NASA’s New Horizons: A “Heart” from Pluto as Flyby Begins

NASA - New Horizons Mission logo.

July 8, 2015

Image above: This image of Pluto from New Horizons’ Long Range Reconnaissance Imager (LORRI) was received on July 8, and has been combined with lower-resolution color information from the Ralph instrument. Image Credits: NASA-JHUAPL-SWRI.

After a more than nine-year, three-billion-mile journey to Pluto, it’s show time for NASA’s New Horizons spacecraft, as the flyby sequence of science observations is officially underway.

In the early morning hours of July 8, mission scientists received this new view of Pluto—the most detailed yet returned by the Long Range Reconnaissance Imager (LORRI) aboard New Horizons. The image was taken on July 7, when the spacecraft was just under 5 million miles (8 million kilometers) from Pluto, and is the first to be received since the July 4 anomaly that sent the spacecraft into safe mode.

This view is centered roughly on the area that will be seen close-up during New Horizons’ July 14 closest approach. This side of Pluto is dominated by three broad regions of varying brightness. Most prominent are an elongated dark feature at the equator, informally known as “the whale,” and a large heart-shaped bright area measuring some 1,200 miles (2,000 kilometers) across on the right. Above those features is a polar region that is intermediate in brightness.

“The next time we see this part of Pluto at closest approach, a portion of this region will be imaged at about 500 times better resolution than we see today,” said Jeff Moore, Geology, Geophysics and Imaging Team Leader of NASA’s Ames Research Center. “It will be incredible!”

NASA's New Horizons spacecraft arrives at Pluto on July 14th

Video above: NASA's New Horizons spacecraft arrives at Pluto on July 14th; a journey lasting nearly 10 years and traveling over 3 billion miles. Watch coverage of the historic flyby of Pluto on NASA Television as NASA counts down to the Pluto encounter of a lifetime.
http://www.nasa.gov/multimedia/nasatv/index.html

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft, and manages the mission for NASA's Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

For more information about New Horizons mission, visit: http://www.nasa.gov/mission_pages/newhorizons/main/index.html

Image (mentioned), Video, Text, Credits: NASA/Tricia Talbert/NASA TV.

Best regards, Orbiter.ch

Typhoon Chan-Hom "Eyes" NASA's Aqua Satellite

NASA - Aqua Mission logo.

July 8, 2015

Chan-Hom - Northwest Pacific Ocean

Image above: When Aqua passed over Typhoon Chan-Hom on July 8 at 04:25 UTC (12:25 a.m. EDT), MODIS captured a visible-light image of the storm that clearly showed its eye. Image Credits: NASA Goddard MODIS Rapid Response Team.

Typhoon Chan-Hom's eye was visible from space when NASA's Aqua satellite passed overhead early on July 8, 2015.

The MODIS instrument, known as the Moderate Resolution Imaging Spectrometer, flies aboard NASA's Aqua satellite. When Aqua passed over Typhoon Chan-Hom on July 8 at 04:25 UTC (12:25 a.m. EDT), MODIS captured a visible-light image of the storm that clearly showed its eye. The MODIS image also a ring of powerful thunderstorms surrounding the eye of the storm, and the bulk of thunderstorms wrapping around the system from west to east, along the southern side.

At 0900 UTC (5 a.m. EDT), Typhoon Chan-Hom's maximum sustained winds were near 85 knots (97.8 mph/157.4 kph). Tropical-storm-force winds extended 145 nautical miles (166.9 miles/268.5 km) from the center, making the storm almost 300 nautical miles (345 miles/555 km) in diameter. Typhoon-force winds extended out to 35 nautical miles (40 miles/64.8 km) from the center.

Chan-Hom's eye was centered near 20.5 North latitude and 132.7 East longitude, about 450 nautical miles (517.9 miles/833.4 km) southeast of Kadena Air Base, Iwo To, Japan. Chan-Hom was moving to the northwest at 11 knots (12.6 mph/20.3 kph). The typhoon was generating very rough seas with wave heights to 28 feet (8.5 meters). 

The Aqua Satellite. Image Credit: NASA

The Joint Typhoon Warning Center expects Chan-Hom to continue tracking northwestward over the next three days under the steering influence of a sub-tropical ridge (elongated area of high pressure). Chan-Hom is expected to intensify steadily peaking at 120 knots (138.1 mph/222.2 kph) on July 10. The JTWC forecast predicts that Chan-Hom will make landfall near Wenzhou, Zhejiang, China and begin decaying due to land interaction.

