The newsletter of NASA's Radio JOVE Project"Solar and Planetary Radio Astronomy for Schools"
The newsletter of NASA's Radio JOVE Project
Photonics Leaders II (PL2) is a hybrid science and information technology program for rising tenth and eleventh grade students from across North Carolina. Students study the physics of light and its applications. Over the course of two years, students participate in 340 hours of investigations, face-to-face instruction, virtual meetings, and internships focused on electronics, mathematics, optics, and laser technology. Upon successful completion of the program requirements, a stipend of $2400 is awarded to each student. Ninety-seven percent of students plan to pursue higher education and STEM related careers (BWF Survey, 2011).
During the summer of 2011, students investigated the power of light and its applications in astronomy for four weeks. They spent the first week building the NASA Radio JOVE receiver and antenna system to observe solar bursts and the interaction between Jupiter and its moon Io at the Pisgah Astronomical Research Institute (PARI). They communicated with researchers affiliated with NASA's Radio JOVE program while building their instruments and learned about the archived data repository, and Radio-SkyPipe software. Upon their return from PARI, students plunged into learning the science behind the Radio JOVE receivers, how to erect the instrument, and developing research plans related to the technology.
At home, they performed their pilot investigations using either real-time or archived solar flare data. To conclude their research experiences, students presented their PARI-inspired research projects at the Photonics Leaders II Summer Symposium, held at the McKimmon Center at North Carolina State University. Twenty-seven students were judged by scientists, engineers, and technology leaders from industry and academia on these categories: originality, creativity, scientific thought and understanding; organization and completeness; effort and motivation; and clarity. Medals were awarded to the following students for their scientific work.
|
Award |
Student |
Project Title |
|
Gold |
Orhun Bozkurt |
Difference in Radiation Absorbed from the Sun and Jupiter |
|
|
Arjun Raghavan |
A Measure of the Recessional Velocity and Doppler Red-shift of Cygnus A at 1420 MHz |
|
Silver |
Jordan Dunne |
The Effects of Household Appliance Interference on Radio Jove Observations |
|
|
Angella Mahasi |
Comparison of Temperatures of Data Set off of Radio Jove Archive Between Two Regions in the United States |
|
Bronze |
Arun Ganesh |
Faking Solar Flares |
|
|
Rachel Mazur |
Type III vs. Type IV Solar Bursts |
In three years, the program has served 67 students (47% African-American, 9% Hispanic, 2% Native American, 12% Asian, 23% Caucasians, and 7% Other) and their parents, along with 57 teachers from across North Carolina, representing 26 rural and urban counties. The National Science Foundation fully sponsors the Innovative Technology Experiences for Students and Teachers (ITEST) PL2 program housed at The Science House within the College of Physical and Mathematical Sciences at North Carolina State University.
In His Name
When I look back in time I find myself always curious and interested in sciences. I was 10 when I first became familiar with electronics. In middle school I became interested in astronomy also especially after the event of the Venus transit. At 14 I started seeking information on radio astronomy and the next year in high school I was finally able to access the internet. I did a lot of searching about radio astronomy especially on the topic of Jupiter so I soon found Radio JOVE, its manuals and Richard Flagg as well!
That was a wonderful time in my life. I had an opportunity to participate in an astronomy Olympiad and later two robotic competitions. This background made me able to continue radio astronomy as well. So it was the summer of my 2nd school year when I was 16, when I started radio astronomy. I traveled to Tehran to buy components of the Jove 1.1 receiver but unfortunately I couldn’t find a few important parts. I decided to make a receiver with some stages different from the original Jove 1.1 receiver. So I finally replaced a BF 256 instead of J310 and I added another RF filter stage and a RF low noise MAR amplifier also. I used a crystal oscillator based mixer instead of a varicap based circuit and I changed the LM387 and transistor AF amplifier with a common op-amp amplifier with LM386 at the last stage. Due to the crystal based mixer I could easily change the crystal so it was capable of tuning between 15 and 30 MHz. After 100 hours of works my system seemed to work. But the only trouble was the quiet year of sun. I had a simple dipole on my roof inside the city so I only had the chance to observe the milky way and the sun. The sun seemed always quiet that summer so I could only hear the milky way, lightning, power arcing and motorcycle noises. I never forgot my many hours of observations seeking the sun but always nothing.
