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  • richardmitnick 12:42 pm on August 6, 2019 Permalink | Reply
    Tags: "Ghosts of Ancient Explosions Live on in Stars Today", , , , Caltech, , , ,   

    From Caltech: “Ghosts of Ancient Explosions Live on in Stars Today” 

    Caltech Logo

    From Caltech

    August 05, 2019

    Contact
    Lori Dajose
    (626) 395‑1217
    ldajose@caltech.edu

    The chemical composition of certain stars gives clues about their predecessors, stars that have long since exploded and faded.

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    Image of a Type Ia supernova. Credit: Zwicky Transient Facility

    Zwicky Transient Facility (ZTF) instrument installed on the 1.2m diameter Samuel Oschin Telescope at Palomar Observatory in California. Courtesy Caltech Optical Observatories

    Edwin Hubble at Caltech Palomar Samuel Oschin 48 inch Telescope, (credit: Emilio Segre Visual Archives/AIP/SPL)

    Caltech Palomar Intermediate Palomar Transient Factory telescope at the Samuel Oschin Telescope at Palomar Observatory,located in San Diego County, California, United States, altitude 1,712 m (5,617 ft)

    Caltech Palomar Samuel Oschin 48 inch Telescope, located in San Diego County, California, United States, altitude 1,712 m (5,617 ft)

    When small, dense stars called white dwarfs explode, they produce bright, short-lived flares called Type Ia supernovae. These supernovae are informative cosmological markers for astronomers—for example, they were used to prove that the universe is accelerating in its expansion.

    White dwarfs are not all the same, ranging from half of the mass of our sun to almost 50 percent more massive than our sun. Some explode in Type Ia supernovae; others simply die quietly. Now, by studying the “fossils” of long-exploded white dwarfs, Caltech astronomers have found that early on in the universe, white dwarfs often exploded at lower masses than they do today. This discovery indicates that a white dwarf could explode from a variety of causes, and does not necessarily have to reach a critical mass before exploding.

    A paper about the research, led by Evan Kirby, assistant professor of astronomy, appears in The Astrophysical Journal.

    Near the end of their lives, a majority of stars like our sun dwindle down into dim, dense white dwarfs, with all their mass packed into a space about the size of Earth. Sometimes, white dwarfs explode in what’s called a Type Ia (pronounced one-A) supernova.

    It is uncertain why some white dwarfs explode while others do not. In the early 1900s, an astrophysicist named Subrahmanyan Chandrasekhar calculated that if a white dwarf had more than 1.4 times the mass of our sun, it would explode in a Type Ia supernova. This mass was dubbed the Chandrasekhar mass. Though Chandrasekhar’s calculations gave one explanation for why some more massive white dwarfs explode, it did not explain why other white dwarfs less than 1.4 solar masses also explode.

    Studying Type Ia supernovae is a time-sensitive process; they flare into existence and fade back into darkness all within a few months. To study long-gone supernovae and the white dwarfs that produced them, Kirby and his team use a technique colloquially called galactic archaeology.

    Galactic archaeology is the process of looking for chemical signatures of long-past explosions in other stars. When a white dwarf explodes in a Type Ia supernova, it pollutes its galactic environment with elements forged in the explosion—heavy elements like nickel and iron. The more massive a star is when it explodes, the more heavy elements will be formed in the supernova. Then, those elements become incorporated into any newly forming stars in that region. Just as fossils today give clues about animals that have long ceased to exist, the amounts of nickel in stars illustrates how massive their long-exploded predecessors must have been.

    Using the Keck II telescope, Kirby and his team first looked at certain ancient galaxies, those that ran out of material to form stars in the first billion years of the universe’s life.

    Keck 2 telescope Maunakea Hawaii USA, 4,207 m (13,802 ft)

    Most of the stars in these galaxies, the team found, had relatively low nickel content. This meant that the exploded white dwarfs that gave them that nickel must have been relatively low mass—about as massive as the sun, lower than the Chandrasekhar mass.

    Yet, the researchers found that the nickel content was higher in more recently formed galaxies, meaning that as more time went by since the Big Bang, white dwarfs had begun to explode at higher masses.

    “We found that, in the early universe, white dwarfs were exploding at lower masses than later in the universe’s lifetime,” says Kirby.”It’s still unclear what has driven this change.”

    Understanding the processes that result in Type Ia supernovae is important because the explosions themselves are useful tools for making measurements of the universe. Regardless of how they exploded, most Type Ia supernovae follow a well-characterized relationship between their luminosity and the time it takes for them to fade.

    “We call Type Ia supernovae ‘standardizable candles.’

    Standard Candles to measure age and distance of the universe from supernovae NASA

    If you look at a candle at a distance, it will look dimmer than when it’s up close. If you know how bright it is supposed to be up close, and you measure how bright it is at a distance, you can calculate that distance,” says Kirby. “Type Ia supernovae have been very useful in calculating things like the rate of expansion of the universe. We use them all the time in cosmology. So, it’s important to understand where they come from and characterize the white dwarfs that generate these explosions.”

    The next steps are to study elements other than nickel, in particular, manganese. Manganese production is very sensitive to the mass of the supernova that produces it, and therefore gives a precise way to validate the conclusions drawn by the nickel content.

