, increasing the resources for this critical program from the $4 million per year it had received since the 1990s. The program was again expanded in fiscal year 2014, with a budget of $40.5 million. NASA is asking Congress for $50 million for this important work in the 2016 budget.

NASA has identified more than 12,000 NEOs to date, including 96 percent of near-Earth asteroids larger than 0.6 miles (1 kilometer) in size. NASA has not detected any objects of this size that pose an impact hazard to Earth in the next 100 years. Smaller asteroids do pass near Earth, however, and some could pose an impact threat. In 2011, 893 near-Earth asteroids were found. In 2014, that number was increased to 1,472.

In addition to NASA's ongoing work detecting and cataloging asteroids, the agency has engaged the public in the hunt for these space rocks through the agency's Asteroid Grand Challenge activities, including prize competitions. During the recent South by Southwest Festival in Austin, Texas, the agency announced the release of a software application based on an algorithm created by a NASA challenge that has the potential to increase the number of new asteroid discoveries by amateur astronomers.

Source: NASA.Gov

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At the Lockheed Martin facility in Littleton, Colorado, engineers work on the OSIRIS-REx spacecraft after its core structure was combined with its hydrazine fuel tank and boat tail assembly.
Dante Lauretta - DSLauretta.com

Saturday, March 28, 2015

Back in the Day: Remembering Space Shuttle Endeavour's Voyage to LA...

An F-35A Lightning II flies above space shuttle Endeavour and her Shuttle Carrier Aircraft just as they were about to depart from Edwards Air Force Base in the Mojave Desert and head for Los Angeles...on September 21, 2012.
Lockheed Martin

Just thought I'd share these two cool pics I stumbled upon online as space shuttle Endeavour prepared to venture to her final resting home in Los Angeles back in September of 2012. In the photo above, an F-35A Lightning II soars over Endeavour and her Shuttle Carrier Aircraft as they were prepped for flight on the tarmac at Edwards Air Force Base in the Mojave Desert. In the image below, a visitor aboard the USS Iowa in San Pedro took this shot of the retired orbiter as she flew high above the battleship's mighty 16-inch guns (two of which are visible in this pic). Endeavour's permanent exhibit, the Samuel Oschin Air and Space Center, is set to open at the California Science Center in 2018. I'll be there when it opens...or soon thereafter.

Two of the USS Iowa's nine 16-inch guns are visible in this shot as space shuttle Endeavour and her Shuttle Carrier Aircraft soar high above the decommissioned battleship in San Pedro, California...on September 21, 2012.

Friday, March 20, 2015

MAVEN Update: Intriguing New Discoveries Made at the Red Planet...

An illustration depicting NASA's MAVEN spacecraft using its Imaging UltraViolet Spectrograph (IUVS) to study an aurora above Mars.
University of Colorado

NASA Spacecraft Detects Aurora and Mysterious Dust Cloud around Mars (Press Release - March 18)

NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft has observed two unexpected phenomena in the Martian atmosphere: an unexplained high-altitude dust cloud and aurora that reaches deep into the Martian atmosphere.

The presence of the dust at orbital altitudes from about 93 miles (150 kilometers) to 190 miles (300 kilometers) above the surface was not predicted. Although the source and composition of the dust are unknown, there is no hazard to MAVEN and other spacecraft orbiting Mars.

"If the dust originates from the atmosphere, this suggests we are missing some fundamental process in the Martian atmosphere," said Laila Andersson of the University of Colorado's Laboratory for Atmospherics and Space Physics (CU LASP), Boulder, Colorado.

The cloud was detected by the spacecraft’s Langmuir Probe and Waves (LPW) instrument, and has been present the whole time MAVEN has been in operation. It is unknown if the cloud is a temporary phenomenon or something long lasting. The cloud density is greatest at lower altitudes. However, even in the densest areas it is still very thin. So far, no indication of its presence has been seen in observations from any of the other MAVEN instruments.

Possible sources for the observed dust include dust wafted up from the atmosphere; dust coming from Phobos and Deimos, the two moons of Mars; dust moving in the solar wind away from the sun; or debris orbiting the sun from comets. However, no known process on Mars can explain the appearance of dust in the observed locations from any of these sources.

MAVEN's Imaging Ultraviolet Spectrograph (IUVS) observed what scientists have named "Christmas lights." For five days just before Dec. 25, MAVEN saw a bright ultraviolet auroral glow spanning Mars' northern hemisphere. Aurora, known on Earth as northern or southern lights, are caused by energetic particles like electrons crashing down into the atmosphere and causing the gas to glow.

"What's especially surprising about the aurora we saw is how deep in the atmosphere it occurs - much deeper than at Earth or elsewhere on Mars,” said Arnaud Stiepen, IUVS team member at the University of Colorado. “The electrons producing it must be really energetic."

The source of the energetic particles appears to be the sun. MAVEN's Solar Energetic Particle instrument detected a huge surge in energetic electrons at the onset of the aurora. Billions of years ago, Mars lost a global protective magnetic field like Earth has, so solar particles can directly strike the atmosphere. The electrons producing the aurora have about 100 times more energy than you get from a spark of house current, so they can penetrate deeply in the atmosphere.

The findings are being presented at the 46th Lunar and Planetary Science Conference in The Woodlands, Texas.

MAVEN was launched to Mars on Nov. 18, 2013, to help solve the mystery of how the Red Planet lost most of its atmosphere and much of its water. The spacecraft arrived at Mars on Sept. 21, and is four months into its one-Earth-year primary mission.