For updated warnings and watches from China's National Meteorological Centre, visit: http://www.cma.gov.cn/en/WeatherWarnings/.

For more information about Aqua satellite mission, visit: http://aqua.nasa.gov/

Images (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Rob Gutro.

Greetings, Orbiter.ch

Searing Sun Seen in X-rays

NASA - NuSTAR Mission patch.

July 8, 2015

X-rays light up the surface of our sun in a bouquet of colors in this new image containing data from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR. The high-energy X-rays seen by NuSTAR are shown in blue, while green represents lower-energy X-rays from the X-ray Telescope instrument on the Hinode spacecraft, named after the Japanese word for sunrise. The yellow and red colors show ultraviolet light from NASA's Solar Dynamics Observatory.

NuSTAR usually spends its time investigating the mysteries of black holes, supernovae, and other high-energy objects in space. But it can also look closer to home to study our sun.

Image above: Flaring, active regions of our sun are highlighted in this new image combining observations from several telescopes. High-energy X-rays from NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) are shown in blue; low-energy X-rays from Japan's Hinode spacecraft are green; and extreme ultraviolet light from NASA's Solar Dynamics Observatory (SDO) is yellow and red. Image Credits: NASA/JPL-Caltech/GSFC/JAXA.

"We can see a few active regions on the sun in this view," said Iain Hannah of the University of Glasgow, Scotland, who presented the image today, July 8, at the Royal Astronomical Society's National Astronomy Meeting in Llandudno, Wales. "Our sun is quieting down in its activity cycle, but still has a couple of years before it reaches a minimum."

Those active areas of the sun are filled with flares, which are giant eruptions on the surface of the sun that spew out charged particles and high-energy radiation. They occur when magnetic field lines become tangled and broken, and then reconnect. Due to its extreme sensitivity, NuSTAR's telescope cannot view the larger flares. But it can help measure the energy of smaller microflares, which produce only one-millionth the energy of the larger flares.

NuSTAR may also be able to directly detect hypothesized nanoflares, which would be only one-billionth the energy of flares. Nanoflares -- which may help explain why the sun's atmosphere, or corona, is much hotter than expected -- would be hard to spot due to their small size. However, nanoflares may emit high-energy X-rays that NuSTAR has the sensitivity to detect. Astronomers suspect that these tiny flares, like their larger brethren, can send electrons flying at tremendous velocities. As the electrons zip around, they give off high-energy X-rays.

"We still need the sun to quiet down more over the next few years to have the ability to detect these events," said Hannah, explaining that, while our sun is approaching the tranquil end of its roughly 11-year activity cycle, it has been showing spurious bouts of high activity.

Astronomers are also excited to use NuSTAR's images of the sun to pinpoint where energy from flares is released. While it is known that the energy is generally liberated in the upper solar atmosphere, the locations and detailed mechanisms are not precisely known.

Nuclear Spectroscopic Telescope Array, or NuSTAR. Image Credits: NASA/JPL-Caltech

Cosmologists are looking forward to using NuSTAR's solar observations, too. There is a slim chance the telescope could detect a hypothesized dark matter particle called the axion. Dark matter is a mysterious substance in our universe that is about five times more abundant than the regular matter that makes up everyday objects and anything that gives off light. NuSTAR might be able to address this and other mysteries of the sun.

"What's great about NuSTAR is that the telescope is so versatile that we can hunt black holes millions of light-years away and we can also learn something fundamental about the star in our own backyard," said Brian Grefenstette of the California Institute of Technology in Pasadena, an astronomer on the NuSTAR team.

NuSTAR is a Small Explorer mission led by Caltech and managed by NASA's Jet Propulsion Laboratory in Pasadena, California, for NASA's Science Mission Directorate in Washington. NuSTAR was developed in partnership with the Danish Technical University and the Italian Space Agency (ASI). The spacecraft was built by Orbital Sciences Corp., Dulles, Virginia. NuSTAR's mission operations center is at UC Berkeley, and the official data archive is at NASA's High Energy Astrophysics Science Archive Research Center. ASI provides the mission's ground station and a mirror archive. JPL is managed by Caltech for NASA.

The Hinode mission is led by the Japanese Aerospace Exploration Agency, with participation from NASA and European partners.

