Tag: Space News

Living with a Star: NASA and Partners Survey Space Weather Science

infographic describing Geomagnetically Induced Currents, or GICs
Geomagnetically Induced Currents, or GICs, can result from geomagnetic storms — a type of space weather event in which Earth’s magnetic field is rattled by incoming magnetic solar material. The quick-changing magnetic fields create GICs through a process called electromagnetic induction. GICs can flow through railroad tracks, underground pipelines and power grids.
Credits: NASA
NASA has long been a leader in understanding the science of space weather, including research into the potential for induced electrical currents to disrupt our power systems. Last year, NASA scientists worked with scientists and engineers from research institutions and industry during a pair of intensive week-long workshops in order to assess the state of science surrounding this type of space weather. This summary was published Jan. 30, 2017, in the journal Space Weather.

Storms from the sun can affect our power grids, railway systems, and underground pipelines through a phenomenon called geomagnetically induced currents, or GICs. The sun regularly releases a constant stream of magnetic solar material called the solar wind, along with occasional huge clouds of solar material called coronal mass ejections. This material interacts with Earth’s magnetic field, causing temporary changes. That temporary change to the magnetic field can create electric currents just under Earth’s surface. These are GICs.

Long, thin, metal structures near Earth’s surface — such as underground pipelines, railroads and power lines — can act as giant wires for these currents, causing electricity to flow long distances underground. This electric current can cause problems for all three structures, and it’s especially difficult to manage in power systems, where controlling the amount of electric current is key for keeping the lights on. Under extreme conditions, GICs can cause temporary blackouts, which means that studying space weather is a crucial component for emergency management.

“We already had a pretty good grasp of the key moving pieces that can affect power systems,” said Antti Pulkkinen, a space weather researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “But this was the first we had solar experts, heliospheric scientists, magnetospheric physicists, power engineers and emergency management officials all in a room together.”

Though GICs can primarily cause problems for power systems, railroads and pipelines aren’t immune.

“Researchers have found a positive correlation between geomagnetic storms and mis-operation of railway signaling systems,” said Pulkkinen, who is also a member of the space weather research-focused Community Coordinated Modeling Center based at Goddard.

This is because railway signals, which typically control traffic at junctures between tracks or at intersections with roads, operate on an automated closed/open circuit system. If a train’s metal wheels are on the track near the signal, they close the electrical circuit, allowing electrical current to flow to the signal and turn it on.

“Geomagnetically induced currents could close that loop and make the system signal that there’s a train when there isn’t,” said Pulkkinen.

Similarly, current flowing in oil pipelines could create false alarms, prompting operators to inspect pipelines that aren’t damaged or malfunctioning.

In power systems, the GICs from a strong space weather event can cause something called voltage collapse. Voltage collapse is a temporary state in which the voltage of a segment of a power system goes to zero. Because voltage is required for current to flow, voltage collapse can cause blackouts in affected areas.

Though blackouts caused by voltage collapse can have huge effects on transportation, healthcare, and commerce, GICs are unlikely to cause permanent damage to large sections of power systems.

“For permanent transformer damage to occur, there needs to be sustained levels of GICs going through the transformer,” said Pulkkinen. “We know that’s not how GICs work. GICs tend to be much more noisy and short-lived, so widespread physical damage of transformers is unlikely even during major storms.”

The scientists who worked on the survey, part of the NASA Living With a Star Institute, also created a list of the key unanswered questions in GIC science, mostly related to computer modeling and prediction. The group members’ previous work on GIC science and preparedness has already been used to shape new standards for power companies to guard against blackouts. In September 2016, the Federal Energy Regulatory Commission, or FERC, released new standards that require power companies to assess and prepare for potential GIC disruptions.

“We’re really proud that our team members made major contributions to the updated FERC standards,” said Pulkkinen. “It also shows that the U.S. is actively working to address GIC risk.”

Related:

Banner image: Composite image of a coronal mass ejection as seen by the Solar and Heliospheric Observatory. 