"The MAVEN science instruments all are performing nominally, and the data coming out of the mission are excellent," said Bruce Jakosky of CU LASP, Principal Investigator for the mission.

MAVEN is part of the agency's Mars Exploration Program, which includes the Opportunity and Curiosity rovers, the Mars Odyssey and Mars Reconnaissance Orbiter spacecraft currently orbiting the planet.

NASA's Mars Exploration Program seeks to characterize and understand Mars as a dynamic system, including its present and past environment, climate cycles, geology and biological potential. In parallel, NASA is developing the human spaceflight capabilities needed for its journey to Mars or a future round-trip mission to the Red Planet in the 2030’s.

MAVEN's principal investigator is based at the University of Colorado's Laboratory for Atmospheric and Space Physics, and NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the MAVEN project. Partner institutions include Lockheed Martin, the University of California at Berkeley, and NASA's Jet Propulsion Laboratory.

Source: NASA.Gov

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A map of auroral detections, made by MAVEN's IUVS instrument in December of 2014, overlaid on Mars’ surface.
University of Colorado

Thursday, March 19, 2015

SPP Update #2: More Cool Milestones for NASA's Mission to Our Sun...

An engineering model of the heat shield that will protect NASA's Solar Probe Plus spacecraft during its exploration of the sun's outer atmosphere.
Johns Hopkins University Applied Physics Laboratory

Solar Probe Plus Moves into Advanced Development (Press Release - March 18)

Solar Probe Plus — NASA’s ambitious mission to fly through and examine the sun’s atmosphere — has reached a key stage of development.

Solar Probe Plus will begin advanced design, development and testing — a step NASA designates as Phase C — following a successful design review in which an independent assessment board deemed that the mission team, led by the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., was ready to move ahead with full-scale spacecraft fabrication, assembly, integration and testing.

“Solar Probe Plus will fly closer to the sun than any spacecraft before it — almost 10 times closer to the sun than the planet Mercury — and this presents unprecedented technical challenges,” says Andrew Driesman, Solar Probe Plus project manager at APL. “Whether it was devising ways for a spacecraft to survive so close to the sun, or to collect data in such an extreme environment, the concept of an operational solar probe had challenged engineers and scientists for decades, and now we’re another step closer to making it happen.”

Set to launch in 2018, Solar Probe Plus will orbit the sun 24 times, closing in with the help of seven Venus flybys. At its closest passes the probe will speed 118 miles per second through the sun’s outer atmosphere, or corona, coming about 3.8 million miles (about 6.2 million kilometers) from the surface to explore a region — and face hazards — no other spacecraft has encountered. Solar Probe Plus will carry 10 science instruments specifically designed to help solve two key puzzles of solar physics: why the sun’s outer atmosphere is so much hotter than the sun’s visible surface, and what accelerates the solar wind that affects Earth and our solar system.

“The answers to these questions can be obtained only through in-situ measurements of the solar wind down in the corona,” says APL’s Nicky Fox, Solar Probe Plus project scientist. “Solar Probe Plus gets close enough to provide the missing links, with the right complement of instruments to make the measurements. For the first time, we will be able to go up and touch our star.”

APL, which manages the mission and leads the spacecraft fabrication and integration effort, has made significant progress on several enabling technologies, such as the carbon-carbon composite heat shield that will protect Solar Probe Plus from temperatures exceeding 2,500 degrees Fahrenheit and impacts from hypervelocity dust particles. Engineers have also built and tested a liquid-cooling system to keep the spacecraft’s solar arrays at safe operating temperature throughout the voyage, and spacecraft parts are undergoing high-velocity dust tests that simulate flights through swarms of high-energy particles near the sun.

“Solar Probe Plus is a pathfinder for voyages to other stars and will explore one of the last unexplored regions of the solar system, the solar corona, where space weather is born,” says Lika Guhathakurta, Solar Probe Plus program scientist at NASA Headquarters in Washington.

The Solar Probe Plus team includes engineers, scientists, technicians and other experts from government, academia and industry. The mission is part of NASA’s Living With a Star program, designed to learn more about the sun and its effects on planetary systems and human activities. NASA’s Goddard Space Flight Center in Greenbelt, Md., manages the program for the Science Mission Directorate at NASA Headquarters.

Source: John Hopkins Applied Physics Laboratory Website

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An art concept of Solar Probe Plus approaching the sun.
Johns Hopkins University Applied Physics Laboratory

Wednesday, March 18, 2015

And the Rocket That Will Launch SOLAR PROBE PLUS Towards the Sun Is...

An artist's concept of NASA's Solar Probe Plus spacecraft approaching the sun.
JHU / APL

NASA Awards Launch Services Contract for Solar Probe Plus Mission (Press Release)

NASA has selected United Launch Services LLC of Centennial, Colorado, to provide launch services for the agency’s Solar Probe Plus (SPP) mission.

The SPP spacecraft will launch aboard a Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. Launch is targeted for July 31, 2018, at the opening of a 20-day launch period. The total contract award amount for launch services is $389.1 million.

SPP will be the first mission to fly through the sun’s outer atmosphere -- the solar corona -- to examine two fundamental aspects of solar physics: why the corona is so much hotter than the sun’s surface, and what accelerates the solar wind that affects Earth and our solar system. Understanding these fundamental phenomena has been a top-priority science goal for more than five decades. SPP will orbit the sun 24 times, closing to within 3.9 million miles of its surface with the help of seven Venus flybys.

