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Adams, M. L.

Publications and source records attributed to Adams, M. L..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

A CME-Producing Solar Eruption from the Interior of an Emerging Bipolar Active Region

In a negative-polarity coronal hole, magnetic flux emergence, seen by the Solar Dynamics Observatory's {SDO) Helioseismic Magnetic lmager (HMI), begins at approximately 19:00 UT on March 3, 2016. The emerged magnetic field produced sunspots, which NOAA numbered 12514 two days later. The emerging magnetic field is largely bipolar with the opposite-polarity fluxes spreading apart overall, but there is simultaneously some convergence and cancellation of opposite-polarity flux at the polarity inversion line (PIL) inside the emerging bipole. In the first fifteen hours after emergence onset, three obvious eruptions occur, observed in the coronal EUV images from SDO's Atmospheric Imaging Assembly (AIA). The first two erupt from separate segments of the external PIL between the emerging positve-polarity flux and the extant surrounding negative-polarity flux, with the exploding magnetic field being prepared and triggered by flux cancellation at the external PIL. The emerging bipole shows obvious overall left-handed shear and/or twist in its magnetic field. The focus of th is poster is the third and largest eruption, which comes from inside the emerging bipole and blows it open to produce a CME observed by SOHO/LASCO. That eruption is preceded by flux cancellation at the emerging bipole's interior PIL, cancellation that plausibly builds a sheared and twisted flux rope above the interior PIL and finally triggers the blow-out eruption of the flux rope via photospheric-convection•driven slow tether-cutting reconnection of the legs of the sheared core field, low above the interior PIL, as proposed by van Ballegooijen & Martens (1989) and Moore & Roumeliotis (1992). The production of this eruption is a (perhaps rare) counterexample to solar eruptions that result from external collisional shearing between opposite polarities from two distinct emerging and/or emerged bipoles (Chintzoglou et al. 2019).

Adams, M. L.↗
NASA NTRS2018

Crowd-Sourced Radio Science at Marshall Space Flight Center

August 21, 2017 provided a unique opportunity to investigate the effects of the total solar eclipse on high frequency (HF) radio propagation and ionospheric variability. In Marshall Space Flight Center's partnership with the US Space and Rocket Center (USSRC) and Austin Peay State University (APSU), we engaged citizen scientists and students in an investigation of the effects of an eclipse on the mid-latitude ionosphere. Activities included fieldwork and station-based data collection of HF Amateur Radio frequency bands and VLF radio waves before, during, and after the eclipse to build a continuous record of changing propagation conditions as the moon's shadow marched across the United States. Post-eclipse radio propagation analysis provided insights into ionospheric variability due to the eclipse.

amateur radio↗
NASA NTRS2017

Effects of the 2017 Solar Eclipse on HF Radio Propagation and the D-Region Ionosphere: Citizen Science Investigation

August 21, 2017 provided a unique opportunity to investigate the effects of the total solar eclipse on high frequency (HF) radio propagation and ionospheric variability. In Marshall Space Flight Center's partnership with the US Space and Rocket Center (USSRC) and Austin Peay State University (APSU), we engaged students and citizen scientists in an investigation of the eclipse effects on the mid-latitude ionosphere. Activities included implementing and configuring software, monitoring the HF Amateur Radio frequency bands and collecting radio transmission data on days before, the day of, and days after the eclipse to build a continuous record of changing propagation conditions as the moon's shadow marched across the United States. Post-eclipse radio propagation analysis provided insights into ionospheric variability due to the eclipse. We report on results, interpretation, and conclusions of these investigations.