For more information about NuStar, visit: http://www.nasa.gov/nustar and http://www.nustar.caltech.edu

Images (mentioned), Text, Credits: NASA/JPL/Whitney Clavin/Tony Greicius.

Best regards, Orbiter.ch

Second Instrument Delivered for NASA’s OSIRIS-REx Mission

NASA - Osiris-REx Mission logo.

July 8, 2015

An instrument that will explore the surface of a primitive asteroid in search of water and organic materials has arrived at Lockheed Martin Space Systems in Denver for installation onto NASA’s Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx).

"The OVIRS team has met all of their technical requirements," said Mike Donnelly, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This is another step in completing the spacecraft and sending it on its way to rendezvous with the asteroid Bennu."

Image above: The OSIRIS-REx Visible and Infrared Spectrometer (OVIRS) will measure visible and near infrared light from the asteroid Bennu. The instrument's observations could be used to identify water and organic materials. This image shows OVIRS at NASA's Goddard Space Flight Center in Greenbelt, Maryland, where it was built, prior to shipping to Lockheed Martin Space Systems in Denver. Image Credits: NASA Goddard/Bill Hrybyk.

The OSIRIS-REx Visible and Infrared Spectrometer (OVIRS) measures visible and near infrared light from Bennu, which can be used to identify water and organic materials. Goddard built the instrument.

OVIRS, a point spectrometer, will split the light from the asteroid Bennu into its component wavelengths, similar to a prism that splits sunlight into a rainbow, but over a much broader range of wavelengths. Different chemicals have unique spectral signatures by absorbing sunlight and can be identified in the reflected spectrum. The spectra provided by the instrument will help guide sample site selection.

“Through the team’s efforts, OVIRS has become a remarkably capable instrument which we expect to return exciting science from the asteroid, Bennu,” said Dennis Reuter, OVIRS instrument lead from Goddard.

After thorough testing with the spacecraft on the ground, the instrument will be powered on for check-out shortly after launch, with first science data collected during the Earth gravity assist in September 2017.

Image above: Artist concept of OSIRIS-REx satellite. Image Credits: NASA's Goddard Space Flight Center.

OSIRIS-REx is the first U.S. mission to return samples from an asteroid to Earth for study. The mission is scheduled for launch in September 2016. It will reach its asteroid target in 2018 and return a sample to Earth in 2023.

The spacecraft will travel to a near-Earth asteroid, called Bennu and bring at least a 2.1-ounce sample back to Earth for study. 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.

“The delivery of OVIRS to the spacecraft means the mission now has the capability to measure the minerals and chemicals at the sample site on Bennu,” said Dante Lauretta, principal investigator for OSIRIS-REx at the University of Arizona, Tucson. “I greatly appreciate the hard work and innovation the OVIRS team demonstrated during the creation of this instrument.”

NASA's Goddard Space Flight Center in Greenbelt, Maryland, provides overall mission management, systems engineering and safety and mission assurance for OSIRIS-REx. Dante Lauretta is the mission's principal investigator at the University of Arizona, Tucson. Lockheed Martin Space Systems in Denver is building 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 in Washington.

For more information on OSIRIS-REx visit: http://www.nasa.gov/osiris-rex and http://www.asteroidmission.org

Images (mentioned), Text, Credits: NASA’s Goddard Space Flight Center/Nancy Neal Jones/Rob Garner.

Cheers, Orbiter.ch

Biggest Explosions in the Universe Powered by Strongest Magnets

ESO - European Southern Observatory logo.

8 July 2015

Some long-duration gamma-ray bursts are driven by magnetars

Observations from ESO’s La Silla and Paranal Observatories in Chile have for the first time demonstrated a link between a very long-lasting burst of gamma rays and an unusually bright supernova explosion. The results show that the supernova was not driven by radioactive decay, as expected, but was instead powered by the decaying super-strong magnetic fields around an exotic object called a magnetar. The results will appear in the journal Nature on 9 July 2015.

Gamma-ray bursts (GRBs) are one of the outcomes associated with the biggest explosions to have taken place since the Big Bang. They are detected by orbiting telescopes that are sensitive to this type of high-energy radiation, which cannot penetrate the Earth’s atmosphere, and then observed at longer wavelengths by other telescopes both in space and on the ground.