Editor: Rob Garner

Photo Credit:  ESA and NASA/SOHO

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NASA to Reveal New Discoveries in News Conference on Oceans Beyond Earth

NASA will discuss new results about ocean worlds in our solar system from the agency’s Cassini spacecraft and the Hubble Space Telescope during a news briefing 2 p.m. EDT on Thursday, April 13. The event, to be held at the James Webb Auditorium at NASA Headquarters in Washington, will include remote participation from experts across the country.

The briefing will be broadcast live on NASA Television and the agency’s website.

These new discoveries will help inform future ocean world exploration — including NASA’s upcoming Europa Clipper mission planned for launch in the 2020s — and the broader search for life beyond Earth.

The news briefing participants will be:

  • Thomas Zurbuchen, associate administrator, Science Mission Directorate at NASA Headquarters in Washington
  • Jim Green, director, Planetary Science Division at NASA Headquarters
  • Mary Voytek, astrobiology senior scientist at NASA Headquarters
  • Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California
  • Hunter Waite, Cassini Ion and Neutral Mass Spectrometer team lead at the Southwest Research Institute (SwRI) in San Antonio
  • Chris Glein, Cassini INMS team associate at SwRI
  • William Sparks, astronomer with the Space Telescope Science Institute in Baltimore

A question-and-answer session will take place during the event with reporters on site and by phone. Members of the public also can ask questions during the briefing using #AskNASA.

To participate by phone, reporters must contact Dwayne Brown at 202-358-1726 or dwayne.c.brown@nasa.gov and provide their media affiliation no later than noon April 13.

For NASA TV downlink information, schedules and to view the news briefing, visit:

http://www.nasa.gov/nasatv

For more information on ocean worlds, visit:

https://www.nasa.gov/specials/ocean-worlds

For more information on Cassini, visit:

https://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

For more information on Hubble, visit:

https://www.nasa.gov/hubble

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Felicia Chou/ Dwayne Brown
Headquarters, Washington
202 358 0257 / 202-358-1077
felicia.chou@nasa.gov / dwayne.c.brown@nasa.gov

Preston Dyches
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-7013
preston.dyches@jpl.nasa.gov

Rob Gutro
Goddard Space Flight Center, Greenbelt, Md.
301-286-4044
robert.j.gutro@nasa.gov

Editor: Katherine Brown

Photo Credit: NASA

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NASA’s Cassini Mission Prepares for ‘Grand Finale’ at Saturn

NASA’s Cassini spacecraft, in orbit around Saturn since 2004, is about to begin the final chapter of its remarkable story. On Wednesday, April 26, the spacecraft will make the first in a series of dives through the 1,500-mile-wide (2,400-kilometer) gap between Saturn and its rings as part of the mission’s grand finale.

“No spacecraft has ever gone through the unique region that we’ll attempt to boldly cross 22 times,” said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. “What we learn from Cassini’s daring final orbits will further our understanding of how giant planets, and planetary systems everywhere, form and evolve. This is truly discovery in action to the very end.”

During its time at Saturn, Cassini has made numerous dramatic discoveries, including a global ocean that showed indications of hydrothermal activity within the icy moon Enceladus, and liquid methane seas on its moon Titan.

Now 20 years since launching from Earth, and after 13 years orbiting the ringed planet, Cassini is running low on fuel. In 2010, NASA decided to end the mission with a purposeful plunge into Saturn this year in order to protect and preserve the planet’s moons for future exploration – especially the potentially habitable Enceladus.

But the beginning of the end for Cassini is, in many ways, like a whole new mission. Using expertise gained over the mission’s many years, Cassini engineers designed a flight plan that will maximize the scientific value of sending the spacecraft toward its fateful plunge into the planet on Sept. 15. As it ticks off its terminal orbits during the next five months, the mission will rack up an impressive list of scientific achievements.

“This planned conclusion for Cassini’s journey was far and away the preferred choice for the mission’s scientists,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. “Cassini will make some of its most extraordinary observations at the end of its long life.”