Radio Propagatio↗
NASA NTRS2015

More Macrospicule Jets in On-Disk Coronal Holes

We examine the magnetic structure and dynamics of multiple jets found in coronal holes close to or on disk center. All data are from the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI) of the Solar Dynamics Observatory (SDO). We report on observations of about ten jets in an equatorial coronal hole spanning 2011 February 27 and 28. We show the evolution of these jets in AIA 193 A, examine the magnetic field configuration and flux changes in the jet area, and discuss the probable trigger mechanism of these events. We reported on another jet in this same coronal hole on 2011 February 27, (is) approximately 13:04 UT (Adams et al 2014, ApJ, 783: 11). That jet is a previously-unrecognized variety of blowout jet, in which the base-edge bright point is a miniature filament-eruption flare arcade made by internal reconnection of the legs of the erupting field. In contrast, in the presently-accepted 'standard' picture for blowout jets, the base-edge bright point is made by interchange reconnection of initially-closed erupting jet-base field with ambient open field. This poster presents further evidence of the production of the base-edge bright point in blowout jets by internal reconnection. Our observations suggest that most of the bigger and brighter EUV jets in coronal holes are blowout jets of the new-found variety.

jets↗
NASA NTRS2014

Macrospicule Jets in On-Disk Coronal Holes

We examine the magnetic structure and dynamics of multiple jets found in coronal holes close to or on disk center. All data are from the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI) of the Solar Dynamics Observatory (SDO). We report on observations of six jets in an equatorial coronal hole spanning 2011 February 27 and 28. We show the evolution of these jets in AIA 193 A, examine the magnetic field configuration, and postulate the probable trigger mechanism of these events. We recently reported on another jet in the same coronal hole on 2011 February 27, approximately 13:04 Universal Time (Adams et al 2014, Astrophysical Journal, 783: 11); this jet is a previously-unrecognized variety of blowout jet. In this variety, the reconnection bright point is not made by interchange reconnection of initially-closed erupting field in the base of the jet with ambient open field. Instead, there is a miniature filament-eruption flare arcade made by internal reconnection of the legs of the erupting field.

macrospicule jets coronal holes↗
NASA NTRS2010

Automatic Identification of Solar X-Ray Bright Points in Hinode X-Ray Data

We have automated a method that is used to find point sources in Chandra X-ray telescope data, to identify solar bright points in Hinode X-ray data. This tool, called lextrct, first identifies candidate sources that are brighter than the surrounding background. The algorithm also allows selected pixels to be excluded from the source-finding, thus allowing saturated pixels (from flares and/or active regions) to be ignored. We then use lextrct to fit the sources to two-dimensional, elliptical Gaussians. The size and orientation give an approximation of the shape of the bright points. We are in the process of analyzing observations through the Al_poly filter with a four-second exposure time, to obtain a catalogue of bright points, which will include their sizes, lifetimes, intensities, and position on the solar disk

Adams, M. L.↗
NASA NTRS2008

ART: Surveying the Local Universe at 2-11 keV

The Astronomical Rontgen Telescope (ART) is a medium-energy x-ray telescope system proposed for the Russian-led mission Spectrum Rontgen-Gamma (SRG). Optimized for performance over the 2-11-keV band, ART complements the softer response of the SRG prime instrument-the German eROSITA x-ray telescope system. The anticipated number of ART detections is 50,000-with 1,000 heavily-obscured (N(sub H)> 3x10(exp 23)/sq cm) AGN-in the SRG 4-year all-sky survey, plus a comparable number in deeper wide-field (500 deg(sup 2) total) surveys. ART's surveys will provide a minimally-biased, nearly-complete census of the local Universe in the medium-energy x-ray band (including Fe-K lines), at CCD spectral resolution. During long (approx.100-ks) pointed observations, ART can obtain statistically significant spectral data up to about 15 keY for bright sources and medium-energy x-ray continuum and Fe-K-line spectra of AGN detected with the contemporaneous NuSTAR hard-x-ray mission.

O'Dell, S. L.↗
NASA NTRS2005

NASA Celebrates the World Year of Physics

Celebrating the World Year of Physics presents NASA with an opportunity to inform educators of the importance of physics in our everyday lives. indeed, almost all NASA programs fake advantage of physical concepts in some fashion. Special programs throughout the year, affiliated with the World Year of Physics, are identifed to inform and inspire educators, students, and the general public. We will discuss these programs in detail and outline how educators may become more involved.