 Artist’s impression of a gamma-ray burst and supernova powered by a magnetar

GRBs usually only last a few seconds, but in very rare cases the gamma rays continue for hours [1]. One such ultra-long duration GRB was picked up by the Swift satellite on 9 December 2011 and named GRB 111209A. It was both one of the longest and brightest GRBs ever observed.

As the afterglow from this burst faded it was studied using both the GROND instrument on the MPG/ESO 2.2-metre telescope at La Silla and also with the X-shooter instrument on the Very Large Telescope (VLT) at Paranal. The clear signature of a supernova, later named SN 2011kl, was found. This is the first time that a supernova has been found to be associated with an ultra-long GRB [2].

The lead author of the new paper, Jochen Greiner from the Max-Planck-Institut für extraterrestrische Physik, Garching, Germany explains: “Since a long-duration gamma-ray burst is produced only once every 10 000–100 000 supernovae, the star that exploded must be somehow special. Astronomers had assumed that these GRBs came from very massive stars — about 50 times the mass of the Sun — and that they signalled the formation of a black hole. But now our new observations of the supernova SN 2011kl, found after the GRB 111209A, are changing this paradigm for ultra-long duration GRBs.”

In the favoured scenario of a massive star collapse (sometimes known as a collapsar) the week-long burst of optical/infrared emission from the supernova is expected to come from the decay of radioactive nickel-56 formed in the explosion [3]. But in the case of GRB 111209A the combined GROND and VLT observations showed unambiguously for the first time that this could not be the case [4]. Other suggestions were also ruled out [5].

The only explanation that fitted the observations of the supernova following GRB 111209A was that it was being powered by a magnetar — a tiny neutron star spinning hundreds of times per second and possessing a magnetic field much stronger than normal neutron stars, which are also known as radio pulsars [6]. Magnetars are thought to be the most strongly magnetised objects in the known Universe. This is the first time that such an unambiguous connection between a supernova and a magnetar has been possible.

Paolo Mazzali, co-author of the study, reflects on the significance of the new findings: “The new results provide good evidence for an unexpected relation between GRBs, very bright supernovae and magnetars. Some of these connections were already suspected on theoretical grounds for some years, but linking everything together is an exciting new development."

“The case of SN 2011kl/GRB 111209A forces us to consider an alternative to the collapsar scenario. This finding brings us much closer to a new and clearer picture of the workings of GRBs," concludes Jochen Greiner.

Notes:

[1] Normal long-duration GRBs last between 2 and 2000 seconds. There are now four GRBs known with durations between 10 000–25 000 seconds — these are called ultra-long GRBs. There is also a distinct class of shorter-duration GRBs that are believed to be created by a different mechanism.

[2] The link between supernovae and (normal) long-duration GRBs was established initially in 1998, mainly by observations at ESO observatories of the supernova SN 1998bw, and confirmed in 2003 with GRB 030329.

[3] The GRB itself is thought to be powered by the relativistic jets produced by the star's material collapsing onto the central compact object via a hot, dense accretion disc.

[4] The amount of nickel-56 measured in the supernova with the GROND instrument is much too large to be compatible with the strong ultraviolet emission as seen with the X-shooter instrument.

[5] Other suggested sources of energy to explain superluminous supernovae were shock interactions with the surrounding material — possibly linked to stellar shells ejected before the explosion — or a blue supergiant progenitor star. In the case of SN 2011kl the observations clearly exclude both of these options.

[6] Pulsars make up the most common class of observable neutron stars, but magnetars are thought to develop magnetic field strengths that are 100 to 1000 times greater than those seen in pulsars.

More information:

This research was presented in a paper entitled “A very luminous magnetar-powered supernova associated with an ultra-long gamma-ray burst”, by J. Greiner et al., to appear in the journal Nature on 9 July 2015.