    The paper is titled Evidence for Sub-Chandrasekhar Type Ia Supernovae from Stellar Abundances in Dwarf Galaxies. In addition to Kirby, co-authors are Justin L. Xie and Rachel Guo of Harvard University, Caltech graduate student Mithi A. C. de los Reyes, Maria Bergemann and Mikhail Kovalev of the Max Planck Institute for Astronomy, Ken J. Shen of University of California Berkeley, and Anthony L. Piro and Andrew McWilliam of the Observatories of the Carnegie Institution for Science. Funding was provided by the National Science Foundation, a Cottrell Scholar award from the Research Corporation for Science Advancement, and Caltech.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 3:41 pm on July 24, 2019 Permalink | Reply
    Tags: "Seismologists Monitor Ridgecrest Aftershocks Using Novel Fiber Optic Network", Caltech, Ridgecrest earthquakes   

    From Caltech: “Seismologists Monitor Ridgecrest Aftershocks Using Novel Fiber Optic Network” 

    Caltech Logo

    From Caltech

    1

    July 24, 2019

    Written by
    Robert Perkins

    Contact
    Emily Velasco
    626‑395‑6487
    evelasco@caltech.edu

    Seismologists from Caltech are using fiber optic cables to monitor and record the aftershocks from the 2019 Ridgecrest earthquake sequence in greater detail than previously possible. Thousands of tiny aftershocks are occurring throughout the region each day, an unprecedented number of which will now be able to be tracked and studied.

    The nascent technique involves shooting a beam of light down a “dark,” or unused, fiber optic cable. When the beam hits tiny imperfections in the cable, a miniscule portion of the light is reflected back and recorded.

    In this manner, each imperfection acts as a trackable waypoint along the fiber optic cable, which is typically buried several feet beneath the earth’s surface. Seismic waves moving through the ground cause the cable to expand and contract minutely, which changes the travel time of light to and from these waypoints. By monitoring these changes, seismologists can observe the motion of seismic waves.

    “These imperfections occur frequently enough that every few meters of fiber act like an individual seismometer. For the 50 kilometers of fiber optic cable in three different locations we’ve tapped into for the project, it’s roughly akin to deploying over 6,000 seismometers in the area,” says Zhongwen Zhan, assistant professor of geophysics, who is leading the effort.

    The project was launched just days after the two large earthquakes struck the Ridgecrest area. Zhan called around, searching for unused fiber optic cable that would be long enough and close enough to the seismically active region to be useful. Eventually, the manager of the Inyokern Airport, Scott Seymour (who had also offered the use of the fiber network around the airport), connected Zhan with Michael Ort, the chief executive officer of the California Broadband Cooperative’s Digital 395 project. The project aims to build a new 583-mile fiber network that mainly follows the U.S. Route 395, which runs north-south along the eastern side of the Sierra Nevada, passing near Ridgecrest.

    Digital 395 has offered to let Zhan use three segments of its fiber optic cable: 10 kilometers from Ridgecrest to the west, and two sections both to the north and south of Olancha, near which there was intense seismic activity triggered by the M7.1 quake. “The July 4–5 earthquakes created a 50-kilometer-long rupture that has triggered aftershocks in separate regions that we’ll be able to study,” Zhan says. Meanwhile, the sensing instruments that Zhan connected to the fiber optic cable for the project were provided by manufacturers OptaSense and Silixa.

    Zhan’s team also deployed farther south at the Goldstone Deep Space Communications Complex, a NASA facility run by JPL. (JPL is managed by Caltech for NASA.) The site, which is close to Fort Irwin, hosts a dark fiber network that Zhan previously used to test the fiber optic seismic monitoring technology. “It’s only about 70 kilometers from Ridgecrest, so this would be a good time go back,” he says.

    Immediately after the earthquake, the USGS also deployed temporary seismometers around Ridgecrest to monitor aftershocks. Zhan says his fiber optic system will complement rather than duplicate that effort. The temporary seismometers are able to cover a wider area but produce sparser readings, he says. They also tend to be battery operated and nonnetworked, meaning that the data they record will not be available until after their batteries run down and are retrieved, while a portion of the data from Zhan’s fiber optic system will be available immediately.

    Though the Ridgecrest seismic monitoring will be temporary, Zhan and his colleagues hope to establish similar systems permanently in key cities throughout Southern California. This work began with a pilot project in 2018 involving the Caltech Seismological Laboratory and the City of Pasadena to use a portion of the city’s dark fiber to monitor temblors in the area.

    “The combination of the Pasadena fiber array and the Ridgecrest deployments have provided two important science firsts: the Pasadena array is the first example of a permanent earthquake monitoring system using fiber optics, while the Ridgecrest deployments, also a first in earthquake monitoring, give us a glimpse of what we could see if we were able to continuously light up dark fiber throughout Southern California,” says Michael Gurnis, John E. and Hazel S. Smits Professor of Geophysics and director of the Caltech Seismological Laboratory. “They allow us to observe and understand how seismic waves reverberate through our complex mountains and basins following a major temblor.”

    The information collected from the Ridgecrest fiber network will help seismologists learn more about how earthquake sequences decay and migrate through the earth, and will offer more details about how seismic waves move throughout the region around Ridgecrest.

    Processing the large volume of data that the fiber optic system is gathering will take months, even using automated systems, says Zhan, who estimates that his team will receive on the order of 10 to 20 terabytes of data over the next few months.

    “This will keep us busy for a while, but in the end, we’ll have a clearer picture of how this sequence evolved than would otherwise be possible,” Zhan says.

    This research is funded by a National Science Foundation CAREER Award, Caltech trustee Li Lu, and the Caltech-JPL President’s and Director’s Research and Development Fund.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 11:33 am on July 19, 2019 Permalink | Reply
    Tags: Caltech, Dr. Jennifer Andrews, , , , , The Seismo Lab at Caltech,   

    From Caltech: Women in STEM “What is it Like to be a Caltech Seismologist During a Big Quake?” Dr. Jennifer Andrews 

    Caltech Logo

    From Caltech

    July 18, 2019
    Robert Perkins
    (626) 395‑1862
    rperkins@caltech.edu

    When an earthquake strikes, seismologists at Caltech’s Seismological Laboratory spring into action.