Adams, M. L.↗
NASA NTRS2003

NASA's Space Science Programming Possibilities for Planetaria

The relationship between NASA and the planetarium community is an important one. Indeed, NASA's Office of Space Science has invested in a study of the Space Science Media Needs of Science Center Professionals. Some of the findings indicate a need for exposure to space science researchers, workshops for museum educators, 'canned' programs, and access to a speakers bureau. We will discuss some of the programs of NASA's Sun-Earth Connection Education Forum, distribute sample multimedia products, explain the role of NASA's Educator Resource Center, and review our contributions to NASA's Education and Public Outreach effort.

Adams, M. L.↗
NASA NTRS2003

Using the Chandra Project to Communicate with Underdeveloped Constituencies

We have instituted a program whose goal is to better communicate astronomy among students selected from an economically underprivileged area of Huntsville, Alabama. To achieve this goal, six local teachers were trained as astronomy teacher resource agents. These teachers were teamed with six scientists; the teams presented materials for 29 teachers, mostly from the Southeastern United States Topics included the electromagnetic spectrum, X-ray optics, gratings and spectroscopy, supernovae (and remnants), black holes, and the tools and techniques to analyze Chandra X-ray data. Beginning in September our teacher-scientist teams, in collaboration with the Huntsville Housting Authority, will present programs to specially selected students at the rate of one or two per month, until April 2004. These young people will be mentored and encouraged to develop a research project. Students, which complete a project by April 2, will be paid for their work.

Adams, M. L.↗
NASA NTRS2002

The Sun: Our Nearest Star

We have in our celestial backyard, a prime example of a variable star. The Sun, long thought to be "perfect" and unvarying, began to reveal its cycles in the early 1600s as Galileo Galilei and Christoph Scheiner used a telescope to study sunspots. For the past four hundred years, scientists have accumulated data, showing a magnetic cycle that repeats, on average, every eleven (or twenty-two) years. In addition, modern satellites have shown that the energy output at radio and x-ray wavelengths also varies with this cycle. This talk will showcase the Sun as a star and discuss how solar studies may be used to understand other stars.

Adams, M. L.↗
NASA NTRS2002

NASA/MSFC/NSSTC Science Communication Roundtable

The Science Directorate at Marshall Space Flight Center (MSFC) conducts a diverse program of Internet-based science communication through a Science Roundtable process. The Roundtable includes active researchers, writers, NASA public relations staff, educators, and administrators. The Science@NASA award-winning family of Web sites features science, mathematics, and space news to inform, involve, and inspire students and the public about science. We describe here the process of producing stories, results from research to understand the science communication process, and we highlight each member of our Web family.

Adams, M. L.↗
NASA NTRS2001

Marshall Space Flight Center's Tower Vector Magnetograph: Upgrades, Hardware, and Operations for the HESSI Mission

The Marshall Space Flight Center's (MSFC) solar group announces the successful upgrade of our tower vector magnetograph. In operation since 1973, the last major alterations to the system (which includes telescope, filter, polarizing optics, camera, and data acquisition computer) were made in 1982, when we upgraded from an SEC Vidicon camera to a CCD. In 1985, other changes were made which increased the field-of-view from 5 x 5 arc min (2.4 arc sec per pixel) to 6 x 6 arc min with a resolution of 2.81 arc sec. In 1989, the Apollo Telescope Mount H-alpha telescope was coaligned with the optics of the magnetograph. The most recent upgrades (year 2000), funded to support the High Energy Solar Spectroscopic Imager (HESSI) mission, have resulted in a pixel size of 0.64 arc sec over a 7 x 5.2 arc min field-of-view (binning 1x1). This poster describes the physical characteristics of the new system and compares spatial resolution, timing, and versatility with the old system. Finally, we provide a description of our Internet web site, which includes images of our most recent observations, and links to our data archives, as well as the history of magnetography at MSFC and education outreach pages.