The team is composed of Jochen Greiner (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany [MPE]; Excellence Cluster Universe, Technische Universität München, Garching, Germany), Paolo A. Mazzali (Astrophysics Research Institute, Liverpool John Moores University, Liverpool, England; Max-Planck-Institut für Astrophysik, Garching, Germany [MPA]), D. Alexander Kann (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany), Thomas Krühler (ESO, Santiago, Chile) , Elena Pian (INAF, Institute of Space Astrophysics and Cosmic Physics, Bologna, Italy; Scuola Normale Superiore, Pisa, Italy), Simon Prentice (Astrophysics Research Institute, Liverpool John Moores University, Liverpool, England), Felipe Olivares E. (Departamento de Ciencias Fisicas, Universidad Andres Bello, Santiago, Chile), Andrea Rossi (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany; INAF, Institute of Space Astrophysics and Cosmic Physics, Bologna, Italy), Sylvio Klose (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany) , Stefan Taubenberger (MPA; ESO, Garching, Germany), Fabian Knust (MPE), Paulo M.J. Afonso (American River College, Sacramento, California, USA), Chris Ashall (Astrophysics Research Institute, Liverpool John Moores University, Liverpool, England), Jan Bolmer (MPE; Technische Universität München, Garching, Germany), Corentin Delvaux (MPE), Roland Diehl (MPE), Jonathan Elliott (MPE; Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA), Robert Filgas (Institute of Experimental and Applied Physics, Czech Technical University in Prague, Prague, Czech Republic), Johan P.U. Fynbo (DARK Cosmology Center, Niels-Bohr-Institut, University of Copenhagen, Denmark), John F. Graham (MPE), Ana Nicuesa Guelbenzu (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany), Shiho Kobayashi (Astrophysics Research Institute, Liverpool John Moores University, Liverpool, England), Giorgos Leloudas (DARK Cosmology Center, Niels-Bohr-Institut, University of Copenhagen, Denmark; Department of Particle Physics & Astrophysics, Weizmann Institute of Science, Israel), Sandra Savaglio (MPE; Universita della Calabria, Italy), Patricia Schady (MPE), Sebastian Schmidl (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany), Tassilo Schweyer (MPE; Technische Universität München, Garching, Germany), Vladimir Sudilovsky (MPE; Harvard-Smithonian Center for Astrophysics, Cambridge, Massachusetts, USA), Mohit Tanga (MPE), Adria C. Updike (Roger Williams University, Bristol, Rhode Island, USA), Hendrik van Eerten (MPE) and Karla Varela (MPE).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

Research paper: http://www.eso.org/public/archives/releases/sciencepapers/eso1527/eso1527a.pdf

Photos of the VLT: http://www.eso.org/public/images/archive/category/paranal/

Information about the GROND instrument: http://www.mpe.mpg.de/~jcg/GROND/

Very Large Telescope (VLT): http://www.eso.org/paranal/

Gamma-ray bursts (GRBs): https://en.wikipedia.org/wiki/Gamma-ray_burst

Max-Planck-Institut für extraterrestrische Physik: http://www.mpe.mpg.de/

Swift satellite: http://swift.gsfc.nasa.gov/

Image, Text, Credit: European Southern Observatory (ESO).

Greetings, Orbiter.ch

NASA Balances Water Budget with New Estimates of Liquid Assets

NASA logo.

July 7, 2015

Many pressing questions about Earth’s climate revolve around water. With droughts and flooding an ongoing concern, people want to know how much water is on the move and where it is going. To help answer those questions, a new NASA study provides estimates for the global water cycle budget for the first decade of the 21st century, taking the pulse of the planet and setting a baseline for future comparisons.

The water cycle is the catch-all phrase to describe the movement of water – in its different forms, e.g., liquid, gas and solid – around the planet. It includes freshwater used in households and for agriculture, so any changes to the patterns of where rain and snow occur due to the changing climate may have huge impacts for communities worldwide.

Graphic above: The water cycle describes how water evaporates from Earth’s surface, rises into the atmosphere, cools, condenses to form clouds, and falls again to the surface as precipitation. About 75 percent of the energy (or heat) in the global atmosphere is transferred through the evaporation of water from Earth’s surface. Graphic Credit: NASA.

The study is a rigorous accounting of the movements of Earth’s water from 2000 to 2010, and the first to rely solely on satellite observations and data-integrating models. The new estimates were derived simultaneously with estimates for the amount of energy from the sun available to heat and move water. A hotter day outside means, for example, that more water evaporates from the soil, plants or the ocean, so putting a number on the amount of heat energy helps scientists put a number on the amount of water that lifts into the atmosphere and is then transported by winds around the world. Assessing these two major components of Earth’s climate system is the first step for evaluating how patterns of water and energy may be affected by climate change.