The Launch Services Program at NASA’s Kennedy Space Center in Florida is responsible for management and oversight of the Delta IV Heavy launch services for SPP. The Johns Hopkins University Applied Physics Laboratory is designing and building the spacecraft for NASA’s Living with a Star Program, managed by the agency’s Goddard Space Flight Center in Greenbelt, Maryland.

Source: Kennedy Space Center Newsletter

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A Delta IV Heavy rocket carrying the Orion spacecraft lifts off from Cape Canaveral Air Force Station in Florida...beginning Exploration Flight Test (EFT)-1 on December 5, 2014.
NASA / Sandra Joseph and Kevin O'Connell

Friday, March 13, 2015

New Horizons Just Keeps Hittin' Those Milestones...

The green line marks the path traveled by the New Horizons spacecraft as of 9:00 PM, Pacific Daylight Time, on March 13, 2015. It is 90.2 million miles, or less than 1 Astronomical Unit, from Pluto.
ABOVE: The green line marks the path traveled by the New Horizons spacecraft as of
9:00 PM, Pacific Daylight Time, on March 13, 2015. It is 90.2 million miles, or less than 1
Astronomical Unit (AU)
, from Pluto. Click
here to view the official webpage showing
where New Horizons is in space.


A Record Day for New Horizons (Press Release - March 12)

Next exit: Pluto!

After more than nine years in space, on a voyage taking it farther to its primary destination than any mission before it, NASA'’s New Horizons spacecraft is within one astronomical unit of Pluto – meaning it’s closer to Pluto than the Earth is to the Sun.

Speeding along at nearly 33,000 miles per hour, New Horizons sailed past its last symbolic deep space mile marker at about 5:20 p.m. EDT on March 10. An astronomical unit (AU) is the average distance between the Earth and Sun, about 93 million miles or 149 million kilometers. All told, New Horizons' epic journey from Earth to Pluto has covered almost 32 AU — about 3 billion miles.

"This is an amazing project — one that will go down in the history 21st century achievements," said New Horizons Principal Investigator Alan Stern, of Southwest Research Institute, Boulder, Colorado. "And the history-making is just beginning — in July we reach Pluto, humankind’s farthest exploration shore, to explore it and its fascinating system of moons for the first time!"

A Record Engine Burn

The New Horizons mission set another historic marker on March 10, performing the record-distance trajectory correction burn in the history of spaceflight. New Horizons was 2.96 billion miles (4.77 billion kilometers) from the Sun at the time of the maneuver; Voyager 2, the previous record-holder, was approximately 2.8 billion miles (4.5 billion kilometers) for its last engine burn near Neptune in August 1989.

Source: New Horizons Website

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An artist's concept of NASA's New Horizons spacecraft traveling past the dwarf planet Pluto and its largest moon, Charon.
NASA / JHU APL / SwRI / Steve Gribben

Thursday, March 12, 2015

Europa Isn't The ONLY Waterworld Orbiting Jupiter...

An artist's concept of aurorae being generated by Jupiter's moon Ganymede...which, like Europa, may harbor a large subsurface water ocean.
NASA / ESA

NASA’s Hubble Observations Suggest Underground Ocean on Jupiter's Largest Moon (Press Release)

NASA’s Hubble Space Telescope has the best evidence yet for an underground saltwater ocean on Ganymede, Jupiter’s largest moon. The subterranean ocean is thought to have more water than all the water on Earth's surface.

Identifying liquid water is crucial in the search for habitable worlds beyond Earth and for the search of life as we know it.

“This discovery marks a significant milestone, highlighting what only Hubble can accomplish,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at NASA Headquarters, Washington. “In its 25 years in orbit, Hubble has made many scientific discoveries in our own solar system. A deep ocean under the icy crust of Ganymede opens up further exciting possibilities for life beyond Earth.”

Ganymede is the largest moon in our solar system and the only moon with its own magnetic field. The magnetic field causes aurorae, which are ribbons of glowing, hot electrified gas, in regions circling the north and south poles of the moon. Because Ganymede is close to Jupiter, it is also embedded in Jupiter’s magnetic field. When Jupiter’s magnetic field changes, the aurorae on Ganymede also change, “rocking” back and forth.

By watching the rocking motion of the two aurorae, scientists were able to determine that a large amount of saltwater exists beneath Ganymede’s crust affecting its magnetic field.

A team of scientists led by Joachim Saur of the University of Cologne in Germany came up with the idea of using Hubble to learn more about the inside of the moon.

"I was always brainstorming how we could use a telescope in other ways," said Saur. "Is there a way you could use a telescope to look inside a planetary body? Then I thought, the aurorae! Because aurorae are controlled by the magnetic field, if you observe the aurorae in an appropriate way, you learn something about the magnetic field. If you know the magnetic field, then you know something about the moon’s interior."

If a saltwater ocean were present, Jupiter’s magnetic field would create a secondary magnetic field in the ocean that would counter Jupiter’s field. This “magnetic friction” would suppress the rocking of the aurorae. This ocean fights Jupiter's magnetic field so strongly that it reduces the rocking of the aurorae to 2 degrees, instead of the 6 degrees, if the ocean was not present.

Scientists estimate the ocean is 60 miles (100 kilometers) thick – 10 times deeper than Earth's oceans – and is buried under a 95-mile (150-kilometer) crust of mostly ice.