Adams, M. L.↗
NASA NTRS2001

Lessons Learned from Real-Time, Event-Based Internet Science Communications

For the last several years the Science Directorate at Marshall Space Flight Center has carried out a diverse program of Internet-based science communication. The Directorate's Science Roundtable includes active researchers, NASA public relations, educators, and administrators. The Science@NASA award-winning family of Web sites features science, mathematics, and space news. The program includes extended stories about NASA science, a curriculum resource for teachers tied to national education standards, on-line activities for students, and webcasts of real-time events. The focus of sharing science activities in real-time has been to involve and excite students and the public about science. Events have involved meteor showers, solar eclipses, natural very low frequency radio emissions, and amateur balloon flights. In some cases, broadcasts accommodate active feedback and questions from Internet participants. Through these projects a pattern has emerged in the level of interest or popularity with the public. The pattern differentiates projects that include science from those that do not, All real-time, event-based Internet activities have captured public interest at a level not achieved through science stories or educator resource material exclusively. The worst event-based activity attracted more interest than the best written science story. One truly rewarding lesson learned through these projects is that the public recognizes the importance and excitement of being part of scientific discovery. Flying a camera to 100,000 feet altitude isn't as interesting to the public as searching for viable life-forms at these oxygen-poor altitudes. The details of these real-time, event-based projects and lessons learned will be discussed.

Phillips, T.↗
NASA NTRS1999

Education and Public Outreach to Support the HESSI Mission: Raising Public Awareness

The current upswing in solar activity bodies well for accomplishing the goals of the upcoming HESSI mission. The solar community is making good use of the increased activity through coordinated observations, both in space and on the ground. Ground-based measurements will provide crucial context observations and complementary measurements of the high-energy p,,ocesses which HESSI will observe; vector magnetographs will provide information on the morphology and strength of active region magnetic fields. At the time of the launch of HESSI, we will provide scientific data to the community with the MSFC vector magnetograph and will use the facilities to enhance the educational experience of the local community. In the meantime, to raise public consciousness about the solar cycle and to prepare for HESSI observations, we have prepared lesson plans and activities which are currently being distributed via the internet. Further, to inform the educational community about our activities, our teacher partners disseminate the information by attending teacher conferences. This poster will review what we have already accomplished and what we plan for the next, few pre-launch months.

Adams, M. L.↗
NASA NTRS1991

Engine dynamic analysis with general nonlinear finite element codes

A general engine dynamic analysis as a standard design study computational tool is described for the prediction and understanding of complex engine dynamic behavior. Improved definition of engine dynamic response provides valuable information and insights leading to reduced maintenance and overhaul costs on existing engine configurations. Application of advanced engine dynamic simulation methods provides a considerable cost reduction in the development of new engine designs by eliminating some of the trial and error process done with engine hardware development.

Adams, M. L.↗
NASA NTRS1989

A seal test facility for the measurement of isotropic and anisotropic linear rotordynamic characteristics

A new seal test facility for measuring high-pressure seal rotor-dynamic characteristics has recently been made operational at Case Western Reserve University (CWRU). This work is being sponsored by the Electric Power Research Institute (EPRI). The fundamental concept embodied in this test apparatus is a double-spool-shaft spindle which permits independent control over the spin speed and the frequency of an adjustable circular vibration orbit for both forward and backward whirl. Also, the static eccentricity between the rotating and non-rotating test seal parts is easily adjustable to desired values. By accurately measuring both dynamic radial displacement and dynamic radial force signals, over a wide range of circular orbit frequency, one is able to solve for the full linear-anisotropic model's 12 coefficients rather than the 6 coefficients of the more restrictive isotropic linear model. Of course, one may also impose the isotropic assumption in reducing test data, thereby providing a valid qualification of which seal configurations are well represented by the isotropic model and which are not. In fact, as argued in reference (1), the requirement for maintaining a symmetric total system mass matrix means that the resulting isotropic model needs 5 coefficients and the anisotropic model needs 11 coefficients.

Adams, M. L.↗