2024 SARA Western Conference Abstracts
Getting started in hydrogen line radio observing using
a military dipole array antenna.
Dr Andrew Martyn Thornett. (Virtual)
British Astronomical Association Radio Astronomy Group
Mapping the arms of Milky Way at 1420.405Mhz and determining the Milky Way's rotation curve has been achieved by many observers with a wide variety of instruments and antennae. The development of readily available, cheap radio equipment, excellent programs for inexperienced observers, and new beginner-friendly software, these observations are easier to achieve than ever before. This paper describes the author's journey and success in this field with the help of the SARA Scope in a Box package, a cheap commercial software defined radio, a repurposed UK military band 3 dipole array < 1m Square, and the ezRA (Easy Radio Astronomy) suite of software, from a radio-noisy urban environment in Staffordshire, England, UK, and how this has encouraged him to take up a wide range of other radio astronomy activities, and to become an advocate for radio astronomy amongst other amateurs without a radio or electronics background.
Total beginners guide to attempting to get started in hydrogen line
interferometry using very small dishes < 1m in size
Dr Andrew Martyn Thornett (Virtual)
British Astronomical Association Radio Astronomy Group
Many newcomers to the amateur radio astronomy have no background in amateur radio, electronics or engineering but do have passion and a desire to expand their horizons beyond observational astronomy and astrophotography. They are keen to explore the same kind of areas covered by professional radio observatories. Current professional observatories use interferometry to achieve larger resolutions that can be achieved with a single dish, and because many amateurs can only access smaller sized equipment, the idea of using similar techniques to achieve larger effective apertures is very enticing.
Radio astronomy forums and groups have members who successfully carry out interferometry experiments using dishes in the 3m range and often complex equipment. My aim was to build and successfully observe interferometry fringes on the Sun using cheap off the shelf components, purchased from every day consumer websites, and dishes < 1m in size, also easily sourced from similar places. As I am hoping that any success that I have with this project can be expanded to hydrogen in the Milky Way, I opted to use 1420MHz. I will describe the ups and downs and then go on to discuss my results, whether I had a degree of success, and lessons I learnt from the experience, and to what extent I think that this can be achieved by other amateurs with limited knowledge and funds.
Lunar Occultation Observation of Radio Sources
Wolfgang Herrmann (Virtual)
Astropeiler Stockert e.V.
Lunar Occultations are events, when a radio source is obscured by the moon. This can happen for radio sources which are close to the ecliptic. For any particular radio source these are rare events which can be centuries apart.
In the talk I will report on the observation of occultation events of the radio galaxy 3C273, the crab nebula and the Sagittarius A region. It will be described how the events are predicted, how the observation strategy has been developed and what the results have been.
A Novice’s Guide to Amateur Radio Astronomy
Nathan Butts
SOKY-RAD
You’ve fallen down an intellectual or engineering rabbit hole and you’re thinking about taking up radio astronomy. Excellent choice! It’s fun, it’s challenging, it’s rewarding, and most of all I’ve made lots of mistakes that you can learn from to help make your path a little bit easier (hopefully). If you’ve gotten this far in your own research, you know what radio astronomy is. In this work, we will discuss why you would you want to do radio astronomy, what to expect on your foray into RA (lessons learned and realistic expectations), its benefits over other forms of astronomy, and, importantly, how to get started on the right foot. My hope is to encourage incoming novices to be the kind of radio astronomer they want to be and to do the kind of radio astronomy they want to do.
IBT Eclipse Failure and Other Failed Observations:
A presentation of what NOT to do!
Bruce Randall NT4RT
The Itty Bitty Telescope (IBT) is a popular demonstration radio telescope. Plans to use it to show change in 12 GHz solar flux during the partial eclipse of October 14, 2023 did not go as expected. In my area of South Carolina, sun coverage was about 43%, which would show a definite effect on solar flux. I had planned to have a demonstration at a public event at the local science museum.
A shadow device is used to aim the IBT. Final aiming is done with signal strength. A few days before weather was obviously going to be cloudy, so shadow aiming devices will not work. Setting circles were fabricated so that a compass heading would allow aim calibration.
The sun’s path was too close to the Clarke belt. The IBT LNB is designed to receive satellites.
Other failed observations will also be discussed. If it can go wrong there is a good chance it will!
Paper and presentation are on how to predict problems and hopefully, fix them.
Mapping the Milky Way by Cross Section Data
Felicia Lin
About 73% of all visible mass in the universe is made of hydrogen. In other words, wherever there is visible mass significant enough to be recorded, it is almost guaranteed to contain an abundant amount of hydrogen. By simply collecting data on hydrogen in our galaxy, we can figure out the shape of our galaxy by some programming and math. The intensity of hydrogen emission tells us the amount of mass, and its velocity computed from the Doppler effect describes its relative distance from the center of the galaxy. To collect data, we maneuver the antenna across the sky to particular regions, and the data is put into a program called ezRA to produce interpretable graphs. To fully understand these graphs, in depth knowledge of how the antenna, program, and the math incorporated is very important. Background knowledge of Newtonian and electrical physics is necessary for comprehensive conclusions to be drawn on the data collected. At the end of collecting, refining, and interpreting data, we concluded that our findings are similar to what NASA had published of the spiral shape of our galaxy, with spiral arms generally matching up. What is more, we found the galaxy having a warped shape instead of being completely flat, as with many other studies done by other people.