    2

    1
    Dr. Jennifer Andrews

    An arm of Caltech’s Division of Geological and Planetary Sciences (GPS), the Seismo Lab is home to dozens of seismologists who collaborate with the United States Geological Survey (USGS) to operate one of the largest seismic networks in the nation.Together, they analyze data to provide the public with information about where the quake occurred and how big it was. That information not only helps first responders, but feeds into the scientific understanding on earthquakes and when and where the next big quicks are likely to strike.

    After the two largest Ridgecrest earthquakes on July 4 and 5 (Magnitude 6.4 and 7.1, respectively), Caltech staff seismologist Jen Andrews was part of the Seismo Lab team that rushed to respond. Recently, she described that experience.

    Where were you when the earthquakes hit?

    For Thursday’s quake, I was at home in my shower. I didn’t even realize at the time that it was a quake. But when I got out and looked at my computer, I saw the report. Then the phone rang, and it was Egill [Hauksson, research professor of geophysics at Caltech], saying it was time to go to work. It was all hands on deck.

    For Friday’s quake, I was at the ballet at the Dorothy Chandler Pavilion in Downtown Los Angeles. They’d just finished act 1 and were in intermission, so fortunately no dancers were on stage to be knocked off their feet. I was in the balcony, so the movement I felt was probably amplified by the height (and also the soft sediment beneath Downtown). The chandeliers were swaying, but no one panicked. As soon as I felt it shake, I started counting. We felt it as a roll, so I knew the epicenter wasn’t right beneath us. Once I reached 20 seconds, I knew this was a big earthquake, even bigger than the first one. I immediately got in a taxi and headed straight to campus.

    What did you do next?

    Here at the Seismo Lab, it’s our responsibility to verify that all of the info we’re putting out about earthquakes—the locations and magnitudes, for example—are correct. We’re responsible for getting info about the origin out within two minutes of the shaking, so we have fully automated systems that send updates to the National Earthquake Information Center right away. All of that happens without anyone touching anything, before we can even get to our desks. But once we get there, we look at the waveforms and make sure that we’re correctly identifying the P and S waves. [During an earthquake, several types of seismic waves radiate out from the quake’s epicenter, including compressional waves (or P-waves), transverse waves (or S-waves), and surface waves.] We also know the speed at which seismic waves should travel, so we can use that to make sure that we’re correctly identifying where the quake originated. It turns out that the automatic systems did a brilliant job of getting most of the information correct.

    What is it like to be in the Seismo Lab after a big earthquake?

    It’s very busy. There’s a lot of people: seismologists, news reporters, even curious students and people who are on campus who just want to know what’s going on. Meanwhile, we have a lot of issues to deal with: we have seismologists on the phone with state representatives and others speaking to members of the press, while still others are trying to process data coming in from seismometers. Within a few hours of a quake, the USGS tries to figure out who’s going out to the location of the earthquake, and what equipment they’ll be taking. For the Ridgecrest quakes, they did flyovers in a helicopter looking for ruptures, and then sent people on the ground to measure the rupture. They then deployed additional seismometers so that we could get an even clearer picture of any aftershocks.

    How long after the earthquake will things stay busy for you?

    The media attention relaxes after a few hours or days, but I’m going to be looking at the data we gathered from these quakes for a long time. I was here every day over the holiday weekend and the following week working on it. It could take months or even years for our group to process all the data.

    Do you learn more from big earthquakes like these than you do from little ones?

    You learn different things. The data will be incorporated into earthquake hazard models, though likely will not make big changes. But these quakes in particular were interesting, as two perpendicular faults were involved. We can study the rupture dynamics, which you can’t resolve in smaller quakes. Also, having two strong quakes caused variations in fault slip and ground motion that will be important to study and understand.

    See the full article here .

    Earthquake Alert

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    Earthquake Alert

    Earthquake Network projectEarthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 1:53 pm on July 8, 2019 Permalink | Reply
    Tags: , , Atira asteroid 2019 LF6, , , Caltech, , We only have about 20 to 30 minutes before sunrise or after sunset to find these asteroids, ZTF has so far found around 100 near-Earth asteroids and about 2000 asteroids orbiting in the Main Belt between Mars and Jupiter.,   

    From Caltech: “ZTF Spots Asteroid with Shortest Year” 

    Caltech Logo

    From Caltech

    Whitney Clavin
    (626) 395‑1856
    wclavin@caltech.edu

    4
    The newfound kilometer-size object orbits the sun every 151 days

    July 08, 2019

    Astronomers have spotted an unusual asteroid with the shortest “year” known for any asteroid. The rocky body, dubbed 2019 LF6, is about a kilometer in size and circles the sun roughly every 151 days. In its orbit, the asteroid swings out beyond Venus and, at times, comes closer in than Mercury, which circles the sun every 88 days. 2019 LF6 is one of only 20 known “Atira” asteroids, whose orbits fall entirely within Earth’s.

    “You don’t find kilometer-size asteroids very often these days,” says Quanzhi Ye, a postdoctoral scholar at Caltech who discovered 2019 LF6 and works with Tom Prince, the Ira S. Bowen Professor of Physics at Caltech and a senior research scientist at JPL, and George Helou, the executive director of IPAC, an astronomy center at Caltech.

    “Thirty years ago, people started organizing methodical asteroid searches, finding larger objects first, but now that most of them have been found, the bigger ones are rare birds,” he says. “LF6 is very unusual both in orbit and in size—its unique orbit explains why such a large asteroid eluded several decades of careful searches.”