Scientists first suspected an ocean in Ganymede in the 1970s, based on models of the large moon. NASA's Galileo mission measured Ganymede's magnetic field in 2002, providing the first evidence supporting those suspicions. The Galileo spacecraft took brief "snapshot" measurements of the magnetic field in 20-minute intervals, but its observations were too brief to distinctly catch the cyclical rocking of the ocean’s secondary magnetic field.

The new observations were done in ultraviolet light and could only be accomplished with a space telescope high above the Earth's atmosphere, which blocks most ultraviolet light.

NASA’s Hubble Space Telescope is celebrating 25 years of groundbreaking science on April 24. It has transformed our understanding of our solar system and beyond, and helped us find our place among the stars. To join the conversation about 25 years of Hubble discoveries, use the hashtag #Hubble25.

Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.

Source: NASA.Gov

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A composite image of aurorae being generated by Jupiter's moon Ganymede...which, like Europa, may harbor a large subsurface water ocean.
NASA / ESA

Wednesday, March 11, 2015

Another Awesome Discovery at Enceladus...

An artist's concept of water plumes being emitted from the surface of Saturn's moon Enceladus.
NASA / JPL

Spacecraft Data Suggest Saturn Moon's Ocean May Harbor Hydrothermal Activity (Press Release)

NASA's Cassini spacecraft has provided scientists the first clear evidence that Saturn’s moon Enceladus exhibits signs of present-day hydrothermal activity which may resemble that seen in the deep oceans on Earth. The implications of such activity on a world other than our planet open up unprecedented scientific possibilities.

“These findings add to the possibility that Enceladus, which contains a subsurface ocean and displays remarkable geologic activity, could contain environments suitable for living organisms,” said John Grunsfeld, astronaut and associate administrator of NASA's Science Mission Directorate in Washington. “The locations in our solar system where extreme environments occur in which life might exist may bring us closer to answering the question: are we alone in the Universe.”

Hydrothermal activity occurs when seawater infiltrates and reacts with a rocky crust and emerges as a heated, mineral-laden solution, a natural occurrence in Earth’s oceans. According to two science papers, the results are the first clear indications an icy moon may have similar ongoing active processes.

The first paper, published this week in the journal Nature, relates to microscopic grains of rock detected by Cassini in the Saturn system. An extensive, four-year analysis of data from the spacecraft, computer simulations and laboratory experiments led researchers to the conclusion the tiny grains most likely form when hot water containing dissolved minerals from the moon's rocky interior travels upward, coming into contact with cooler water. Temperatures required for the interactions that produce the tiny rock grains would be at least 194 degrees Fahrenheit (90 degrees Celsius).

"It's very exciting that we can use these tiny grains of rock, spewed into space by geysers, to tell us about conditions on -- and beneath -- the ocean floor of an icy moon," said the paper’s lead author Sean Hsu, a postdoctoral researcher at the University of Colorado at Boulder.

Cassini's cosmic dust analyzer (CDA) instrument repeatedly detected miniscule rock particles rich in silicon, even before Cassini entered Saturn’s orbit in 2004. By process of elimination, the CDA team concluded these particles must be grains of silica, which is found in sand and the mineral quartz on Earth. The consistent size of the grains observed by Cassini, the largest of which were 6 to 9 nanometers, was the clue that told the researchers a specific process likely was responsible.

On Earth, the most common way to form silica grains of this size is hydrothermal activity under a specific range of conditions; namely, when slightly alkaline and salty water that is super-saturated with silica undergoes a big drop in temperature.

"We methodically searched for alternate explanations for the nanosilica grains, but every new result pointed to a single, most likely origin," said co-author Frank Postberg, a Cassini CDA team scientist at Heidelberg University in Germany.

Hsu and Postberg worked closely with colleagues at the University of Tokyo who performed the detailed laboratory experiments that validated the hydrothermal activity hypothesis. The Japanese team, led by Yasuhito Sekine, verified the conditions under which silica grains form at the same size Cassini detected. The researchers think these conditions may exist on the seafloor of Enceladus, where hot water from the interior meets the relatively cold water at the ocean bottom.

The extremely small size of the silica particles also suggests they travel upward relatively quickly from their hydrothermal origin to the near-surface sources of the moon's geysers. From seafloor to outer space, a distance of about 30 miles (50 kilometers), the grains spend a few months to a few years in transit, otherwise they would grow much larger.

The authors point out that Cassini's gravity measurements suggest Enceladus' rocky core is quite porous, which would allow water from the ocean to percolate into the interior. This would provide a huge surface area where rock and water could interact.

The second paper, recently published in Geophysical Research Letters, suggests hydrothermal activity as one of two likely sources of methane in the plume of gas and ice particles that erupts from the south polar region of Enceladus. The finding is the result of extensive modeling by French and American scientists to address why methane, as previously sampled by Cassini, is curiously abundant in the plume.

The team found that, at the high pressures expected in the moon's ocean, icy materials called clathrates could form that imprison methane molecules within a crystal structure of water ice. Their models indicate that this process is so efficient at depleting the ocean of methane that the researchers still needed an explanation for its abundance in the plume.

In one scenario, hydrothermal processes super-saturate the ocean with methane. This could occur if methane is produced faster than it is converted into clathrates. A second possibility is that methane clathrates from the ocean are dragged along into the erupting plumes and release their methane as they rise, like bubbles forming in a popped bottle of champagne.

The authors agree both scenarios are likely occurring to some degree, but they note that the presence of nanosilica grains, as documented by the other paper, favors the hydrothermal scenario.

