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Inexpensive Chinese solar panels are pitting Americans who want cheap equipment against those who want to make it

Space telescopes detect on average one gamma-ray burst per day, adding to thousands of bursts detected throughout the years, and a community of volunteers are making research into these bursts possible.

The private ADRAS-J probe snapped an epic, up-close image of its rendezvous target, a Japanese rocket stage that's been circling Earth since 2009.

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Preparations for Next Moonwalk Simulations Underway (and Underwater) The Colorado River supplies water to more than 40 million people as it snakes through seven U.S. states, including the part of southeastern Utah seen in this photo snapped by an astronaut aboard the International Space Station. The Colorado basin was identified in a NASA-led study as a region experiencing intense human water use.NASA

The novel approach to estimating river water storage and discharge also identifies regions marked by ‘fingerprints’ of intense water use.

A study led by NASA researchers provides new estimates of how much water courses through Earth’s rivers, the rates at which it’s flowing into the ocean, and how much both of those figures have fluctuated over time — crucial information for understanding the planet’s water cycle and managing its freshwater supplies. The results also highlight regions depleted by heavy water use, including the Colorado River basin in the United States, the Amazon basin in South America, and the Orange River basin in southern Africa.

For the study, which was recently published in Nature Geoscience, researchers at NASA’s Jet Propulsion Laboratory in Southern California used a novel methodology that combines stream-gauge measurements with computer models of about 3 million river segments around the world.

A NASA-led study combined stream-gauge measurements with computer models of 3 million river segments to create a global picture of how much water Earth’s rivers hold. It estimated that the Amazon basin contains about 38% of the world’s river water, the most of any hydrological region evaluated. NASA

The scientists estimate that the total volume of water in Earth’s rivers on average from 1980 to 2009 was 539 cubic miles (2,246 cubic kilometers). That’s equivalent to half of Lake Michigan’s water and about 0.006% of all fresh water, which itself is 2.5% of the global volume. Despite their small proportion of all the planet’s water, rivers have been vital to humans since the earliest civilizations.

Although researchers have made numerous estimates over the years of how much water flows from rivers into the ocean, estimates of the volume of water rivers collectively hold — known as storage — have been few and more uncertain, said JPL’s Cédric David, a co-author of the study.

He likened the situation to spending from a checking account without knowing the balance. “We don’t know how much water is in the account, and population growth and climate change are further complicating matters,” David said. “There are many things we can do to manage how we’re using it and make sure there is enough water for everyone, but the first question is: How much water is there? That’s fundamental to everything else.”

The NASA-led study estimated flow through 3 million river segments, identifying locations around the world marked by intense human water use, including parts of the Colorado, Amazon, Orange, and Murray-Darling river basins, shown as gray here. NASA

Estimates in the paper could eventually be compared with data from the international Surface Water and Ocean Topography (SWOT) satellite to improve measurements of human impacts on Earth’s water cycle. Launched in December 2022, SWOT is mapping the elevation of water around the globe, and changes in river height offer a way to quantify storage and discharge.

‘Fingerprints’ of Water Use

The study identified the Amazon basin as the region with the most river storage, holding about 204 cubic miles (850 cubic kilometers) of water — roughly 38% of the global estimate. The same basin also discharges the most water to the ocean: 1,629 cubic miles (6,789 cubic kilometers) per year. That’s 18% of the global discharge to the ocean, which averaged 8,975 cubic miles (37,411 cubic kilometers) per year from 1980 to 2009.

Although it’s not possible for a river to have negative discharge — the study’s approach doesn’t allow for upstream flow — for the sake of accounting, it is possible for less water to come out of some river segments than went in. That’s what the researchers found for parts of the Colorado, Amazon, and Orange river basins, as well as the Murray-Darling basin in southeastern Australia. These negative flows mostly indicate intense human water use.

“These are locations where we’re seeing fingerprints of water management,” said lead author Elyssa Collins, who conducted the analysis as a JPL intern and doctoral student at North Carolina State University in Raleigh.

A New Way to Quantify Rivers

For decades, most estimates of Earth’s total river water were refinements of a 1974 United Nations figure, and no study has illustrated how the amount has varied with time. Better estimates have been hard to come by, David said, due to a lack of observations of the world’s rivers, particularly those far from human populations.

Another issue has been that there are many more stream gauges monitoring the levels and flow of large rivers than there are of small ones. There’s also broad uncertainty in estimates of land runoff — the rainwater and snowmelt that flow into rivers.