    2019 LF6 was discovered via the Zwicky Transient Facility, or ZTF, a state-of-the-art camera at the Palomar Observatory that scans the skies every night for transient objects, such as exploding and flashing stars and moving asteroids. Because ZTF scans the sky so rapidly, it is well-suited for finding Atira asteroids, which have short observing windows.

    Zwicky Transient Facility (ZTF) instrument installed on the 1.2m diameter Samuel Oschin Telescope at Palomar Observatory in California. Courtesy Caltech Optical Observatories

    “We only have about 20 to 30 minutes before sunrise or after sunset to find these asteroids,” says Ye.

    To find the Atira asteroids, the ZTF team has been carrying out a dedicated observing campaign, named Twilight after the time of day best suited for discovering the objects. Twilight was developed by Ye and Wing-Huen Ip of the National Central University in Taiwan. So far, the program has discovered one other Atira asteroid, named 2019 AQ3. Before 2019 LF6 came along, 2019 AQ3 had the shortest known year of any asteroid, orbiting the sun roughly every 165 days.

    “Both of the large Atira asteroids that were found by ZTF orbit well outside the plane of the solar system,” says Prince. “This suggests that sometime in the past they were flung out of the plane of the solar system because they came too close to Venus or Mercury,” says Prince.

    In addition to the two Atira objects, ZTF has so far found around 100 near-Earth asteroids and about 2,000 asteroids orbiting in the Main Belt between Mars and Jupiter.

    Ye says he hopes the Twilight program will lead to more Atira discoveries, and he looks forward to the possible selection by NASA of the Near-Earth Object Camera (NEOCam) mission, a proposed spacecraft designed to look for asteroids closer to the sun than previous surveys. NEOCam would pick up the infrared, or heat, signatures of asteroids. (Ye works at IPAC, which would process and archive data for the NEOCam mission, but is not part of that team.)

    “Because Atira asteroids are closer to the sun and warmer than other asteroids, they are brighter in the infrared,” says Helou.”NEOCam has the double advantage of its location in space and its infrared capability to find these asteroids more easily than telescopes working at visible wavelengths from the ground.”

    The International Astronomical Union Minor Planet Center listing for 2019 LF6 is at https://minorplanetcenter.net/mpec/K19/K19M45.html.

    ZTF is funded by the National Science Foundationand an international collaboration of partners. Additional support comes from the Heising-Simons Foundation, and Caltech itself. ZTF data are processed and archived by IPAC. NASA supports ZTF’s search for near-Earth objects through the Near-Earth Object Observations program.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 12:14 pm on July 3, 2019 Permalink | Reply
    Tags: "Seeing Farther and Deeper: An Interview with Katie Bouman", , , Caltech, Computer vision and imaging,   

    From Caltech: Women in STEM- “Seeing Farther and Deeper: An Interview with Katie Bouman” 

    Caltech Logo

    From Caltech

    July 02, 2019

    Robert Perkins
    (626) 395‑1862
    rperkins@caltech.edu

    1

    New Caltech faculty member Katie Bouman creates images from nonideal sensor data and mines for information from images using techniques that can be applied to everything from medical imaging to studying the universe.

    An assistant professor of computing and mathematical sciences in the Division of Engineering and Applied Science, Bouman joined Caltech’s faculty at the beginning of June. She earned her bachelor’s degree at the University of Michigan in Ann Arbor, followed by a master’s and PhD from MIT. After completing her graduate studies, she worked as a postdoctoral researcher at the Harvard-Smithsonian Center for Astrophysics. Bouman was one of about 200 scientists and engineers from across the globe who worked on the Event Horizon Telescope project, which made headlines in April for capturing the first-ever image of a black hole.

    Recently, Bouman answered a few questions about her life and work.

    How would you describe your research?

    I like thinking about how we can use imaging to help push forward the boundaries of other fields. I did my PhD in a computer vision group—a group that tries to analyze images and understand images. A lot of people in the computer vision field work on object detection and action recognition. Those are really interesting problems, and researchers have been working for decades to build machines that mimic human intelligence in order to solve them. But there is another world of interesting problems that cameras and images can help us solve that humans are not even capable of doing on their own.

    I like to search for information hidden in images, imperceptible to humans, that we can use to learn about the environment around us. This requires an understanding of the complete sensing system: how light interacts with the world and is then captured by our camera sensor into individual pixels. This line of research, where we work on merging sensors and algorithms to achieve something not possible with just one or the other, is often described as computational imaging or computational photography.

    What kind of applications do you see for this work?

    There are multiple sides to the research I enjoy: one side is coming up with new ways to reconstruct images invisible to traditional sensors, and another side is using images or videos to extract hidden information from a scene. For instance, I’ve used each pixel in a video like a very noisy sensor to recover the location of people moving behind a wall from imperceptible changes in shadows that appear on the ground. I’ve also used data to create an image. For example, in the black hole imaging work, we had really noisy, sparse data. We had to figure out how to create an image to learn something from what we were seeing.

    Here at Caltech, I’m excited to start connecting with people across campus and help them use imaging to push the boundaries of their disciplines. I’ve already had the opportunity to speak with Zach Ross [assistant professor of geophysics] about how new techniques could help in more precisely localizing the origin of collections of earthquakes. This work, perhaps surprisingly, contains many similarities to the work I’ve done in black hole imaging.

    I also will be having Aviad Levis join me as postdoc next year. Aviad has been working with JPL on studying cloud tomography: reconstructing the 3D structure and the particle distribution of clouds from 2D images taken by planes or satellites. Similar to imaging black holes, these clouds evolve as the measurements are being taken, so every measurement captures a different sample of the cloud structure. We are excited about exploring some ideas for solving both of these messy, time-evolving problems. By intelligently connecting the information from time-variable measurements, I’m confident we can design algorithms to solve for a more accurate cloud structure or a video of a black hole evolving over time.