"We didn't expect that our study of clathrates in the Enceladus ocean would lead us to the idea that methane is actively being produced by hydrothermal processes," said lead author Alexis Bouquet, a graduate student at the University of Texas at San Antonio. Bouquet worked with co-author Hunter Waite, who leads the Cassini Ion and Neutral Mass Spectrometer (INMS) team at Southwest Research Institute in San Antonio.

Cassini first revealed active geological processes on Enceladus in 2005 with evidence of an icy spray issuing from the moon's south polar region and higher-than-expected temperatures in the icy surface there. With its powerful suite of complementary science instruments, the mission soon revealed a towering plume of water ice and vapor, salts and organic materials that issues from relatively warm fractures on the wrinkled surface. Gravity science results published in 2014 strongly suggested the presence of a 6-mile- (10-kilometer-) deep ocean beneath an ice shell about 19 to 25 miles (30 to 40 kilometers) thick.

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA's Jet Propulsion Laboratory in Pasadena, California, manages the mission for the agency’s Science Mission Directorate in Washington. The Cassini CDA instrument was provided by the German Aerospace Center. The instrument team, led by Ralf Srama, is based at the University of Stuttgart in Germany.

Source: NASA.Gov

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An infographic that shows how hydrothermal processes take place inside the subsurface water ocean of Enceladus.
Southwest Research Institute

Tuesday, March 10, 2015

Onward to Pluto: 'Only' 93 Million Miles to Go!

The green line marks the path traveled by the New Horizons spacecraft as of 5:00 PM, Pacific Daylight Time, on March 10, 2015. It is 93 million miles, or 1 Astronomical Unit, from Pluto.
ABOVE: The green line marks the path traveled by the New Horizons spacecraft as of
5:00 PM, Pacific Daylight Time, on March 10, 2015. It is 93 million miles, or 1 Astronomical
Unit (AU)
, from Pluto. Click
here to view the official webpage showing where New
Horizons
is in space.


With Trajectory Correction, NASA’s New Horizons Homes in on Pluto (Press Release)

A 93-second thruster burst today slightly adjusted the New Horizons spacecraft’s trajectory toward Pluto.

This was the first maneuver of New Horizons’ approach phase to Pluto; it was planned to slow the spacecraft’s velocity by just 1.14 meters per second – barely a tap on the brakes for a probe moving about 14.5 kilometers per second – and moved its July 14 arrival time back on schedule with a change from the pre-burn course of 14 minutes and 30 seconds. It will also shift the course “sideways” (if looking from Earth) by 3,442 kilometers (2,139 miles) by July 14, sending the spacecraft toward a desired flyby close-approach target point. The shift was based on the latest orbit predictions of Pluto and its largest moon Charon, estimated from various sources, including optical-navigation images of the Pluto system taken by New Horizons in January and February.

Using commands transmitted to the spacecraft on March 8, the thrusters began firing at 5:15 a.m. EDT, and stopped just 93 seconds later. Initial telemetry later indicated the spacecraft was healthy and fired on command reached the New Horizons Mission Operations Center at APL through NASA’s Deep Space Network at noon EDT; detailed data from the spacecraft’s Guidance and Control system – which will show the team how accurately the maneuver performed as designed – is expected later today.

Source: New Horizons Website

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An artist's concept of NASA's New Horizons spacecraft traveling past the dwarf planet Pluto and its largest moon, Charon.
NASA / JHU APL / SwRI / Steve Gribben

Monday, March 09, 2015

Moving Closer to Launch: LightSail Is Now at Cape Canaveral!

An artist's concept of The Planetary Society's LightSail spacecraft orbiting the Earth.
The Planetary Society

New Details Released for Citizen-Funded LightSail Spacecraft Launch (Press Release)

LightSail Arrives in Florida for May 6 Test Flight

Pasadena, CA (March 9, 2015) The Planetary Society’s privately funded LightSail spacecraft has arrived in Cape Canaveral, Fla., where it will be integrated with an Atlas V rocket scheduled to launch no earlier than May 6. The spacecraft is part of a secondary payload dubbed ULTRASat, which will fly aboard the U.S. Air Force mission AFSPC-5.

Bill Nye (The Science Guy), CEO at The Planetary Society, issued the following statement:

Our LightSail cubesat passed every one of its tests and has been loaded into its launcher mechanism. I’m naturally happy and excited, but I admit, a bit nervous. We've been working to get a solar sail into space since I joined The Planetary Society Board in 1997. It’s quite a milestone. Deep breath, no turning back now, this baby's on its own now. Here we go...

For complete coverage of the LightSail test flight, as well as the second LightSail mission scheduled for 2016, visit sail.planetary.org.

Source: The Planetary Society

Friday, March 06, 2015

Dawn's Moment of Triumph Has Arrived... Welcome to Ceres!

An image of the dwarf planet Ceres that was taken by NASA's Dawn spacecraft from a distance of about 30,000 miles (48,000 kilometers), on March 1, 2015.
NASA / JPL - Caltech / UCLA / MPS / DLR / IDA

NASA Spacecraft Becomes First to Orbit a Dwarf Planet (Press Release)

NASA's Dawn spacecraft has become the first mission to achieve orbit around a dwarf planet. The spacecraft was approximately 38,000 miles (61,000) kilometers from Ceres when it was captured by the dwarf planet’s gravity at about 4:39 a.m. PST (7:39 a.m. EST) Friday.