The new study started from the premise that runoff flowing into and through a river system should roughly equal the amount that gauges measure downstream. Where the researchers found inconsistencies between simulated runoff from three land surface models and gauge measurements taken from approximately 1,000 locations, they used the gauge measurements to correct the simulated runoff numbers.

Then they modeled the runoff through rivers on a high-resolution global map developed using land-elevation data and imagery from space, including from NASA’s Shuttle Radar Topography Mission. This approach yielded discharge rates, which were used to estimate average and monthly storage for individual rivers and the planet’s rivers in total. 

Using a consistent methodology enables comparisons in flow and human drawdown between different regions. 

“That way we can see where in the world the most amount of river water is stored, or where the most amount of water is being emptied into oceans from rivers,” said Collins, now a postdoctoral researcher at the University of North Carolina at Chapel Hill.

News Media Contacts

Andrew Wang / Jane J. Lee
Jet Propulsion Laboratory, Pasadena, Calif.
626-379-6874 / 818-354-0307
andrew.wang@jpl.nasa.gov / jane.j.lee@jpl.nasa.gov

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Details Last Updated Apr 26, 2024 Related Terms

• SWOT (Surface Water and Ocean Topography)
• Earth
• Earth Science
• Earth Science Division
• Water on Earth

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The magnificent central bar of NGC 2217 (also known as AM 0619-271) shines bright in the constellation of Canis Major (The Greater Dog), in this image taken by the NASA/ESA Hubble Space Telescope. Roughly 65 million light-years from Earth, this barred spiral galaxy is a similar size to our Milky Way at 100,000 light-years across.

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This NASA/ESA Hubble Space Telescope images showcases the galaxy NGC 2217.ESA/Hubble & NASA, J. Dalcanton; Acknowledgement: Judy Schmidt (Geckzilla)

The magnificent central bar of NGC 2217 (also known as AM 0619-271) shines bright in the constellation of Canis Major (The Greater Dog), in this image taken by the NASA/ESA Hubble Space Telescope. Roughly 65 million light-years from Earth, this barred spiral galaxy is a similar size to our Milky Way at 100,000 light-years across. Many stars are concentrated in its central region forming the luminous bar, surrounded by a set of tightly wound spiral arms.

The central bar in these types of galaxies plays an important role in their evolution, helping to funnel gas from the disk into the middle of the galaxy. The transported gas and dust are then either formed into new stars or fed to the supermassive black hole at the galaxy’s center. Weighing from a few hundred to over a billion times the mass of our Sun, supermassive black holes are present in almost all large galaxies.

This image was colorized with data from the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS).

Text credit: European Space Agency (ESA)

Media Contact:

Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, MD
claire.andreoli@nasa.gov

Identification of Noise Sources During Launch Using Phased Array Microphone Systems 

Every part of a launch vehicle, launch pad, and ground operation equipment is subjected to the high acoustic load generated during lift-off [1]. Therefore, many extreme measures are taken to try to suppress this acoustic environment by damping with a water deluge system and diverting engine plumes away from the vehicle via flame trenches. Even single decibel reductions of the acoustic levels can translate into a sizable reduction of acoustic loadings, certification needs, operational costs, and even vehicle weight. Therefore, lowering the acoustic level via various mitigation schemes is an important aspect of a launch pad design.   

In 2011 and 2012, the NESC sponsored research into the effectiveness of a microphone phased array (MPA) to identify noise sources and tested the array during an Antares launch from the Wallops Flight Facility [2]. This simple prototype array was able to identify impingement-related noise sources during the launch.  

Today, building on this previous work, a new open-space truss MPA architecture is in development and test for use during the Artemis II launch. This truss structure consists of an aluminum tubular frame holding 70 microphones mounted in optimized positions over a dome-shaped surface (Figure 1). The center canister structure holds visible and infrared cameras as well as the amplifier electronics that transfer and relay microphone signals out to data cables that send information to the ground-mounted data acquisition system. The collected data are postprocessed using a functional-orthogonal beamforming routine that minimizes the effects of side lobes and reflections on the acoustic signal [3]. This produces a much cleaner image of primary noise impingement sources emanating from the vehicle and launch pad structures. 

Figure 1. Overall view of the MPA, cable bundle, and data acquisition cabinet.  

