Abstracts for 2018 SARA Western Conference, Stanford Univ, Palo Alto, CA
2018 SARA Western Conference,
Stanford Univ, Palo Alto, CA
Abstracts
Keynote Address:
RADIO ASTRONOMY PROBING
STELLAR ATMOSPHERES
Dr. Carl Heiles
Emeritus Professor of Astronomy
University of California
Berkeley, CA
In May, 2013, we used the 100-m diameter Green Bank Telescope to observe the 8.3 GHz carrier of the Messenger satellite, which was in orbit around Mercury, as they both went behind the Sun. This allowed us to see the propagation effects on the spacecraft's carrier produced by the Solar atmosphere. We saw the carrier undergo frequency shift, line width broadening, amplitude modulation, polarization rotation, and linear/circular polarization conversion, all caused by electron clouds and turbulence in the Solar atmosphere. These spacecraft signals can be strong: for 1-second integrations with the GBT, our signal/noise was much better than 10000:1.
How about other stars? So-called OH/IR stars are optically invisible because they are enclosed within an expanding molecular shell full of optically-absorbing dust. The dust re-radiates the star's energy in the infrared (IR), which pumps OH masers located in the shell and, not incidentally, allows us to detect the star---hence the moniker 'OH/IR star'. Some of these masers lie behind the star and their radiation must suffer propagation effects. These masers can be very bright, more than 100 Jy.
With the strong signal strengths and narrow bandwidths, both projects offer exciting small-dish high-tech possibilities for amateur radio astronomers, and long-term monitoring should offer unmatchable data for detecting Solar-system electron clouds (Coronal Mass Ejections traversing the Solar system, for example) and comparison of OH and IR flux densities from the highly-variable OH/IR stars.
Special Guest:
OPTICAL AND RADIO BASED SATELLITE TRACKING USING ASTROMETRICAL POSITION AND DOPPLER ANALYSIS TO DETERMINE ORBITAL ELEMENTS AND SPACECRAFT CHARACTERISTICS
Scott Tilley, VE7TIL
Roberts Creek, BC, Canada
Details will be provided of a tracking system designed to obtain both optical and radio based astrometrical and radio based Doppler characteristics of spacecraft in low Earth orbit (LEO), high Earth orbit (HEO), Geosynchronous Earth orbit (GEO) and missions around and in the vicinity of the Moon. The system consists of multiple S-band antennas mounted coaxially with various optical sensors allowing for detection and tracking of objects optically and by radio simultaneously. Radio is used primarily to enable visual tracking of targets by refining their trajectories until such time as they are constrained enough to allow for visual acquisition. Using visual acquisition the station in concert with other observers can constrain orbital details to allow for reliable tracking and orbital element generation for categorization. A description of the hardware and software used will be provided along with the operational techniques that allowed for the recovery of IMAGE [2000-13A, 26113] as well as various other missions.
ANALYSIS OF A TYPE II SOLAR RADIO BURST
OBSERVED ON 20 OCTOBER 2017
Whitham D. Reeve
Reeve Observatory
Anchorage, AK
A Type II solar radio burst was observed on 20 October 2017 near the end of the UTC day at Cohoe Radio Observatory in Alaska in circular polarization and at UNAM – Instituto de Geofísica unidad Michoacan in Mexico in linear polarization. Both stations are part of the e-Callisto solar radio spectrometer network {eCallisto}. The received burst was observed to have fundamental, harmonic and split-band characteristics in the frequency range 45 to 85 MHz. Measurements of the burst may be used to infer the speed of the associated coronal mass ejection (CME) and the coronal magnetic field.
I provide a general description of the production, propagation and characteristics of the Type II radio burst followed by a brief description of the overall solar event that produced the radio burst observed on 20 October. Next, the burst is analyzed for its frequency characteristics, estimated CME shock speed, estimated magnetic field in the radio burst area and other parameters. The methods used here demonstrate how radio data and spacecraft imagery can be used for comparison and to gain a more complete knowledge of the CME associated with a Type II radio burst. Finally, the results are discussed.
