Here are some pictures. Were they taken in space, or painted here on Earth?

One of the most enduring and inspiring side effects of space exploration is the pictures -- pictures of Earth taken from new heights; pictures of Earth's neighbors, taken from new angles; pictures that resemble, and in fact are, art. They are magical. They are mysterious. They are weird. They suggest, if they don't fully embody, why we go to the trouble of exploring in the first place. 

And they often resemble art of a more earthly variety. Below is a collection of images -- some of them created by prolific space photographer Chris Hadfield, taken from the International Space Station (we'll call those "NASA"), some of them created by nearly-as-prolific painters here on Earth (we'll call those "MOMA"). Here's a game: Can you tell the difference between the two? 

Scroll down for the key.

1. NASA or MOMA?

2. NASA or MOMA?

3. NASA or MOMA?

4. NASA or MOMA?

5. NASA or MOMA?

6. NASA or MOMA?

7. NASA or MOMA?

8. NASA or MOMA?

9. NASA or MOMA?

10. NASA or MOMA?

11. NASA or MOMA?

12. NASA or MOMA?

13. NASA or MOMA?

14. NASA or MOMA?

15. NASA or MOMA?

16. NASA or MOMA?

17. NASA or MOMA?

18. NASA or MOMA?

19. NASA or MOMA?

20. NASA or MOMA?

 

Key:

1. NASA: A patchwork of farms in Central Asia (Via Chris Hadfield)
2. NASA: The Sahara desert (Via Chris Hadfield)
3. NASA: A storm, as seen from space (Via Chris Hadfield)
4. MOMA: Jean-Pierre Vieville, "Les futilités utiles" (Vieville Art Deco)
5. NASA: Rocks in Chile (Via Chris Hadfield)
6. NASA: An African lake (Via Chris Hadfield)
7. NASA: Farms in Saudi Arabia (Via Chris Hadfield)
8. MOMA: Gerhard Richter, "Grau, 898-15, 2006" (Marian Goodman Gallery)
9. MOMA: from Vincent Van Gogh, "Patch of Grass," 1887 (Wikimedia Commons)
10. NASA: Braided rolls of clouds over the Balkans (Via Chris Hadfield)
11. MOMA: Gerhard Richter, Green-Blue, 1993 (Gerhard Richter.com)
12. MOMA: Jean-Pierre Vieville, "Les particules inattendues" (Vieville Art Deco)
13. NASA: A fan of sand in oman (Via Chris Hadfield)
14. NASA: Rocks in Africa (Via Chris Hadfield)
15. MOMA: Jackson Pollock, Number 1, 1950 (Lavender Mist) (National Gallery of Art)
16. MOMA: Cai Guo-Qiang, Corcovado and Fantasia, 2013 (Collection of the artist)
17. NASA: Thunderstorms from above (Via Chris Hadfield)
18. MOMA: from Vincent Van Gogh, "Wheatfield With Crows," 1890 (Wikimedia Commons)
19. MOMA: Gerhard Richter, "15. Nov.06, 898-12," 2006 (Marian Goodman Gallery)
20. NASA: Australia from above (Via Chris Hadfield)

Courtesy of Geospatial Resource Center

A new study using data from a pair of gravity-measuring NASA satellites finds that large parts of the arid Middle East region lost freshwater reserves rapidly during the past decade. 

Scientists at the University of California, NASA's Goddard Space Flight Center and the National Center for Atmospheric Research in Boulder found during a seven-year period beginning in 2003 that parts of Turkey, Syria, Iraq and Iran along the Tigris and Euphrates river basins lost 117 million acre feet (144 cubic kilometers) of total stored freshwater. That is almost the amount of water in the Dead Sea. The researchers attribute about 60 per cent of the loss to pumping of groundwater from underground reservoirs. 

The findings are the result of one of the first comprehensive hydrological assessments of the entire Tigris-Euphrates-Western Iran region. Because obtaining ground-based data in the area is difficult, satellite data, such as those from NASA's twin Gravity Recovery and Climate Experiment (GRACE) satellites, are essential. GRACE is providing a global picture of water storage trends and is invaluable when hydrologic observations are not routinely collected or shared beyond political boundaries. 

"GRACE data show an alarming rate of decrease in total water storage in the Tigris and Euphrates river basins, which currently have the second fastest rate of groundwater storage loss on Earth, after India," said Jay Famiglietti, principal investigator of the study and a hydrologist and professor at UC Irvine. "The rate was especially striking after the 2007 drought. Meanwhile, demand for freshwater continues to rise, and the region does not coordinate its water management because of different interpretations of international laws." 