The NESC activity is performing verification and validation tests to determine the MPA’s environmental survivability and validate the beamforming capability. This is being done using a phased testing approach. Phase 1 testing performed at ARC elevated the MPA (Figure 2) and used horns and speakers of known intensity to ensure its ability to identify and separate noise sources (Figure 3). 

Figure 2. Setup for the outdoor test using a train horn and a long-range acoustic device (LRAD) speaker. The MPA was raised to test heights by a Telehandler.  Figure 3. Comparison between different beamform schemes at a fixed f=1338 Hz with array center 100 ft. horizontal and 10 ft. above LRAD speaker. 

In phase 2, the system was subjected to an actual engine noise environment during a static fire test at SSC. The MPA viewed the A-1 engine test stand during an RS-25 engine test from 460 feet, a similar distance from KSC Pad 39B to the lightning tower, where the MPA will be mounted for Artemis II (Figure 4). Results successfully identified and pinpointed the transient engine acoustic sources during the test (Figure 5). 

Figure 4. Scaffold system used to mount MPA and location of the array with respect to the SSC A-1 test stand. Right Image Credit: Google Maps  Noise sources identified at the indicated third-octave center frequencies using functional-orthogonal beamform.

The final test occurred during the NG-19 Antares launch from the Wallops Flight Facility in July 2023. The MPA tracked the plume and acoustic environment during the launch, showing transition from initial engine thrust to the overpressure environment flowing from the flame trench as the vehicle lifted off (Figure 6). The array was able to collect meaningful data while mounted outside, under acoustic conditions similar to those expected during the Artemis II launch and also subjected to heat, humidity, salt air, and extreme weather. 

Figure 6. Time evolution of noise source generation during the NG-19 launch. The acoustic intensity of the redirected flow from the flame trench opening evolves to become a much stronger noise source, while acoustics from the plume are effectively mitigated by the sound suppression on the launch pad surface.  

Next, the MPA will be deployed at KSC for the Artemis II launch to measure the acoustic impingement and identify critical noise sources during that event. The data collected will help further refine and optimize the sound suppression systems for Artemis III and future launches. 

References: 

1. Eldred, K. M. & Jones, G. W., Jr., “Acoustic load generated by the propulsion system,” NASA SP-8072, 1971. 

2. Panda, J., Mosher, R. N. & Porter, B. J., “Noise Source Identification During Rocket Engine Test Firings and a Rocket Launch,” Journal of Spacecraft and Rockets,   Vol. 51, No. 4, July-Aug 2014. DOI: 10.2514/1.A32863 

3. Dougherty, R.P., “Functional Beamforming for Aeroacoustic Source Distributions,” 20th AIAA/CEAS Aeroacoustics Conference, 10.2514/6.2014-3066, 2014. 

For more information, contact:  

Dr. Jayanta Panda jayanta.panda-1@nasa.gov 

Kenneth R. Hamm, Jr. kenneth.r.hamm@nasa.gov 

Joel W. Sills joel.w.sills@nasa.gov 

To celebrate the launch of our new event series in the US, kicking off with a masterclass on the brain and consciousness, we have unlocked five incredible long reads

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Seasonal spider-like features were spotted sprouting up through surface cracks near Mars’ Inca City region.

The genetic variant, which causes people to be insensitive to growth hormone, may also protect people from heart disease

The genetic variant, which causes people to be insensitive to growth hormone, may also protect people from heart disease

Researchers might have located the birthplace of 469219 Kamo‘oalewa, a small asteroid that has been described as Earth’s “mini-moon.”

The post Earth’s Mini-Moon Linked to Farside Lunar Crater appeared first on Sky & Telescope.

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Preparations for Next Moonwalk Simulations Underway (and Underwater) Julia Chavez examines an experiment within an oxygen-free chamber at NASA’s Jet Propulsion Laboratory in March. Chavez is one of several students from California State University, Los Angeles who are interning at JPL’s Origins and Habitability Lab.NASA/JPL-Caltech Cathy Trejo (right) shows off a tube filled with pebbles designed to mimic Martian regolith. During experiments, fluid is flushed through the tube many times, giving JPL astrobiology interns like Trejo and Julia Chaves (left) the chance to study how chemicals may have interacted with water on Mars billions of years ago.NASA/JPL-Caltech

At the agency’s Jet Propulsion Laboratory, interns from Cal State LA are learning key skills studying the origins of life.