It is quite clear from the literature that there is no universal understanding or agreement on the processes that produce Type II radio bursts. The rather simple ideas and analyses put forth in this paper are based on the most commonly accepted methods and meant as a starting place for my own future investigations of solar radio phenomena.
OBSERVATIONS AND RADIO ASTRONOMY EDUCATION
STRATEGIES USING RADIO JOVE
Paula Umansky and her team
Chabot Space and Science Center
Oakland, CA
This project involves the creation and usage of Radio Jove, an educational initiative created by NASA for the purpose of teaching students and the general public about radio astronomy. Our project focuses on creating a unique approach to educating high schoolers in a non-classroom setting, with an emphasis on team collaboration and learning through hands-on experience. In addition, the data collected will be used to provide the Chabot Space and Science Center with sounds of Jupiter and the Sun, which will be used in an exhibit for the public. The results from this project will include a philosophy of outside-of-school teen education, an understanding of the functions of radio telescopes for our students, and an opportunity to educate the public about radio astronomy through the exhibit.
SITE LOCATION STUDY FOR RADIO ASTRONOMY OBSERVATORY USING MCDA AND GIS TECHNIQUES IN THE PHILIPPINES
Rizchel M. Masong and Romeric F. Pobre
De La Salle University,
Manila, Philippines
Site location study in a particular type of observatory must be considered in order to come up with desired data. This should take in to account specifically when doing radio astronomy observations. In the Philippines, radio astronomy has limited access to research since there is no constructed observatory in this kind of discipline. Through this study, it can give various choices in selecting location in constructing and performing radio astronomy observatory.
For this to materialize, the researcher identified the parameters that affect the performance of radio observations under two distinct parameters such: (a) anthropogenic factors and (b) geographic factors. Under the anthropogenic factors are the population density (1) and road network (3). On the other hand, geographic factors are the climate type (2), and topographical shielding (4). Each of these factors has shown direct correlation with the Radio Frequency Interference (RFI) based from the initial analysis through Multi-Criterion Decision Analysis (MCDA).
As a result, the researcher was able to rank 16 regions in the Philippines in which we can deploy the best radio astronomy observation site.
DETERMINATION OF APPROXIMATED
NATURAL NOISE TEMPERATURE IN
SELECTED REGIONS IN THE PHILIPPINES
Rizchel Masong and Romeric Pobre
De La Salle University,
Manila, Philippines
The construction of any antenna plays an important role especially in telecommunication. Antennas can generally acquire noise temperature present on the antenna system and in the environment in which we will call as the antenna noise temperature. This term is the temperature of a hypothetical resistor at the input of an ideal noise-free receiver that would generate the same output noise power per unit bandwidth as that at the antenna output at a specified frequency. In other words, antenna noise temperature is a parameter that describes how much noise an antenna produces in a given environment.
This temperature is not the physical temperature of the antenna. And antenna noise temperatures have contributions from natural sources such as: earth’s temperature, sun, electrical devices, radiation from outer space, and the antenna itself. The researcher attempted to determine the approximated noise temperature from natural sources that can play a huge role on the radio telescope antenna design construction. Making it possible to take an account to support the appropriate antenna designs and the regions in which the radio telescope can be built.
And by looking at the outcome, the researcher was able to calculate the naturally occurring temperature noise in each region.
ANALYSIS OF REQUIRED ZENITH OPACITY
OF RADIO ASTRONOMY OBSERVATION
IN THE PHILIPPINES
Rizchel Masong and Romeric Pobre
De La Salle University,
Manila, Philippines
Radio astronomy especially ground-based radio astronomy observation is limited to the visible and radio atmospheric windows, frequency ranges of the electromagnetic spectrum in which most radiation can reach the ground. The radio window is much wider than the visible window when plotted on logarithmic wavelength or frequency scales, so it includes a wide range of astronomical sources and emission mechanisms. This limits the observation of observation window in a particular period of time. Also, the atmosphere is not perfectly transparent at any radio frequency.
Zenith opacity is composed of neper with the ratio of a given air mass. When zenith opacity is plotted against frequency we can arrive with an opacity forecast applicable to the area of interest. Since air mass is time dependent, the air mass itself may vary to a certain period of time. Allowing the researchers to show what is the required zenith opacity of radio astronomy in the Philippines.