Finally I obtained the hard to find parts which made it possible to build an exact copy of the Jove receiver. I started building during the summer before college, I was then 18 years old. I tried hard. I didn’t have the printed circuit board, but I used a matrix dot board instead and copied Jove's layout on it. When I finished installing the parts I started to test but there seemed some bad trouble. The whistle tone was always too low. I made a lot of effort in the last days before the university started but to no effect. It was all left until next summer. I worked hard again on it to troubleshoot the problem. I followed any guess I could try but it was lots of work and no good results. I remember nights to mornings working on my system without any instruments in hand.
Finally last spring, after my second year of college, again it was time to work on my system. One of my friends called me and said that he is able to borrow a spectrum analyzer for a few days and I asked him to let me use it to trouble shoot the system. We started with monitoring the radio band around the system and Woops! We found that the system was tuned at 60 Mhz all these 2 years, the third harmonic created by the oscillator! We fixed that and now wow, the whistle is so loud it can deafen me! He shouted to me "Be aware, without instruments especially a spectrum analyzer you are blind in the RF". Oh, I'll never forgot that afternoon and how surprised I was after spending two years on this project. Over the next few days I installed it in a box and now it is ready to help me start observing a new world. I'm so happy that it came out so well and I'm happy being a Jove participant.
A problem I'm having now is the antenna. I only have a small roof inside the city and that is not good. At the end I would like to give my warmest wishes to Dick Flagg, for being such a good friend, teacher and guide for this little student. I believe it will be so enjoyable and informative to listen to the sky, with my own system.
Radio Jove MU is the Radio Jove project under the Department of Physics, Mekelle University, which is installed at Mekelle University near the Mekelle University Metrological station. Its main purpose is to collect radio signals from Jupiter and the sun at 20.1 MHz frequency and also to share and compare its data with other observers all over the world.
The Ethio-Jove (Radio Jove in Ethiopia) project is started to provide teachers and students with an opportunity to do hands-on radio astronomy and to introduce them to space physics in general.
Rooted in the above goals Ethio-Jove installed its radio antennas at different areas. One is at Mekelle, Mekelle University (Latitude 13o29’ N, Longitude 39o28’ E) and four in Oromia, Asella high schools (Latitude 7o57’ N, Longitude 39o7’ E).
The Radio Jove MU group went to Asella and made a seminar presentation. The main objectives of the seminar was to present the basics of the project, share experiences, to make connection (sharing real data) between Mekelle University’s and Asella’s Jove stations and to share and serve our data with observers all over the world. The presentation was done by Kibrom Ebuy and Samuel Fetwi. The Principals of Chilalo secondary school and Asella preparatory school were very happy by the seminar and promised the Mekelle Radio Jove group to share their data. Physics teachers and science club students of Asella preparatory school were among the many who attended in the seminar.
Ethio-Jove has already written an introduction letter to the community and introduced the project, prepared a data collection manual and started data collection. The Mekelle University radio Jove group collected some solar radio bursts using its 15ft, EW-in phase, and dual dipole antenna. In the next few years Ethio-Jove is planning to collect data in client and server modes so that we can compare our data and serve to others. In the coming seasons undergraduate students are planning to do their bachelor thesis on the project.
We are pleased to use this opportunity to give our special thanks to Wanda Diaz for her amazing help from the beginning of the project, Dr. Abebe Kebede, Dr. Alem Mebrahtu, Dr. Jim Theiman, Dr. Fields, Chuck Higgins and all the Radio Jove group. We hope we will be the best data deliverers to the Radio Jove Group and researchers all over the world as it plays a tremendous role in developing astronomy and space science in Ethiopia.
Chuck Higgins and Jim Thieman gave another workshop for K-12 teachers this year in coordination with the Goldstone Apple Valley Radio Telescope (GAVRT) program (http://www.lewiscenter.org/gavrt/). In part these teacher education workshops help with Juno Mission education and public outreach. The week of July18, 2011 was spent working with 13 NASA Explorer School teachers from around the country on the GAVRT and Radio Jove programs. They come away with a whole range of curriculum activities and classroom support materials, as well as the ability to use the GAVRT and Radio Jove equipment with their classes. Teachers also get ongoing support for their classes and schools so they can use the materials each school year.