The mission team hopes to gain powerful insights into the planet’s internal structure and the origins of the rings, obtain the first-ever sampling of Saturn’s atmosphere and particles coming from the main rings, and capture the closest-ever views of Saturn’s clouds and inner rings. The team currently is making final checks on the list of commands the robotic probe will follow to carry out its science observations, called a sequence, as it begins the finale. That sequence is scheduled to be uploaded to the spacecraft on Tuesday, April 11.

Cassini will transition to its grand finale orbits, with a last close flyby of Saturn’s giant moon Titan, on Saturday, April 22. As it has many times over the course of the mission, Titan’s gravity will bend Cassini’s flight path. Cassini’s orbit then will shrink so that instead of making its closest approach to Saturn just outside the rings, it will begin passing between the planet and the inner edge of its rings.

“Based on our best models, we expect the gap to be clear of particles large enough to damage the spacecraft. But we’re also being cautious by using our large antenna as a shield on the first pass, as we determine whether it’s safe to expose the science instruments to that environment on future passes,” said Earl Maize, Cassini project manager at JPL. “Certainly there are some unknowns, but that’s one of the reasons we’re doing this kind of daring exploration at the end of the mission.”

In mid-September, following a distant encounter with Titan, the spacecraft’s path will be bent so that it dives into the planet. When Cassini makes its final plunge into Saturn’s atmosphere on Sept. 15, it will send data from several instruments – most notably, data on the atmosphere’s composition – until its signal is lost.

“Cassini’s grand finale is so much more than a final plunge,” said Spilker. “It’s a thrilling final chapter for our intrepid spacecraft, and so scientifically rich that it was the clear and obvious choice for how to end the mission.”

Resources on Cassini’s grand finale, including images and video, are available at:

https://saturn.jpl.nasa.gov/mission/grand-finale/grand-finale-resources

An animated video about Cassini’s Grand Finale is available at:

https://youtu.be/xrGAQCq9BMU

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. JPL manages the mission for NASA’s Science Mission Directorate. JPL designed, developed and assembled the Cassini orbiter.

More information about Cassini is at:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

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Dwayne Brown / Laurie Cantillo
Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

Preston Dyches
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-7013
preston.dyches@jpl.nasa.gov

Editor: Karen Northon

 

Photo Credit: NASA

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Space Station Crew Cultivates Crystals for Drug Development

Crew members aboard the International Space Station will begin conducting research this week to improve the way we grow crystals on Earth. The information gained from the experiments could speed up the process for drug development, benefiting humans around the world.

Proteins serve an important role within the human body. Without them, the body wouldn’t be able to regulate, repair or protect itself. Many proteins are too small to be studied even under a microscope, and must be crystallized in order to determine their 3-D structures. These structures tell researchers how a single protein functions and its involvement in the development of disease. Once modeled, drug developers can use the structure to develop a specific drug to interact with the protein, a process called structure-based drug design.

Two investigations, The Effect of Macromolecular Transport on Microgravity Protein Crystallization (LMM Biophysics 1) and Growth Rate Dispersion as a Predictive Indicator for Biological Crystal Samples Where Quality Can be Improved with Microgravity Growth (LMM Biophysics 3), will study the formation of these crystals, looking at why microgravity-grown crystals often are of higher quality than Earth-grown, and which crystals may benefit from being grown in space.

Rate of Growth – LMM Biophysics 1

Researchers know that crystals grown in space often contain fewer imperfections than those grown on Earth, but the reasoning behind that phenomenon isn’t crystal clear. A widely accepted theory in the crystallography community is that the crystals are of higher quality because they grow slower in microgravity due to a lack of buoyancy-induced convection. The only way these protein molecules move in microgravity is by random diffusion, a process that is much slower than movement on Earth.

Another less-explored theory is that a higher level of purification can be achieved in microgravity. A pure crystal may contain thousands of copies of a single protein. Once crystals are returned to Earth and exposed to an X-Ray beam, the X-ray diffraction pattern can be used to mathematically map a protein’s structure.