    Each problem, each application, has its own intricacies; understanding the structure of a problem is exciting, and by encoding that structure into our algorithms, we can learn more.

    I understand that you’re not the only Bouman on campus right now.

    That’s right. My sister, Amanda, is a graduate student in mechanical engineering, and my brother, Alexander, is an undergraduate also in mechanical engineering. It’s definitely been nice having them around to show me the ropes and help me get settled on campus.

    After living on the East Coast, how do you like being in California?

    My husband and I are really enjoying it, but we’re still getting used to it. It seems like every day I tell him that we need to eat outside because it’s so beautiful, so we end up grilling outside every day. In Boston, we had to take advantage of every nice day. Eventually, we’re going to have to stop eating just hamburgers and hot dogs.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 11:05 am on July 2, 2019 Permalink | Reply
    Tags: , "When we used Palomar's CWI previously we were able to see what looked like a rotating disk of gas but we couldn't make out any filaments" says O'Sullivan., , , , Caltech, , In 2017 Martin and his team used KCWI to acquire data on two active galaxies known as quasars named UM 287 and CSO 38., KCWI designed and built at Caltech is a state-of-the-art spectral imaging camera., , Nearby UM 287 and CSO 38 is a giant nebula larger than the Milky Way and visible thanks to the strong illumination of the quasars., New observations of the Keck Cosmic Web Imager (KCWI) at Keck Observatory now provide the clearest most direct evidence yet that filaments of cool gas spiral into young galaxies., The instrument was used to study the nature of dark matter black holes and to refine our understanding of star formation., The main driver for building KCWI was understanding and characterizing the cosmic web   

    From Caltech: “Spiraling Filaments Feed Young Galaxies” 

    Caltech Logo

    From Caltech

    July 01, 2019

    Whitney Clavin
    (626) 395‑1856
    wclavin@caltech.edu

    1

    New data from the Keck Observatory show gas directly spiraling into growing galaxies.

    Galaxies grow by accumulating gas from their surroundings and converting it to stars, but the details of this process have remained murky. New observations, made using the Keck Cosmic Web Imager (KCWI) at the W. M. Keck Observatory in Hawaii, now provide the clearest, most direct evidence yet that filaments of cool gas spiral into young galaxies, supplying the fuel for stars.

    Keck Cosmic Web Imager on Keck 2 schematic

    Keck Cosmic Web Imager on Keck 2

    Keck Observatory, operated by Caltech and the University of California, Maunakea, Hawaii, USA.4,207 m (13,802 ft), above sea level,

    2
    Chris Martin, the principal investigator of the Keck Cosmic Web Imager, inspects the instrument in a clean room at Caltech. Credit: Caltech

    “For the first time, we are seeing filaments of gas directly spiral into a galaxy. It’s like a pipeline going straight in,” says Christopher Martin, a professor of physics at Caltech and lead author of a new paper appearing in the July 1 issue of the journal Nature Astronomy. “This pipeline of gas sustains star formation, explaining how galaxies can make stars on very fast timescales.”

    For years, astronomers have debated exactly how gas makes its way to the center of galaxies. Does it heat up dramatically as it collides with the surrounding hot gas? Or does it stream in along thin dense filaments, remaining relatively cold? “Modern theory suggests that the answer is probably a mix of both, but proving the existence of these cold streams of gas had remained a major challenge until now,” says co-author Donal O’Sullivan (MS ’15), a PhD student in Martin’s group who built part of KCWI.

    KCWI, designed and built at Caltech, is a state-of-the-art spectral imaging camera. Called an integral-field unit spectrograph, it allows astronomers to take images such that every pixel in the image contains a dispersed spectrum of light. Installed at Keck in early 2017, KCWI is the successor to the Cosmic Web Imager (CWI), an instrument that has operated at Palomar Observatory near San Diego since 2010. KCWI has eight times the spatial resolution and 10 times the sensitivity of CWI.

    “The main driver for building KCWI was understanding and characterizing the cosmic web, but the instrument is very flexible, and scientists have used it, among other things, to study the nature of dark matter, to investigate black holes, and to refine our understanding of star formation,” says co-author Mateusz (Matt) Matuszewski (MS ’02, PhD ’12), a senior instrument scientist at Caltech.

    The question of how galaxies and stars form out of a network of wispy filaments in space—what is known as the cosmic web—has fascinated Martin since he was a graduate student. To find answers, he led the teams that built both CWI and KCWI. In 2017, Martin and his team used KCWI to acquire data on two active galaxies known as quasars, named UM 287 and CSO 38, but it was not the quasars themselves they wanted to study. Nearby each of these two quasars is a giant nebula, larger than the Milky Way and visible thanks to the strong illumination of the quasars. By looking at light emitted by hydrogen in the nebulas—specifically an atomic emission line called hydrogen Lyman-alpha—they were able to map the velocity of the gas. From previous observations at Palomar, the team already knew there were signs of rotation in the nebulas, but the Keck data revealed much more.

    “When we used Palomar’s CWI previously, we were able to see what looked like a rotating disk of gas, but we couldn’t make out any filaments,” says O’Sullivan. “Now, with the increase in sensitivity and resolution with KCWI, we have more sophisticated models and can see that these objects are being fed by gas flowing in from attached filaments, which is strong evidence that the cosmic web is connected to and fueling this disk.”

    Martin and colleagues developed a mathematical model to explain the velocities they were seeing in the gas and tested it on UM287 and CSO38 as well as on a simulated galaxy.