What does wastewater management in Los Angeles have to do with the search for life on Mars? Eduardo Martinez certainly didn’t make the connection when he was pursuing a master’s in civil engineering. Not at first. Then his professor pointed him toward an internship opportunity at NASA’s Jet Propulsion Laboratory for astrobiology, the study of life’s origins and the possibility of life beyond Earth.

That professor, Arezoo Khodayari of California State University, Los Angeles, helped Martinez understand the chemistry common to both fields. Soon, Martinez saw that just as phosphorous, nitrogen, and other chemicals in wastewater can fuel algal blooms in the ocean, they can potentially provide energy for microbial life on other planets.

Interns working in JPL’s Origins and Habitability Lab grow fingerlike mineral structures like the one shown here to simulate oceans on early Earth — and possibly other planets. By studying how these structures form in the lab, scientists hope to learn more about potential life-creating chemical reactions. NASA/JPL-Caltech

“Once I got a taste of planetary science, I knew I needed more,” said Martinez, who did the internship while finishing his degree at Cal State LA, where more than 70% of students are Latino and few have historically participated in NASA research. “If not for JPL, I would have stopped with my master’s.” Now he’s pursuing a doctorate in geosciences at the University of Nevada, Las Vegas.

The inspiration that connects both fields lies at the core of a new NASA grant. Khodayari and Laurie Barge, who runs JPL’s Origins and Habitability Laboratory, have received funding for up to six paid JPL internships over two years. The intent is to help develop the next generation of space-minded scientists from the students at Cal State LA.

The grant — one of 11 recently awarded to emerging research universities by NASA’s Science Mission Directorate Bridge Program — helps underrepresented students learn more about astrobiology and perform NASA-sponsored research.

“As a large employer in Southern California, we have a duty to invest in our local communities,” Barge said of JPL’s role in the effort. “It makes NASA and its science more accessible to everyone.”

JPL’s Laurie Barge (far right) and California State University, Los Angeles’ Arezoo Khodayari (second from left) have collaborated for 10 years to bring interns to Barge’s astrobiology lab. JPL’s Jessica Weber (second from right) is also an astrobiologist in the lab; Julia Chavez (far left) and Cathy Trejo (center) are interns.NASA/JPL-Caltech Building Community

Barge and Khodayari have been informally collaborating for 10 years, designing experiments to try to answer questions in their respective fields. Of the four Cal State LA interns Barge has hosted so far, two — including Martinez — have been lead authors on published research papers.

“It is a great accomplishment to publish in a prestigious, peer-reviewed journal, especially as the first author,” Khodayari said. “It’s inspiring to see students from Cal State LA, which is primarily a teaching institution, provided research opportunities that result in these kinds of journal publications.”

She notes that many of her students work multiple jobs, so a paid internship means they can focus entirely on their studies without sacrificing essential income. And, Khodayari added, “they get exposure to a field far from their reality.”

Tools and Skills

In Barge’s lab, dark, fingerlike mineral structures grow in beakers of cloudy liquid meant to simulate oceans on early Earth — and possibly on other planets. By studying how these structures form in the lab, scientists like Barge hope to learn more about the potential life-creating chemical reactions that take place around similar structures, called chimneys, that develop on the ocean floor around hydrothermal vents.

“We learned so much in Laurie’s lab,” said Erika Flores, Barge’s first Cal State LA intern. “Not only are you working independently on your own projects, you’re collaborating with other interns and even other divisions at JPL.”

The middle of five children, Flores was the first in her family to graduate from high school. She initially attended University of California, Berkeley but felt isolated. After returning home, she earned her bachelor’s degree and began studying with Khodayari at Cal State LA.

Although she decided not to become a planetary scientist – “I considered it, but I didn’t want to spend another five years on a Ph.D.; I was ready to get a job” – Flores credits the JPL internship with helping her overcome a case of impostor syndrome. Equipped with a master’s that she completed during her internship, she now works for the Los Angeles County Sanitation Districts, overseeing 13 pumping plants that route wastewater to treatment plants.

Interplanetary Connections

Like Flores, current Cal State LA intern Cathy Trejo wants to improve the world through clean water. She’s studying to be an environmental engineer, with a focus beyond wastewater.

But she was excited to see the parallels between Earth-bound science and planetary science during her internship. Learning to use mass spectrometers has even inspired her. NASA’s Curiosity Mars rover has a mass spectrometer, the Sample Analysis at Mars instrument, that measures the composition of different gases.

“Understanding the instruments we use on Mars has helped me better understand how we study chemistry here on Earth,” Trejo said.