Mission controllers at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California received a signal from the spacecraft at 5:36 a.m. PST (8:36 a.m. EST) that Dawn was healthy and thrusting with its ion engine, the indicator Dawn had entered orbit as planned.

"Since its discovery in 1801, Ceres was known as a planet, then an asteroid and later a dwarf planet," said Marc Rayman, Dawn chief engineer and mission director at JPL. "Now, after a journey of 3.1 billion miles (4.9 billion kilometers) and 7.5 years, Dawn calls Ceres, home."

In addition to being the first spacecraft to visit a dwarf planet, Dawn also has the distinction of being the first mission to orbit two extraterrestrial targets. From 2011 to 2012, the spacecraft explored the giant asteroid Vesta, delivering new insights and thousands of images from that distant world. Ceres and Vesta are the two most massive residents of our solar system’s main asteroid belt between Mars and Jupiter.

The most recent images received from the spacecraft, taken on March 1 show Ceres as a crescent, mostly in shadow because the spacecraft's trajectory put it on a side of Ceres that faces away from the sun until mid-April. When Dawn emerges from Ceres' dark side, it will deliver ever-sharper images as it spirals to lower orbits around the planet.

"We feel exhilarated," said Chris Russell, principal investigator of the Dawn mission at the University of California, Los Angeles (UCLA). "We have much to do over the next year and a half, but we are now on station with ample reserves, and a robust plan to obtain our science objectives."

Dawn's mission is managed by JPL 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. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team.

For a complete list of mission participants, visit:

http://dawn.jpl.nasa.gov/mission

Source: NASA.Gov

Thursday, March 05, 2015

Red Planet Puzzle: How Wet Was Mars in the Past?

An artist's concept of an ancient ocean on Mars.
NASA / GSFC

NASA Research Suggests Mars Once Had More Water than Earth’s Arctic Ocean (Press Release)

A primitive ocean on Mars held more water than Earth’s Arctic Ocean, according to NASA scientists who, using ground-based observatories, measured water signatures in the Red Planet’s atmosphere.

Scientists have been searching for answers to why this vast water supply left the surface. Details of the observations and computations appear in Thursday’s edition of Science magazine.

“Our study provides a solid estimate of how much water Mars once had, by determining how much water was lost to space,” said Geronimo Villanueva, a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the new paper. “With this work, we can better understand the history of water on Mars.”

Perhaps about 4.3 billion years ago, Mars would have had enough water to cover its entire surface in a liquid layer about 450 feet (137 meters) deep. More likely, the water would have formed an ocean occupying almost half of Mars’ northern hemisphere, in some regions reaching depths greater than a mile (1.6 kilometers).

The new estimate is based on detailed observations made at the European Southern Observatory’s Very Large Telescope in Chile, and the W.M. Keck Observatory and NASA Infrared Telescope Facility in Hawaii. With these powerful instruments, the researchers distinguished the chemical signatures of two slightly different forms of water in Mars’ atmosphere. One is the familiar H2O. The other is HDO, a naturally occurring variation in which one hydrogen is replaced by a heavier form, called deuterium.

By comparing the ratio of HDO to H2O in water on Mars today and comparing it with the ratio in water trapped in a Mars meteorite dating from about 4.5 billion years ago, scientists can measure the subsequent atmospheric changes and determine how much water has escaped into space.

The team mapped H2O and HDO levels several times over nearly six years, which is equal to approximately three Martian years. The resulting data produced global snapshots of each compound, as well as their ratio. These first-of-their-kind maps reveal regional variations called microclimates and seasonal changes, even though modern Mars is essentially a desert.

The research team was especially interested in regions near Mars’ north and south poles, because the polar ice caps hold the planet’s largest known water reservoir. The water stored there is thought to capture the evolution of Mars’ water during the wet Noachian period, which ended about 3.7 billion years ago, to the present.

From the measurements of atmospheric water in the near-polar region, the researchers determined the enrichment, or relative amounts of the two types of water, in the planet’s permanent ice caps. The enrichment of the ice caps told them how much water Mars must have lost – a volume 6.5 times larger than the volume in the polar caps now. That means the volume of Mars’ early ocean must have been at least 20 million cubic kilometers (5 million cubic miles).

Based on the surface of Mars today, a likely location for this water would be in the Northern Plains, considered a good candidate because of the low-lying ground. An ancient ocean there would have covered 19 percent of the planet’s surface. By comparison, the Atlantic Ocean occupies 17 percent of Earth’s surface.

“With Mars losing that much water, the planet was very likely wet for a longer period of time than was previously thought, suggesting it might have been habitable for longer,” said Michael Mumma, a senior scientist at Goddard and the second author on the paper.

NASA is studying Mars with a host of spacecraft and rovers under the agency’s Mars Exploration Program, including the Opportunity and Curiosity rovers, Odyssey and Mars Reconnaissance Orbiter spacecraft, and the MAVEN orbiter, which arrived at the Red Planet in September 2014 to study the planet’s upper atmosphere.

In 2016, a Mars lander mission called InSight will launch to take a first look into the deep interior of Mars. The agency also is participating in ESA’s (European Space Agency) 2016 and 2018 ExoMars missions, including providing telecommunication radios to ESA’s 2016 orbiter and a critical element of the astrobiology instrument on the 2018 ExoMars rover. NASA’s next rover, heading to Mars in 2020, will carry instruments to conduct unprecedented science and exploration technology investigations on the Red Planet.