Famiglietti said GRACE is like having a giant scale in the sky. Within a given region, rising or falling water reserves alter Earth's mass, influencing how strong the local gravitational attraction is. By periodically measuring gravity regionally, GRACE tells us how much each region's water storage changes over time. 

"GRACE really is the only way we can estimate groundwater storage changes from space right now," Famiglietti said. 

The team calculated about one-fifth of the observed water losses resulted from soil drying up and snowpack shrinking, partly in response to the 2007 drought. Loss of surface water from lakes and reservoirs accounted for about another fifth of the losses. The majority of the water lost -- approximately 73 million acre feet (90 cubic kilometers) -- was due to reductions in groundwater. 

"That's enough water to meet the needs of tens of millions to more than a hundred million people in the region each year, depending on regional water use standards and availability," said Famiglietti. 

Famiglietti said when a drought reduces an available surface water supply, irrigators and other water users turn to groundwater supplies. For example, the Iraqi government drilled about 1,000 wells in response to the 2007 drought, a number that does not include the numerous private wells landowners also very likely drilled. 

"Water management is a complex issue in the Middle East -- an area that already is dealing with limited water resources and competing stakeholders," said Kate Voss, lead author of the study and a water policy fellow with the University of California's Center for Hydrological Modeling in Irvine, which Famiglietti directs. 

"The Middle East just does not have that much water to begin with, and it's a part of the world that will be experiencing less rainfall with climate change," said Famiglietti. "Those dry areas are getting dryer. The Middle East and the world's other arid regions need to manage available water resources as best they can." 

Courtesy of Gizmodo

The $496 million Gravity Recovery and Interior Laboratory (GRAIL) is part of the NASA Discovery Program, and aims to determine the moon's interior structure via fluctuations in its gravitational field as well as to uncover potential clues about the formation of our solar system's rocky inner planets. See, mascons—MASs CONcentrations—are "positive gravitational anomalies" typically found in impact craters all over the moon, and are thought to be caused by basaltic lava flows collecting in these craters. These pockets of extra density can greatly affect the orbits of passing spacecraft over time, as well as efforts to "slingshot" craft into the outer solar system.

To see what's going on under the moon's surface, NASA launched a pair of orbiters, dubbed GRAIL A (Ebb) and GRAIL B (Flow), from Cape Canaveral Air Force Station, Florida, aboard a Delta II in September of 2011. The pair arrived at the moon 24 hours apart, on New Year's Eve 2011 and New Year's Day 2012. The spacecraft took their time reaching the moon (three weeks as opposed to the normal three days) in order to conserve their hydrazine fuel and reduce their lunar approach speed, which aided in achieving their super-low 50 km orbit heights.

Each spacecraft is outfitted with a Lunar Gravity Ranging System, the same system used to precisely map the Earth's gravitational field during the GRACE mission, which uses Ka-band radar to collect measurements. As the spacecraft fly over gravitational fields of varying intensity, the LGRS measures the change in their relative positions and velocities with a precision of a few microns—about the diameter of a red blood cell. In addition to the LGRS, each craft is also equipped with a set of joystick-controlled cameras as part of the MoonKAM project (Moon Knowledge Acquired by Middle school students—MoonKAM), which allow school children to directly control the orbiters' digital eyes. [Wikipedia - NASA 1, 2 - LA Times]

NASA UAVSAR image of the Deepwater Horizon oil spill, collected June 23, 2010. The oil appears much darker than the surrounding seawater in the greyscale image. This is because the oil smoothes the sea surface and reduces its electrical conductivity, causing less radar energy to bounce back to the UAVSAR antenna. Additional processing of the data by the UAVSAR team produced the two inset color images, which reveal the variability of the oil spill's characteristics, from thicker, concentrated emulsions (shown in reds and yellows) to minimal oil contamination (shown in greens and blues). Dark blues correspond to areas of clear seawater bordering the oil slick. Images credit: NASA/JPL-Caltech 

Researchers at NASA's Jet Propulsion Laboratory and the California Institute of Technology in Pasadena have developed a method to use a specialized NASA 3-D imaging radar to characterize the oil in oil spills, such as the 2010 BP Deepwater Horizon spill in the Gulf of Mexico. The research can be used to improve response operations during future marine oil spills. 