“To document change you need to understand what the current state is – really have a good, sound understanding and quantification of the current state. Then you can tease out changes in the future,” said lead author Matt Rodell, a hydrologist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

The results, published July 7 online in the Journal of Climate, show that each year heat from the sun evaporates 107,841 cubic miles (449,500 cubic kilometers) of water from the world’s oceans. For reference, the Great Lakes in the United States hold about 5,446 cubic miles (22,700 cubic km) of water. On land, 16,938 cubic miles (70,600 cubic km) of water evaporates from soil and plants. The moisture collects as water vapor in the atmosphere, and winds blow it to other parts of the world where it condenses into clouds, rainfall and snowfall.

Graphic above: The amount of water per year that precipitates and evaporates from six ocean basins and three seas. The amounts listed are in units of thousand cubic kilometers. For reference, all yearly human water use is 9.1 thousand cubic km on this scale. Graphic Credits: NASA Goddard/Conceptual Image Lab.

The scientists also calculated that 96,805 cubic miles (403,500 cubic km) of precipitation fall over the ocean each year, an estimate about 5 percent higher than the previous standard estimate, and 27,950 cubic miles (116,500 cubic km) of precipitation fall over land. Of the precipitation over land, 11,012 cubic miles (45,900 cubic km) runs through streams and rivers into the oceans and 16,938 cubic miles (70,600 cubic km) evaporates into the atmosphere. For comparison, each year, all humans on Earth collectively consume for agriculture, industry and water supply 2,182 cubic miles (9,100 cubic km; enough to fill 3 million football stadiums), less than 8 percent of total land precipitation.

In addition to the global and annual numbers, the researchers calculated water cycle estimates for each of seven land masses and nine ocean basins, as well as provided monthly estimates for the globe and each region.

Graphic above: The amount of water per year that precipitates, evaporates, runs off into streams and rivers, or soaks into groundwater storage for each of seven main land masses. The amounts listed are in units of thousand cubic kilometers. For reference, all yearly human water use is 9.1 thousand cubic km on this scale. Graphic Credits: NASA Goddard/Conceptual Image Lab.

These data for the current state of the water cycle will be used to improve how climate models predict the distribution and intensity of rain and snowfall events, said co-author Tristan L’Ecuyer, an atmospheric science professor at the University of Wisconsin at Madison. In climate models, precipitation changes are more difficult to predict than temperature changes because rain and snow involve processes in clouds that take place on the order of miles – scales too small to resolve for most climate models, whose smallest unit is often about the size of Connecticut. Having better estimates of current precipitation rates and how they vary with the seasons is critical to improve the models, said L’Ecuyer.

Scientists combined data from 10 sources that made use of observations from more than 25 satellites to describe different aspects of the water cycle: precipitation and evaporation over land and oceans, atmospheric water vapor and its movement, river runoff, and water storage including groundwater, soil moisture and snowpack.

The goal was then to balance the amount of water that went into each “compartment” of the water cycle, such as the ocean, a continent or a lake, with what came out. Earth is a closed system, which means that any water that evaporates from the surface must be accounted for in the atmospheric water vapor, which must then be accounted for when it condenses into rain or snow, and so on. Each of these stages was described by a different dataset.

Making all the datasets work together was challenging, said Rodell.

“Things don’t always add up because the measurements aren’t perfect,” he said. “It’s like if you’re training for a marathon, and you find a route that Google Maps says is 26.2 miles. Then you run it and your iPhone app says you went 27.0 miles, and then you drive it and your car says you went 26.5 miles. Which one is right? You might guess the accuracy of each measurement and come up with an estimate somewhere in the middle.”

To resolve the differences between datasets, Rodell, L’Ecuyer, and their team came up with a new mathematical technique to get the best estimate. They based it on how accurate experts believe each measurement to be, a number described as the scientific uncertainty or range of possible answers that are still reasonably correct.

It’s as if the water cycle were a jigsaw puzzle, and each dataset for precipitation, water vapor, and so on were individual pieces that have to fit with all the other pieces. However, unlike your traditional jigsaw puzzle, here each piece has a certain amount of wiggle room – its range of possible answers.

As it turned out, the water cycle pieces did fit together within the wiggle room, allowing the team to see the big picture.

“That’s very encouraging,” said L’Ecuyer. “The data sets that we’re generating – even though they are independently generated – they’re all coming up with realistic uncertainty bars that allow us to derive these benchmark estimates.”

The water cycle estimates were calculated in tandem with estimates made for the energy budget, an approach, that while not new, was “very well executed,” said Peter van Oevelen, director, International of the Global Energy and Water Exchanges project of the World Climate Research Programme in Washington, who was not involved in the research.