    “It took us more than a year to come up with the mathematical model to explain the radial flow of the gas,” says Martin. “Once we did, we were shocked by how well the model works.”

    The findings provide the best evidence to date for the cold-flow model of galaxy formation, which basically states that cool gas can flow directly into forming galaxies, where it is converted into stars. Before this model came into popularity, researchers had proposed that galaxies pull in gas and heat it up to extremely high temperatures. From there, the gas was thought to gradually cool, providing a steady but slow supply of fuel for stars. In 1996, research from Caltech’s Charles (Chuck) Steidel, the Lee A. DuBridge Professor of Astronomy and a co-author of the new study, threw this model into question. He and his colleagues showed that distant galaxies produce stars at a very high rate—too fast to be accounted for by the slow settling and cooling of hot gas that was a favored model for young galaxy fueling.

    “Through the years, we’ve acquired more and more evidence for the cold-flow model,” says Martin. “We have nicknamed our new version of the model the ‘cold-flow inspiral,’ since we see the spiraling pattern in the gas.”

    “These type of measurements are exactly the kind of science we want to do with KCWI,” says John O’Meara, the Keck Observatory chief scientist. “We combine the power of Keck’s telescope size, powerful instrumentation, and an amazing astronomical site to push the boundaries of what’s possible to observe. It’s very exciting to see this result in particular, since directly observing inflows has been something of a missing link in our ability to test models of galaxy formation and evolution. I can’t wait to see what’s coming next.”

    The new study, titled, “Multi-Filament Inflows Fuel Young Star Forming Galaxies,” was funded by the National Science Foundation (NSF), the W. M. Keck Observatory, Caltech, and the European Research Council. KCWI is funded by NSF, Keck Observatory, the Heising-Simons Founcation and Caltech. The galaxy simulations were performed at NASA Advanced Supercomputing at NASA Ames Research Center. Other Caltech authors include former postdoc Erika Hamden, now at the University of Arizona; Patrick Morrissey, a visitor in space astrophysics who also works at JPL, which is managed by Caltech for NASA; and research scientist James D. (Don) Neill.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 9:33 am on June 27, 2019 Permalink | Reply
    Tags: Caltech, Can AI Be Fair?   

    From Caltech: “Can AI Be Fair?” 

    Caltech Logo

    From Caltech

    6.26.19

    Whitney Clavin
    (626) 395‑1856
    wclavin@caltech.edu

    1

    A Caltech workshop posed this question to computer scientists, philosophers, and other experts.

    Experts from across the country in computer science, philosophy, law, and other fields gathered June 10-12 in Caltech’s Baxter Hall to discuss a hot topic in some academic circles: Can artificial intelligences, or machine-learning algorithms, be fair?

    The experts were part of the Decisions, Games, and Logic workshop, organized primarily by Boris Babic, the Weisman Postdoctoral Instructor in Philosophy of Science at Caltech. Babic says he got the idea for the workshop after teaching a seminar called Statistics, Ethics & Law in the Division of the Humanities and Social Sciences. One of the activities in the class involved looking through studies investigating the fairness of machine-learning programs, or algorithms, used for making predictions in college admissions, employment, bank lending, and criminal justice.

    “The amount of literature out there about ethical constraints on machine learning has exploded,” says Babic. “One key question is: Is there a way to provide guarantees or safeguards that these machine-learning algorithms are not going to produce what we deem unfair effects across different demographic subgroups, such as those based on race or gender?”

    Babic says interest in the field of AI and fairness was ignited after a 2016 investigative study by ProPublica claimed to find racial bias in a classification algorithm used by judges in Florida courts. The algorithm was designed to assess the risk that a convicted person would commit another crime, or recidivate. The judges would then use the calculated risk scores to help in making bail decisions. But, according to the ProPublica report, the algorithm would falsely identify a black person as being high risk more often than it would falsely identify a white person as high risk.

    “If you are training an algorithm on data that have preexisting biases—for example, from a police department that disproportionately targets minorities for petty crimes—then those biases will be reflected in the algorithm’s results,” says Babic. “A lot of researchers are looking into solutions to this problem.”

    At the workshop, various computer scientists talked about addressing these issues using specific types of machine-learning techniques. Machine-learning programs typically learn from so-called training data and then, from these data, come up with a model that makes predictions about the future. The goal is to attempt to remove any possible racial or other bias from the models.

    One speaker, Ilya Shpitser, a computer science professor at Johns Hopkins University, stressed the importance of “causal inference” techniques, which separate causal effects that are deemed unfair from those causal effects that are considered fair. This approach asks a “counterfactual” question—basically a “what if” question—about the decisions one would have made if the world had been fair. In other words, once unfair causal effects are identified—such as one’s race leading to different bail decisions in a court—the goal is to selectively remove those effects from an algorithm that makes automated decisions.

    But Shpitser also explained that one has to be careful about “proxies” in data, where something like racial bias may have seemingly been removed but is, in fact, still influencing the outcome via a proxy. He gave the example of African Americans receiving literacy tests in the South in the 1960s to determine if they could vote. If they did not pass the test, they could not vote. In this case, the test—the proxy—was an attempt to mask the racial bias.

    “We want to move to the fair world even though the real world has problems with it,” says Shpitser.

    Deborah Hellman, a professor of law at the University of Virginia, proposed what she thinks is the best way to measure fairness in machine-learning programs. She said that the numbers of false positives and false negatives derived from a machine-learning program should be looked at and compared for different groups. In the ProPublica example, false positives occurred when people were wrongly predicted to commit future crimes and false negatives occurred when people were wrongly predicted to not commit future crimes. Hellman says that by comparing the ratios of false positives to false negatives for different groups, such as black people and white people, one can determine whether an algorithm is fair or not. Misaligned ratios, she says, would be indicative of disparate treatments.