“When you purify proteins to grow crystals, the protein molecules tend to stick to each other in a random fashion,” said Lawrence DeLucas, LMM Biophysics 1 primary investigator. “These protein aggregates can then incorporate into the growing crystals causing defects, disturbing the protein alignment, which then reduces the crystal’s X-ray diffraction quality.”

The theory states that in microgravity, a dimer, or two proteins stuck together, will move much slower than a monomer, or a single protein, giving aggregates less opportunity to incorporate into the crystal.

“You’re selecting out for predominantly monomer growth, and minimizing the amount of aggregates that are incorporated into the crystal because they move so much more slowly,” said DeLucas.

The LMM Biophysics 1 investigation will put these two theories to the test, to try to understand the reason(s) microgravity-grown crystals are often of superior quality and size compared to their Earth-grown counterparts. Improved X-ray diffraction data results in a more precise protein structure and thereby enhancing our understanding of the protein’s biological function and future drug discovery.

Crystal Types – LMM Biophysics 3

As LMM Biophysics 1 studies why space-grown crystals are of higher quality than Earth-grown crystals, LMM Biophysics 3 will take a look at which crystals may benefit from crystallization in space. Research has found that only some proteins crystallized in space benefit from microgravity growth. The shape and surface of the protein that makes up a crystal defines its potential for success in microgravity.

“Some proteins are like building blocks,” said Edward Snell, LMM Biophysics 3 primary investigator. “It’s very easy to stack them. Those are the ones that won’t benefit from microgravity. Others are like jelly beans. When you try and build a nice array of them on the ground, they want to roll away and not be ordered. Those are the ones that benefit from microgravity. What we’re trying to do is distinguish the blocks from the jelly beans.”

Understanding how different proteins crystallize in microgravity will give researchers a deeper view into how these proteins function, and help to determine which crystals should be transported to the space station for growth.

“We’re maximizing the use of a scarce resource, and making sure that every crystal we put up there benefits the scientists on the ground,” said Snell.

These crystals could be used in drug development and disease research around the world. Follow @ISS_Research for more information about the science happening on the space station.

Jenny Howard
International Space Station Program Science Office
Johnson Space Center

Editor: Kristine Rainey

 

Photo Credit: NASA

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Waves on Sun Give NASA New Insight into Space Weather Forecasting

Our sun is a chaotic place, simmering with magnetic energy and constantly spewing out particles. Sometimes the sun releases solar flares and coronal mass ejections — huge eruptions of charged particles — which contribute to space weather and can interfere with satellites and telecommunications on Earth. While it has long been hard to predict such events, new research has uncovered a mechanism that may help forecasting these explosions.

The research finds a phenomenon similar to a common weather system seen on our own planet. Weather on Earth reacts to the influence of jet streams, which blow air in narrow currents around the globe. These atmospheric currents are a type of Rossby wave, movements driven by the planet’s rotation. Using comprehensive imaging of the entire sun with data from the NASA heliophysics Solar Terrestrial Relations Observatory — STEREO — and Solar Dynamics Observatory — SDO — scientists have now found proof of Rossby waves on the sun.

The results, published in a new article in Nature Astronomy may allow for long-term space weather forecasting, thus helping better protect satellites and manned missions vulnerable to high-energy particles released from solar activity.

Rossby waves, large movement patterns in the atmosphere, have been found on the sun, and their discovery could help make better long-term space weather predictions.
Credits: NASA’s Goddard Space Flight Center/Genna Duberstein, Producer

“It’s not a huge surprise that these things exist on the sun. The cool part is what they do,” said lead author Scott McIntosh, director of the High Altitude Observatory at the National Center for Atmospheric Research in Boulder, Colorado. “Just like the jet stream and the gulf stream on Earth, these guys on the sun drive weather — space weather.”