NASA’s Mars Exploration Program seeks to characterize and understand Mars as a dynamic system, including its present and past environment, climate cycles, geology and biological potential. In parallel, NASA is developing the human spaceflight capabilities needed for future round-trip missions to Mars in the 2030s.

Source: NASA.Gov

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Wednesday, March 04, 2015

InSight Update - Launch: T-Minus 1 Year and Counting...

Engineers at Lockheed Martin test the robotic arm of NASA's InSight lander...set to launch towards Mars on March 4, 2016.
NASA / JPL - Caltech

Single Site on Mars Advanced for 2016 NASA Lander (Press Release)

NASA's next mission to Mars, scheduled to launch one year from today to examine the Red Planet's deep interior and investigate how rocky planets like Earth evolved, now has one specific site under evaluation as the best place to land and deploy its science instruments.

The mission called InSight -- an acronym for "Interior Exploration using Seismic Investigations, Geodesy and Heat Transport" -- is scheduled to launch from Vandenberg Air Force Base, California. The launch period runs from March 4 to March 30, 2016, and will mark the first California launch of an interplanetary mission. Installation of science-instrument hardware onto the spacecraft has begun and a key review has given thumbs up to integration and testing of the mission's component systems from several nations participating in the international project.

The landing-site selection process evaluated four candidate locations selected in 2014. The quartet is within the flat-lying "Elysium Planitia," less than five degrees north of the equator, and all four appear safe for InSight's landing. The single site will continue to be analyzed in coming months for final selection later this year. If unexpected problems with this site are found, one of the others would be imaged and could be selected. The favored site is centered at about four degrees north latitude and 136 degrees east longitude.

"This is wondrous terrain, exactly what we want to land on because it is smooth, flat, with very few rocks in the highest-resolution images," said InSight's site-selection leader, Matt Golombek of NASA's Jet Propulsion Laboratory, Pasadena, California.

Mars orbiters have provided detailed information about the candidate sites, which are mapped as landing ellipses about 81 miles (130 kilometers) west-to-east by about 17 miles (27 kilometers) north-to-south. An ellipse covers the area within which InSight has odds of about 99 percent of landing, if targeted for the ellipse center. Several types of terrain, such as "cratered," "etched" and "smooth" were mapped in each ellipse. The one chosen for final evaluations has highest proportion in the smooth category.

After InSight reaches Mars on Sept. 28, 2016, the mission will assess properties of the planet's crust, mantle and core. The interior of Mars has not been churned as much as Earth's because Mars lacks the tectonic activity that recycles Earth's crustal plates back into the mantle. Thus, Mars offers an opportunity to find clues no longer present on Earth about how rocky planets such as Earth, Mars, Venus and Mercury formed and evolved.

InSight's primary science will study the planet's interior, not surface features. Besides safety for the landing, the main site-selection criterion is for the ground within reach of the lander's robotic arm to be penetrable for a heat-flow probe designed to hammer itself into the soil to a depth three to five yards, or meters.

Evidence that the ground will be suitable for the probe, rather than rock solid, comes from assessment by the Thermal Imaging System on NASA's Mars Odyssey orbiter of how quickly the ground cools at night or warms in sunlight, and evaluation of images from the High Resolution Imaging Science Experiment on NASA's Mars Reconnaissance Orbiter.

The heat-flow probe is a key part of InSight's Heat Flow and Physical Properties Package (HP3) provided by the German Aerospace Center (DLR). Electronics for that instrument were the first hardware from the science payload put onto the InSight spacecraft being assembled and tested at Lockheed Martin Space Systems, Denver.

"As flight components such as the HP3 electronics become available, our team continues to integrate them on the spacecraft and test their functionality," said Stu Spath, InSight spacecraft program manager at Lockheed Martin. "We're steadily marching toward the start of spacecraft environmental testing this spring."

InSight's robotic arm will also place another science instrument onto the ground. This is the Seismic Experiment for Interior Structure, or SEIS, from the French Space Agency (CNES), with components from Germany, Switzerland, the United Kingdom and the United States.

A third experiment will use the radio link between InSight and NASA's Deep Space Network antennas on Earth to measure precisely a wobble in Mars' rotation that could reveal whether the planet has a molten or solid core. Wind and temperature sensors from Spain's Center for Astrobiology and a pressure sensor will monitor weather, and a magnetometer will measure magnetic disturbances.

The project passed its System Integration Review in February. "A panel of experts from outside the project reviewed the system-level integration and test program," said InSight Project Manager Tom Hoffman, of JPL. "For Insight, there are multiple systems being brought together from several countries for final integration and testing in Denver."

InSight and other NASA current and future projects will help inform the journey to Mars, an agency priority to send humans to the Red Planet in the 2030s.

JPL manages InSight for NASA's Science Mission Directorate in Washington. InSight is part of NASA's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

Source: Jet Propulsion Laboratory

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NASA / JPL - Caltech

Tuesday, March 03, 2015

Hayabusa2 Update: Things Are Lookin' Good So Far...

An artist's concept of the Hayabusa 2 spacecraft obtaining soil samples from the surface of asteroid 1999 JU3.
JAXA

Hayabusa 2 Moving to Cruising Phase While Heading to Asteroid 1999 JU3 (Press Release)

The Asteroid Explorer Hayabusa 2 completed its initial functional confirmation period on March 2, 2015, as all scheduled checkout and evaluation of acquired data were completed. The explorer has been under inspection for about three months after its launch on December 3, 2014.