As a result, the researcher was able to determine the zenith opacity of radio astronomy in different regions of interest.
MARS CALLING EARTH!
Fred Starks
This paper discusses the 1924 Todd/Jenkins radio-listening experiment for signals from Mars. Although this experiment has become the source of much ridicule and doubt; at the time it was considered and authentic effort to use the new format of radio to search for signals from space.
The presentation will cover four points: 1- How the event was organized. 2- How it was conducted and what results were recorded. 3- What happened to both the recordings and the participants. 4- What lessons can be learned from this effort that are applicable to your work today.
The presentation will be supported with copies of the participants' interviews and correspondence and the captured radio-receiver recordings. Afterward, there will be a question and answer period.
A GEOGRAPHICALLY-SPACED
SYNCHRONIZED SIGNAL DETECTION SYSTEM
Skip Crilly
Green Bank Radio Observatory
Green Bank, WV
A system has been designed and implemented that makes simultaneous geographically-spaced time-and-frequency-synchronized measurements of hypothetical extraterrestrial narrowband signals in the 1405-1448 MHz band. One radio telescope is the Sixty Foot Deep Space Exploration Society Plishner Telescope in Haswell, Colorado, and the second radio telescope is the Forty Foot Telescope in Green Bank, West Virginia. A GPS-signal-locked reference oscillator and a digital back-end is used at each site to permit differential Doppler measurements to a precision of +-1.8 Hz. This presentation will describe the system, observations of simultaneous close-frequency pulses, and future plans to enhance capabilities of the system.
GALACTIC NAVIGATION POSITION DATA
USING INTERSTELLAR MEDIUM HI
VELOCITY MEASUREMENTS
Richard Russel
Deep Space Exploration Society
This paper explores the use of HI Doppler measurements as an aid to galactic navigation. Historic HI measurements of the Milky Way are used to determine the galactic rotation rate. The location of the interstellar medium producing the HI signals can then be calculated. Knowing the location of the HI signals, the HI frequency corrections can be made for a spacecraft moving between two points in the galaxy. This data can then be used to supplement optical, pulsar and other galactic navigational aids.
SUPER-SID 2018 UPDATE
Keith Payea, AG6CI
SARA SuperSID Coordinator
SuperSID is a system for receiving and analyzing VLF signals from powerful government transmitters around the world as a way to detect Sudden Ionospheric Disturbances. The primary goal of the project is to provide SuperSID systems at no cost to educators and students to encourage the study of Astronomy and Space Weather. The SuperSID project is nearing its tenth year in operation. In that time hundreds of SuperSID systems have been shipped around the world. This talk will give a brief overview of the SuperSID project, its history, its current status, and plans for the future. Results obtained during the 2017 Total Solar Eclipse in the USA will also be discussed.
SID Space Weather Monitor Participation in the
IHY/ISWI Education and Public
Outreach Programs – a 10 Year Retrospective
Deborah Scherrer,
Stanford University Solar Center
The International Heliophysical Year (IHY), 2007-8, aimed to advance our understanding of the fundamental processes that govern the Sun, Earth, and heliosphere. The IHY Education and Outreach Program was specifically dedicated to “inspiring the next generation of space and Earth scientists as well as spreading the knowledge, beauty, and relevance of our solar system to the people of the world.” The continuing International Space Weather Initiative (ISWI) extended the instrument distribution programs to “develop the scientific insight necessary to understand the science…including
instrumentation, data analysis, modeling, education, training, and public outreach.”
In the SID Space Weather Monitor project, a part of both the IHY and ISWI education programs, we deployed a network of instruments to high schools and universities around the world. These sensor monitors provided quantitative diagnostics of solar-induced ionospheric disturbances in a manner designed to give students hands-on access to real scientific data. To support the program, we instituted a series of educator training workshops to provide scientific background and to supply educators with resources to support their own programs. Workshops were given at the various IHY and ISWI summer schools and conferences.
My presentation will highlight the progress of this educational program through the IHY and ISWI, the roadblocks we faced, what partnerships we developed, the outcomes of the educator workshops, and what made the project successful.