    Another speaker, David Danks, a professor of philosophy and psychology at Carnegie Mellon University, said he thinks we can sometimes trust machine-learning programs, even knowing that they are often imperfect and can have bias. He said there are some circumstances where the bias may not be relevant and would not cause harm. And, he says, there may even be situations where the bias can be used to determine which groups need more social support.

    Danks gave the example of a system that is designed to predict the best employees for a certain task but is biased against people who wear blue shirts. If nobody is wearing blue shirts, he explained, the system can be trusted. “It’s carrying out my values even though it’s biased. … The harm comes when the prediction is used.”

    In the end, the participants of the workshop said they thought the cross-disciplinary nature of the workshop was tremendously useful.

    “Fairness in automated-decision procedures is a problem that cuts across disciplines,” says Frederick Eberhardt, professor of philosophy at Caltech. “We need to understand what we actually want and mean by fairness, we have to figure out how to implement it in modern AI technologies, and we have to ensure that these technologies are subject to the demands of the law and the public in ensuring scrutiny, recourse, and transparency. At the workshop, it was fascinating to see how the various experts would disagree in ways that were not aligned with their disciplinary backgrounds and to see how much everything was still in flux. There is a lot of work to be done in this area.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 12:17 pm on June 20, 2019 Permalink | Reply
    Tags: , , , Caltech, , Lunar Trailblazer,   

    From Caltech: “NASA Selects Caltech-Led Lunar Mission as a Finalist” 

    Caltech Logo

    From Caltech

    June 20, 2019

    NASA has selected a Caltech-led mission to send a small satellite to quantify and study water on the Moon. The project is one of three finalists selected from more than a dozen proposals for small satellite missions – at least one of which is expected to move to final selection and flight.

    1
    Lunar Trailblazer follows up on a key discovery by NASA’s Moon Mineralogy Mapper (M3) on the Indian Chandrayaan-1 mission: small amounts of water and hydroxyl (in blue and violet) across the surface of the moon, especially near the poles. Credit: ISRO/NASA/JPL-Caltech/Brown Univ./USGS

    3
    Left side of the Moon Mineralogy Mapper that was located on the Chandrayaan-1 lunar orbiter.

    3
    Chandrayaan-1

    The Lunar Trailblazer would follow up on one of the most surprising discoveries of the late 2000s: the detection of water on the Moon’s surface, long thought impossible because of its exposure to the vacuum of space. Trailblazer would map the tiny amounts of water and of hydroxyl (a compound of hydrogen and oxygen) on the sunlit side of the Moon, determining whether they change with time. Trailblazer would also peer into shadowed craters to map ice deposits, glimpses of which were observed on prior missions.

    The mission proposal is led by Bethany Ehlmann, professor of planetary science at Caltech and research scientist at JPL, which Caltech manages for NASA. “Our team is excited to move forward to map water on the Moon. The water cycle of airless bodies is one of the solar system’s most surprising occurrences and is important for the support of future human lunar exploration,” Ehlmann says.

    The relatively tiny Trailblazer satellite, which would measure just 5 meters in length with its solar panels fully deployed, would spend a year orbiting the Moon at a height of 100 kilometers, scanning it with two key instruments: a shortwave imaging spectrometer built by JPL and a multispectral thermal imager built by the University of Oxford.

    The spectrometer would image the surface in multiple wavelengths in the infrared, searching for the signature of water—either in the form of ice or bound to minerals. Meanwhile, the thermal imager would map the temperature, physical properties, and composition of regions where the spectrometer detects water.

    The end result would be a high-resolution map—at 100 meters per pixel—that charts the form, abundance, and distribution of water while also collecting information about the environments where that water exists. The mission’s leaders hope that such information could not only fill in the gaps of our understanding of the Moon but also chart a course for future human exploration.

    The mission was proposed as part of NASA’s Small Innovative Missions for Planetary Exploration (SIMPLEx) Program for low-budget missions that are capable of major planetary surveys. “We’re eager to lead the way in science and discovery using this new small-satellite NASA mission class. The opportunities are huge,” Ehlmann says.

    The mission will now receive funding for up to one year followed by a NASA preliminary design review. At that time, NASA will determine when and if it will be selected for a flight. The satellite could launch within two to four years, Ehlmann says. Caltech would be responsible for managing the project and for the scientific leadership, with support from JPL. Ball Aerospace in Boulder, Colorado, would build the spacecraft.

    Once launched, the spacecraft would be operated by teams from Caltech and neighboring Pasadena City College. The teams would include students who will be supported by experienced Caltech and JPL personnel. The project’s science team includes researchers from Caltech, JPL, the UK Space Agency, the University of Oxford, Pasadena City College, Johns Hopkins University Applied Physics Laboratory, Brown University, and Northern Arizona University.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 7:27 am on June 6, 2019 Permalink | Reply
    Tags: , Caltech, nEDM-neutron Electric Dipole Moment experiment,   

    From Caltech: “How a Giant ‘Thermos Bottle’ Will Help in Understanding Antimatter” 

    Caltech Logo

    From Caltech

    June 05, 2019

    Whitney Clavin
    (626) 395‑1856
    wclavin@caltech.edu

    1
    Members of the nEDM team stand in front of their magnetic cryovessel experimental apparatus in the Synchrotron Building at Caltech. From left to right: Wei Wanchun, research engineer; Marie Blatnick, graduate student, and Brad Filippone, the Francis L. Moseley Professor of Physics and Spokesperson for the nEDM experiment.