The Hayabusa 2 is moving to the cruising phase while heading to the asteroid "1999 JU3" on March 3. It will be under preparatory operation for an Earth swing-by scheduled in November or December, 2015.

We plan to increase the cruising speed of the explorer (60 m/sec.) by operating two ion engines twice (in total about 600 hours or 25 days) until the Earth swing-by. For the first operation, we will gradually increase the time duration of continuous ion-engine operation from March 3, and will operate the engines for about 400 hours within March. The second operation is scheduled in early June.

The Hayabusa 2 is in good health.

We would like to express our profound appreciation to all pertinent parties who have supported and cooperated with our initial functional confirmation operation. Your further and continued support will be highly appreciated for this long-term space exploration mission of the Hayabusa 2.

Source: Japan Aerospace Exploration Agency

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JAXA

Monday, March 02, 2015

Dawn Approaches Ceres: T-Minus 4 Days and Counting!

Two images of the dwarf planet Ceres that were taken by NASA's Dawn spacecraft from a distance of about 25,000 miles (40,000 kilometers), on February 25, 2015.
NASA / JPL - Caltech / UCLA / MPS / DLR / IDA

NASA Spacecraft Nears Historic Dwarf Planet Arrival (Press Release)

NASA's Dawn spacecraft has returned new images captured on approach to its historic orbit insertion at the dwarf planet Ceres. Dawn will be the first mission to successfully visit a dwarf planet when it enters orbit around Ceres on Friday, March 6.

"Dawn is about to make history," said Robert Mase, project manager for the Dawn mission at NASA's Jet Propulsion Laboratory in Pasadena, California. "Our team is ready and eager to find out what Ceres has in store for us."

Recent images show numerous craters and unusual bright spots that scientists believe tell how Ceres, the first object discovered in our solar system's asteroid belt, formed and whether its surface is changing. As the spacecraft spirals into closer and closer orbits around the dwarf planet, researchers will be looking for signs that these strange features are changing, which would suggest current geological activity.

"Studying Ceres allows us to do historical research in space, opening a window into the earliest chapter in the history of our solar system," said Jim Green, director of NASA's Planetary Science Division at the agency's Headquarters in Washington. "Data returned from Dawn could contribute significant breakthroughs in our understanding of how the solar system formed."

Dawn began its final approach phase toward Ceres in December. The spacecraft has taken several optical navigation images and made two rotation characterizations, allowing Ceres to be observed through its full nine-hour rotation. Since Jan. 25, Dawn has been delivering the highest-resolution images of Ceres ever captured, and they will continue to improve in quality as the spacecraft approaches.

Sicilian astronomer Father Giuseppe Piazzi spotted Ceres in 1801. As more such objects were found in the same region, they became known as asteroids, or minor planets. Ceres was initially classified as a planet and later called an asteroid. In recognition of its planet-like qualities, Ceres was designated a dwarf planet in 2006, along with Pluto and Eris.

Ceres is named for the Roman goddess of agriculture and harvests. Craters on Ceres will similarly be named for gods and goddesses of agriculture and vegetation from world mythology. Other features will be named for agricultural festivals.

Launched in September 2007, Dawn explored the giant asteroid Vesta for 14 months in 2011 and 2012, capturing detailed images and data about that body. Both Vesta and Ceres orbit the sun between Mars and Jupiter, in the main asteroid belt. This two-stop tour of our solar system is made possible by Dawn's ion propulsion system, its three ion engines being much more efficient than chemical propulsion.

"Both Vesta and Ceres were on their way to becoming planets, but their development was interrupted by the gravity of Jupiter," said Carol Raymond, deputy project scientist at JPL. "These two bodies are like fossils from the dawn of the solar system, and they shed light on its origins."

Ceres and Vesta have several important differences. Ceres is the most massive body in the asteroid belt, with an average diameter of 590 miles (950 kilometers). Ceres' surface covers about 38 percent of the area of the continental United States. Vesta has an average diameter of 326 miles (525 kilometers), and is the second most massive body in the belt. The asteroid formed earlier than Ceres and is a very dry body. Ceres, in contrast, is estimated to be 25 percent water by mass.

"By studying Vesta and Ceres, we will gain a better understanding of the formation of our solar system, especially the terrestrial planets and most importantly the Earth," said Raymond. "These bodies are samples of the building blocks that have formed Venus, Earth and Mars. Vesta-like bodies are believed to have contributed heavily to the core of our planet, and Ceres-like bodies may have provided our water."

"We would not be able to orbit and explore these two worlds without ion propulsion," Mase said. "Dawn capitalizes on this innovative technology to deliver big science on a small budget."

In addition to the Dawn mission, NASA will launch in 2016 its Origins-Spectral Interpretation-Resource Identification-Security-Regolith Explorer (OSIRIS-REx) spacecraft. This mission will study a large asteroid in unprecedented detail and return samples to Earth.

NASA also places a high priority on tracking and protecting Earth from asteroids. NASA's Near-Earth Object (NEO) Program at the agency's headquarters manages and funds the search, study and monitoring of asteroids and comets whose orbits periodically bring them close to Earth. NASA is pursuing an Asteroid Redirect Mission (ARM), which will identify, redirect and send astronauts to explore an asteroid. Among its many exploration goals, the mission could demonstrate basic planetary defense techniques for asteroid deflection.

Dawn's mission is managed by JPL 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. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft.

The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team. For a complete list of mission participants, visit:

http://dawn.jpl.nasa.gov/mission

Source: Jet Propulsion Laboratory

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