Currently, we can forecast short-term effects after a solar flare erupts, but not the appearance of the flare itself. Understanding the solar Rossby waves and the interior process that drive them, may allow for predictions of when the solar flares might occur — an invaluable tool for future interplanetary manned missions which will fly through regions unprotected from the damaging energetic particles flares can release.

The scientists tracked coronal brightpoints — small, luminous features that can be observed on the sun, directly tied to magnetic activity beneath the surface — using data from 2010 to 2013 with NASA’s heliophysics fleet of space observatories.

In this north pole view of the sun, the brightpoints can be seen circling counter-clockwise, revealing the magnetized Rossby waves flowing beneath the surface.
Credits: NCAR High Altitude Observatory

“The main thing is we were able to observe Rossby waves because of STEREO A and STEREO B, in conjunction with SDO, which allowed us to get a full picture of the entire sun,” said co-author William Cramer, a graduate student at Yale University in New Haven, Connecticut.

The STEREO mission used two near-identical observatories in orbit ahead and behind Earth, STEREO A and STEREO B, to get a complete 360-degree view of the sun.

“These missions allowed the researchers to see the entire sun for over three years, something that would not be possible without the STEREO mission,” said Terry Kuchera, STEREO project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. In October 2014, after eight years in orbit, STEREO B lost contact with ground operations, but the multi-point view STEREO offers remains invaluable. “Having more than one vantage point to look at the sun has a lot of uses, and even with just STEREO A and SDO we can understand how events, like coronal mass ejections, move through the solar system better than we can with just one eye on the sun.”

The results clearly show trains of brightpoints slowly circling the sun traveling westwards, revealing the magnetized Rossby waves flowing beneath the surface. The researchers also found the brightpoints shed light on the solar cycle — the sun’s 22-year activity cycle, driven by the constant movement of magnetic material inside the sun. The brightpoints may serve as a clue, linking how the solar cycle leads to increased numbers of solar flares every 11 years.

“These waves couple activity happening on instantaneous timescales with things that are happening on decadal and longer timescales,” McIntosh said. “What this points to, is that something that might at first glance appear random, like flares and coronal mass ejections, are probably governed at some level by the process that are driving the wave.”

When terrestrial satellites were first used to observe the jet stream on Earth, it allowed huge advances in predictive weather forecasting. These results show such forecasting advances may also be possible with observations of the entire sun simultaneously.

Related Links

Editor: Rob Garner

 

Photo Credit: NASA

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NASA to Preview ‘Grand Finale’ of Cassini Saturn Mission

NASA will hold a news conference at 3 p.m. EDT Tuesday, April 4, at the agency’s Jet Propulsion Laboratory (JPL) in Pasadena, California, to preview the beginning of Cassini’s final mission segment, known as the Grand Finale, which begins in late April. The briefing will air live on NASA Television and the agency’s website.

Cassini has been orbiting Saturn since June 2004, studying the planet, its rings and its moons. A final close flyby of Saturn’s moon Titan on April 22 will reshape the Cassini spacecraft’s orbit so that it begins its final series of 22 weekly dives through the unexplored gap between the planet and its rings. The first of these dives is planned for April 26. Following these closer-than-ever encounters with the giant planet, Cassini will make a mission-ending plunge into Saturn’s upper atmosphere on Sept. 15.

The panelists for the briefing are:

  • Jim Green, director of NASA’s Planetary Science Division at the agency’s headquarters in Washington
  • Earl Maize, Cassini project manager at JPL
  • Linda Spilker, Cassini project scientist at JPL
  • Joan Stupik, Cassini guidance and control engineer at JPL

Media who would like to attend the event at JPL must arrange access in advance by contacting Gina Fontes in the JPL Media Relations Office at 818-354-9380 or georgina.d.fontes@jpl.nasa.gov. Media who arrange access must bring to the event valid media credentials, and for non-U.S. citizens, valid passports.

To participate by phone, media must email their name and affiliation to georgina.d.fontes@jpl.nasa.gov by 8 a.m. April 4.

Media and the public also may ask questions during the briefing on Twitter using the hashtag #askNASA.