“The estimates of the various water balance components cannot be done without looking at the energetic components,” he said, adding that work still remained to improve the estimates for certain parts of the water and energy cycles, such as evapotranspiration, the estimates of how much water evaporates from soils and plants.

Rodell agreed, and is looking forward to incorporating data sets from satellites launched since 2010, such as the Soil Moisture Active Passive mission, launched in 2014, that may help refine those estimates.

These water cycle and energy budget datasets are made possible by NASA’s fleet of Earth-observing satellites, which see all parts of the planet, including the oceans, remote areas and developing countries where it’s difficult or impossible for scientists to obtain “on the ground” measurements, said Rodell. The next generation of satellites launched since 2010 will eventually allow estimates of water movement to be produced for the current decade with even higher accuracy, he said.

Read the papers here:

The Observed State of the Water Cycle in the Early 21st Century: http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-14-00555.1

The Observed State of the Energy Budget in the Early 21st Century: http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-14-00556.1

Graphics (mentioned), Text, Credits: NASA's Earth Science News Team/Ellen Gray.

Greetings, Orbiter.ch

New Horizons Map of Pluto: The Whale and the Donut

NASA - New Horizons Mission logo.

July 7, 2015

Image above: This map of Pluto, made from images taken by the LORRI instrument aboard New Horizons, shows a wide array of bright and dark markings of varying sizes and shapes. Perhaps most intriguing is the fact that all of the darkest material on the surface lies along Pluto’s equator. The color version was created from lower-resolution color data from the spacecraft’s Ralph instrument. Image Credits: NASA-JHUAPL-SWRI.

This is the latest map of Pluto created from images taken from June 27 to July 3 by the Long Range Reconnaissance Imager (LORRI) on New Horizons, combined with lower-resolution color data from the spacecraft’s Ralph instrument. The center of the map corresponds to the side of Pluto that will be seen close-up during New Horizons’ July 14 flyby.

This map gives mission scientists an important tool to decipher the complex and intriguing pattern of bright and dark markings on Pluto’s surface. Features from all sides of Pluto can now be seen at a glance and from a consistent perspective, making it much easier to compare their shapes and sizes. 

The elongated dark area informally known as “the whale,” along the equator on the left side of the map, is one of the darkest regions visible to New Horizons. It measures some 1,860 miles (3,000 kilometers) in length.

Directly to the right of the whale’s “head” is the brightest region visible on the planet, which is roughly 990 miles (1,600 kilometers) across. This may be a region where relatively fresh deposits of frost—perhaps including frozen methane, nitrogen and/or carbon monoxide—form a bright coating.

Continuing to the right, along the equator, we see the four mysterious dark spots that have so intrigued the world, each of which is hundreds of miles across. Meanwhile, the whale’s “tail,” at the left end of the dark feature, cradles a bright donut-shaped feature about 200 miles (350 kilometers) across. At first glance it resembles circular features seen elsewhere in the solar system, from impact craters to volcanoes. But scientists are holding off on making any interpretation of this and other features on Pluto until more detailed images are in hand.

Of course, higher-resolution images in the days to come will allow mission scientists to make more accurate maps, but this map is a tantalizing preview.

A Google Earth overlay of New Horizons' latest map of Pluto

“We’re at the ‘man in the moon’ stage of viewing Pluto,” said John Spencer of the Southwest Research Institute, Boulder, Colorado, deputy leader of the Geology, Geophysics and Imaging team. “It’s easy to imagine you’re seeing familiar shapes in this bizarre collection of light and dark features. However, it’s too early to know what these features really are.”

Readers who use Google Earth can download a KMZ version of the map here:
http://pluto.jhuapl.edu/Multimedia/Google-Map/

NASA's New Horizons spacecraft arrives at Pluto on July 14th

Video above: NASA's New Horizons spacecraft arrives at Pluto on July 14th; a journey lasting nearly 10 years and traveling over 3 billion miles. Watch coverage of the historic flyby of Pluto on NASA Television as NASA counts down to the Pluto encounter of a lifetime.
http://www.nasa.gov/multimedia/nasatv/index.html

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft, and manages the mission for NASA's Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

For more information about New Horizons mission, visit: http://www.nasa.gov/mission_pages/newhorizons/main/index.html

Images, Video, Text, Credits: NASA/Tricia Talbert/NASA TV.

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