She is fascinated that cumbersome lab instruments can be miniaturized to be taken to other planets, and that scientists are beginning to miniaturize similar instruments that could identify pollutants at Superfund sites.

Barge isn’t giving up hope that Trejo will stick with planetary science, but she’s just happy to help a budding scientist develop. “I hope these student research opportunities offer an appreciation for planetary exploration and how our work at NASA relates to important questions in other fields,” she said.

News Media Contacts

Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433
andrew.c.good@jpl.nasa.gov

Karen Fox / Alise Fisher
NASA Headquarters, Washington
301-286-6284 / 202 358-2546
karen.c.fox@nasa.gov / alise.m.fisher@nasa.gov

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Details Last Updated Apr 26, 2024 Related Terms

• Astrobiology
• Internships

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A strategy for transferring spacecraft trajectories between flight mechanics tools, called Trajectory Reverse Engineering (TRE), has been developed[1]. This innovative technique has been designed to be generic, enabling its application between any pair of tools, and to be resilient to the differences found in the dynamical and numerical models unique to each tool. The TRE technique was developed as part of the NESC study, Flight Mechanics Analysis Tools Interoperability and Component Sharing, to develop interfaces to support interoperability between several of NASA’s institutional flight mechanics tools.  

The development of space missions involves multiple design tools, requiring the transfer of trajectories between them—a task that demands a large amount of trajectory data such as frames, states, state and time parametrizations, and dynamical and numerical models. This is a tedious and time-consuming task that is not always effective, particularly on complex dynamics where small variations in the models can cause trajectories to diverge in the reconstruction process.   

The TRE strategy is a trajectory-sharing process that is agnostic to the models used and performed through a common object: the spacecraft and planet kernels (SPK), developed at JPL Navigation and Ancillary Information Facility. The use of this common object aims to lay the groundwork for a global flight mechanics tool interoperability system (Figure 1). 

Figure 1. A) Interoperability between flight mechanics tools using standardized trajectory structures. B) Traditional specific tool-to-tool interface design.  

An SPK file serves as a container object, representing a trajectory as a 6D invariant structure in phase-space, agnostic to gravitational environments, fidelity models, or numerical representation of the system. A judicious kernel scan is used to recover the trajectory in any new tool, with the minimum (or no) information from the generating source. Impulsive maneuvers can be extracted in the form of velocity discontinuities, finite burns can be detected as variations on the energy of the system, and natural bodies conforming the trajectory universe can be directly read from the kernel.  

States or control points are found at predetermined time intervals or strategic points along the trajectory (e.g., periapsis, apoapsis, flybys closest approach), which are then used to reconstruct the trajectory timeline. The trajectory can be propagated forward in time using the selected set of control points. Due to the discrepancy between tool models, small or large discontinuities might appear between the integrated legs, which can be smoothed by the implementation of a multiple-shooting algorithm (Figure 2).  

Figure 2. Multiple-shooting algorithm, utilizing strategic control points and a forward-backward propagation scheme. 

The TRE strategy was successfully implemented for Monte and Copernicus in the form of Python scripts (examples of reconstructed trajectories from SPK for each of these tools are shown in Figure 3). Through an optional user input file, a user can configure their specific problem. User-defined constraints are also possible, but their implementation would depend on the specific tool. The benefits of this effort include cost reduction through the sharing of capabilities, acceleration of the turnaround process involving various analysis tools at different stages of mission development, improved design solutions through multi-tool mission designs, and a reduction in development redundancy. 

Reference: 

1. Restrepo, R. L., “Trajectory Reverse Engineering: A General Strategy for Transferring Trajectories Between Flight Mechanics Tools” AAS 23-312, January 2023. 

Figure 3. Future and flown missions reconstructions using Copernicus (Europa Clipper, Cassini) and Monte (HLS, Voyager 2) from SPK obtained from the Horizons System database at https://ssd.jpl.nasa.gov/horizons/. 

For information, contact Heather Koehler heather.koehler@nasa.gov and Ricardo L. Restrepo ricardo.l.restrepo@jpl.nasa.gov. 

This is the way to celebrate Star Wars Day in style, with the 6187-piece Lego Ultimate Collector Series Razor Crest, now $130 off

When alpacas mate, males deposit sperm directly into the uterus, a reproductive strategy not confirmed in any other mammals

When alpacas mate, males deposit sperm directly into the uterus, a reproductive strategy not confirmed in any other mammals