Supporting graphics, video and background information about Cassini’s Grand Finale will be posted before the briefing at:

http://saturn.jpl.nasa.gov/grandfinale

The Cassini mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. JPL, a division of Caltech in Pasadena, California, manages the mission for NASA’s Science Mission Directorate in Washington. JPL designed, developed and assembled the Cassini orbiter.

For more information about Cassini, go to:

http://www.nasa.gov/cassini

and

http://saturn.jpl.nasa.gov

Dwayne Brown / Laurie Cantillo
Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

Preston Dyches
Jet Propulsion Laboratory, Pasadena, Calif.
818-394-7013
preston.dyches@jpl.nasa.gov

Editor: Karen Northon

 

Photo Credit: NASA

You can follow The Systems Scientist on Twitter or Facebook.


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NASA Selects Mission to Study Churning Chaos in our Milky Way and Beyond

NASA has selected a science mission that will measure emissions from the interstellar medium, which is the cosmic material found between stars. This data will help scientists determine the life cycle of interstellar gas in our Milky Way galaxy, witness the formation and destruction of star-forming clouds, and understand the dynamics and gas flow in the vicinity of the center of our galaxy.

The Galactic/Extragalactic ULDB Spectroscopic Terahertz Observatory (GUSTO) mission, led by the principal investigator of the University of Arizona, Christopher Walker, will fly an Ultralong-Duration Balloon (ULDB) carrying a telescope with carbon, oxygen, and nitrogen emission line detectors. This unique combination of data will provide the spectral and spatial resolution information needed for Walker and his team to untangle the complexities of the interstellar medium, and map out large sections of the plane of our Milky Way galaxy and the nearby galaxy known as the Large Magellanic Cloud.

“GUSTO will provide the first complete study of all phases of the stellar life cycle, from the formation of molecular clouds, through star birth and evolution, to the formation of gas clouds and the re-initiation of the cycle,” said Paul Hertz, astrophysics division director in the Science Mission Directorate in Washington. “NASA has a great history of launching observatories in the Astrophysics Explorers Program with new and unique observational capabilities. GUSTO continues that tradition.”

The mission is targeted for launch in 2021 from McMurdo, Antarctica, and is expected to stay in the air between 100 to 170 days, depending on weather conditions. It will cost approximately $40 million, including the balloon launch funding and the cost of post-launch operations and data analysis.

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, is providing the mission operations, and the balloon platform where the instruments are mounted, known as the gondola. The University of Arizona in Tucson will provide the GUSTO telescope and instrument, which will incorporate detector technologies from NASA’s Jet Propulsion Laboratory in Pasadena, California, the Massachusetts Institute of Technology in Cambridge, Arizona State University in Tempe, and SRON Netherlands Institute for Space Research.

NASA’s Astrophysics Explorers Program requested proposals for mission of opportunity investigations in September 2014. A panel of NASA and other scientists and engineers reviewed two mission of opportunity concept studies selected from the eight proposals submitted at that time, and NASA has determined that GUSTO has the best potential for excellent science return with a feasible development plan.

NASA’s Explorers Program is the agency’s oldest continuous program and is designed to provide frequent, low-cost access to space using principal investigator-led space science investigations relevant to the astrophysics and heliophysics programs in agency’s Science Mission Directorate. The program has launched more than 90 missions. It began in 1958 with the Explorer 1, which discovered the Earth’s radiation belts, now called the Van Allen belt, named after the principal investigator. Another Explorer mission, the Cosmic Background Explorer, led to a Nobel Prize. NASA’s Goddard Space Flight Center in Greenbelt, Maryland manages the program for the Science Mission Directorate in Washington.

For more information on the Explorers Program, visit:

https://explorers.gsfc.nasa.gov

For more information on scientific balloons, visit:

https://www.nasa.gov/scientificballoons

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Felicia Chou
Headquarters, Washington
202-358-0257
felicia.chou@nasa.gov

Last Updated: March 24, 2017
Editor: Katherine Brown

Photo Credit: NASA

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