Caltech graduate student Brent Minchew and JPL researchers Cathleen Jones and Ben Holt analyzed NASA radar imagery collected over the main slick of the BP Deepwater Horizon oil spill on June 22 and June 23, 2010. The data were acquired by the JPL-developed Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) during the first of its three deployments over the spill area between June 2010 and July 2012. The UAVSAR was carried in a pod mounted beneath a NASA C-20A piloted aircraft, a version of the Gulfstream III business jet, based at NASA's Dryden Aircraft Operations Facility in Palmdale, Calif. The researchers demonstrated, for the first time, that a radar system like UAVSAR can be used to characterize the oil within a slick, distinguishing very thin films like oil sheen from more damaging thick oil emulsions. 

"Our research demonstrates the tremendous potential of UAVSAR to automate the classification of oil in a slick and mitigate the effects of future oil spill tragedies," said Jones. "Such information can help spill incidence response commanders direct cleanup operations, such as the mechanical recovery of oil, to the areas of thick oil that would have the most damaging environmental impacts." 

Current visual oil classification techniques are qualitative, and depend upon the skill of the people doing the assessment and the availability of skilled observers during an emergency. Remote sensing allows larger areas to be covered in a consistent manner in a shorter amount of time. Radar can be used at night or in other low-light or poor weather conditions when visual surveys can't be conducted. 

Radar had previously been used to detect the extent of oil slicks, but not to characterize the oil within them. It had generally been assumed that radar had little to no use for this purpose. The team demonstrated that UAVSAR could be used to identify areas where thick oil had mixed with the surface seawater to form emulsions, which are mixtures of oil and seawater. 

Identifying the type of oil in a spill is vital for assessing its potential harm and targeting response efforts. For example, thin oil consists of sheens that measure from less than 0.0002 inches (0.005 millimeters) to about 0.002 inches (0.05 millimeters) thick. Sheens generally form when little oil is released, as in the initial stages of a spill, or from lightweight, volatile components of spill material. Because sheens contain little oil volume, they weather and evaporate quickly, and are of minor concern from an environmental standpoint. Oil emulsions, on the other hand, are 0.04 inches (1 millimeter) thick, contain more oil, and persist on the ocean surface for much longer, thereby potentially having a greater environmental impact in the open sea and along the shoreline. 

"Knowing the type of oil tells us a lot about the thickness of the oil in that area," said Jones. 

The researchers acquired data in June 2010 along more than 3,400 miles (5,500 kilometers) of flight lines over an area of more than 46,330 square miles (120,000 square kilometers), primarily along the Gulf Coast. They found that at the time the slick was imaged by UAVSAR, much of the surface layer of the Deepwater Horizon spill's main slick consisted of thick oil emulsions. 

UAVSAR characterizes an oil spill by detecting variations in the roughness of its surface and, for thick slicks, changes in the electrical conductivity of its surface layer. Just as an airport runway looks smooth compared to surrounding fields, UAVSAR "sees" an oil spill at sea as a smoother (radar-dark) area against the rougher (radar-bright) ocean surface because most of the radar energy that hits the smoother surface is deflected away from the radar antenna. UAVSAR's high sensitivity and other capabilities enabled the team to separate thick and thin oil for the first time using a radar system. 

"We knew we were going to detect the extent of the spill," said Holt. "But we had this great new instrument, so we wanted to see how it would work in this extreme situation, and it turned out to be really unique and valuable, beyond all previous radar results for spills." 

"We studied an unprecedented event using data collected by a sophisticated instrument and were able to show that there was a lot more information contained in the data than was apparent when we began," said Minchew. "This is a good example of how the tools of science could be used to help mitigate disasters in real time." 

UAVSAR is returning to the Gulf of Mexico area this month and will image the area around the Deepwater Horizon site to look for leaks. In the future, UAVSAR data may be combined with imaging spectroscopic data from JPL's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) instrument to further improve the ability to characterize oil spills under a broader range of environmental conditions. 

In addition to characterizing the oil slick, UAVSAR imaged most of the U.S. Gulf of Mexico coastline, extending from the Florida Keys to Corpus Christi, Texas, with extensive inland coverage of the southern Louisiana wetlands around Barataria Bay, the terrestrial ecosystem that ultimately sustained the greatest oiling from the massive spill. Researchers tracked the movement of the oil into coastal waterways and marshlands, monitored impact and recovery of oil-affected wetlands, and assessed how UAVSAR can support emergency responders in future disasters. 

UAVSAR is also used to detect detailed Earth movements related to earthquakes, volcanoes and glaciers, as well as for soil moisture and forestry biomass studies. For more on UAVSAR, see:http://uavsar.jpl.nasa.gov/mission_flights.html . 

Results of this study are published this month in the Institute of Electrical and Electronics Engineers journal Transactions on Geoscience and Remote Sensing. Caltech manages JPL for NASA.