    One of the big questions physicists are trying to answer is what happened to all the antimatter in our universe. The universe was born out of a hot soup of both matter and antimatter particles (for example, the antiparticle to an electron is a positron). But something happened billions of years ago to tip the balance to matter, and antimatter disappeared. In fact, if this had not happened, we humans would not be here: when antimatter and matter particles collide, they transform into pure energy.

    To address this mystery, researchers at Caltech are taking part in an ambitious multi-institutional project called the neutron Electric Dipole Moment experiment, or nEDM, funded by the U.S. Department of Energy and the National Science Foundation. The project will culminate in an experiment at the Oak Ridge National Laboratory in Tennessee in about three years. The idea is to look for what is called an electric dipole moment in neutrons—a phenomenon in which the charges within a neutron are such that one side of the neutron is a tad more negative than the other. This distortion, if large enough, could signal a breakdown in a type of symmetry in physics called charge parity, or CP, that is needed to explain the absence of antimatter in the universe.

    Caltech is building a crucial part of the experiment—a giant cryovessel, pictured above, as well as magnetic shielding and coils to produce magnetic fields. The experiment inside the cryovessel, which can be thought of as a giant thermos bottle, will be chilled to temperatures as low as just one-half a degree above absolute zero, or 0.5 Kelvin (-459 degrees Fahrenheit). The idea is to spin ultracold neutrons in a magnetic field inside the chamber, in the same way that MRI machines spin protons in our bodies. An electric field would then be applied, and the researchers would look for very tiny changes in the way the neutrons are spinning—an indication of an electric dipole moment. The sensitivity of the nEDM experiment is equivalent to measuring a distortion in Earth’s diameter of less than one one-hundredth the thickness of a human hair.

    The Caltech team expects to deliver the cryovessel, with its magnetic shielding and magnetic field coils, to Oak Ridge in about a year and a half.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 8:18 am on May 11, 2019 Permalink | Reply
    Tags: , Beta-lactam; gamma-lactam: and delta-lactam molecules, , Caltech, , In the ongoing arms race with humans and their antibiotics on one side and bacteria with their ability to evolve defenses to antibiotics on the other humans have enlisted a new ally: other bacteria.   

    From Caltech: “Directed Evolution Opens Door to New Antibiotics” 

    Caltech Logo

    From Caltech

    May 09, 2019
    Emily Velasco
    626‑395‑6487
    evelasco@caltech.edu

    1
    Caltech

    In the ongoing arms race with humans and their antibiotics on one side, and bacteria with their ability to evolve defenses to antibiotics on the other, humans have enlisted a new ally—other bacteria.

    Many common antibiotics, including the most famous antibiotic, penicillin, are based around a molecular structure known as a beta-lactam ring. These drugs, aptly named beta-lactam antibiotics, interfere with a bacterium’s ability to build its cell wall.

    2
    Penicillin. Credit: Caltech

    As bacteria develop resistance to existing antibiotics, researchers and pharmaceutical companies work to create new ones. That means a lot of work is done creating new kinds of beta-lactams, and that is where Frances Arnold’s lab enters the picture.

    6
    Frances H. Arnold

    The paramount challenge is to control precisely where along the molecule the reaction takes place. With traditional synthetic chemistry, chemists have to tack extra pieces onto molecules that they want to turn into beta-lactams. Without those extra pieces, the knots will end up tied in inconsistent spots, resulting in some loops that are large and some that are small. That’s undesirable for someone trying to manufacture a consistent batch of antibiotics. But the addition of those extra pieces makes the synthesis more complicated because additional steps are required to add them and still more steps to remove them after the looping is complete.

    3
    Caltech
    Beta-lactams are made by taking a chainlike molecule and looping it, kind of like taking one end of a string and tying it in a knot to the middle of the string.

    Graduate student Inha Cho and postdoctoral scholar Zhi-Jun Jia, both from Arnold’s lab, have developed something simpler by using directed evolution, a technique developed by Arnold, the Linus Pauling Professor of Chemical Engineering, Bioengineering and Biochemistry, and director of the Donna and Benjamin M. Rosen Bioengineering Center. In directed evolution, which Arnold developed in the 1990s and for which she received the 2018 Nobel Prize in Chemistry, enzymes are evolved in a lab until they behave in a desired way. The genetic code of a useful enzyme is transferred into bacteria like Escherichia coli. As the bacteria grow, divide, and go about their lives, they churn out the enzyme.

    In this case, Cho and Jia took an enzyme known as cytochrome P450, which has been a versatile workhorse in the Arnold lab, and evolved it to produce beta-lactams. Two other versions of enzymes were also created to construct other ring sizes of lactams. One version creates a gamma-lactam, a loop of four carbon atoms and one nitrogen atom. And the other version creates a delta-lactam, a loop of five carbon atoms and one nitrogen atom.

    6
    The enzyme developed in Arnold’s lab can create beta-lactam, gamma-lactam, and delta-lactam molecules. Credit: Caltech

    “We’re developing new enzymes with activity that cannot be found in nature,” says Cho. “Lactams can be found in many different drugs, but especially in antibiotics, and we’re always needing new ones.”

    Jia points out that the enzymes they have created are also incredibly efficient, with each molecule of enzyme capable of producing up to one million beta-lactam molecules. “They represent the most efficient enzymes created in our lab, and are ready for industrial applications,” Jia says.

    The paper, titled “Site-selective enzymatic C-H amidation for synthesis of diverse lactams” and co-authored by Arnold, appears in the May 10 issue of Science.

    Support for the research was provided by the National Science Foundation, the Joseph J. Jacobs Institute for Molecular Engineering for Medicine, and Deutsche Forschungsgemeinschaft.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
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