Teacher workshops take place at the Lewis Center for Educational Research (LCER) and are open to all K-14 educators, as well as Informal educators. New opportunities for Online training are coming soon. For details see this website: http://www.lewiscenter.org/gavrt/opportunities.php.
Over the years I’ve heard quite a few solar bursts. It seemed like most of them occurred in the morning hours. I decided to check and see if that perception was correct.
Radio spectrogram images are saved every 10 minutes at Windward Community College Radio Observatory (WCCRO).
The antenna is an 18-30 MHz log-periodic aimed due south at a high elevation angle. Since the antenna is aimed due south it should not favor morning or afternoon activity.
Every spectrograph image from August 1 thru September 11, 2011 was analyzed to determine which images contained solar activity (over 3000 daytime spectrograph images). If there was any solar activity in the 10 minute long spectrogram then the time of the image was noted. These times were then sorted into hour long bins, representing local time. For example the spectrogram above would carry a count of 1 event and be placed in the bin for 11-12 Hawaii Standard Time. (Hawaii is 10 hours behind UTC).
Two hundred spectrograms were found to contain solar bursts. The following plot shows the occurrence of those bursts with local time.
At this time of year solar transit occurs near 12:30 HST. From the above plot we see that approximately 75% of the spectrograms containing solar bursts were recorded before solar transit while only 25% occurred after.
Why aren’t bursts as frequent in the afternoon as in the morning? The cause is likely the Earth’s ionosphere. The ionosphere starts out relatively transparent at dawn and becomes increasingly opaque during the day. The increase in opacity causes increased absorption and refraction. In the morning hours the solar bursts pass through the ionosphere with relative ease, but as the day wears on the opacity increases and refraction of some solar signals back out into space increases. Those bursts that are not refracted completely suffer increased attenuation passing through the thicker ionosphere.
In summary it appears that solar activity is most likely to be received in the late morning, at least with an antenna whose broad beaming pattern is centered on solar transit.
On August 4, 2011, at 0358 UTC, while the sun was overhead in the South China Sea, an M9 solar flare occurred. Jove observers around the world detected this event. Interestingly, several observers were “in the dark” at that time, yet they still received the solar burst even though it was during their night time.
Observers reporting this event on the Jove listserve include the following:
The station locations and their records are seen below. The night time portion of the earth, when the burst occurred, is darkened. The three continental US stations and the UK station were all in darkness. It was just after dawn in Germany while the Hawaii and Alaska stations were observing the sun in late afternoon. Each record spans approximately 6 minutes.
Who says the sun doesn’t shine at night?
You may now submit Jupiter and solar observation data directly to the Radio Jove Archive from the Radio-SkyPipe (RSP) data collection program. The latest version of RSP has new features that allow you to easily mark active areas on your charts and send these chart segments along with corresponding wav (sound) and text files to the archive. Just a few clicks of the mouse will accomplish what formerly required significant effort. You can set up different profiles for your various equipment configurations. Type your information once and never again. We are encouraging more observers to record sound with their observations using the RSP wav recorder. New tools in the program make this easier than ever. Attended and unattended observations are supported. See the help links below for more information.
Read about the RSP features that support archive submission here.
Watch a video of the process here.
Here is an un-narrated video of the submission process.
You may download the needed update for your Radio-SkyPipe software
( version 2.3.19 ) at:
http://radiosky.com/skypipe/skypipe_2_3_19_update.exe
This past summer we had the privilege of working with Ajamu Abdullah, an undergraduate student at Howard University in Washington D.C. Ajamu studied data retrieved from the Radio Jove archive and also assisted in the movement of the Radio Jove dual dipoles from the Building 26 site at Goddard Space Flight Center to a new location at the Goddard Geophysical and Astronomical Observatory (GGAO) area. Ajamu is back in school now and we thank him for his help and wish him well in his continued studies for a physics degree.
In the never ending quest for reduced interference and better reception of Jovian emissions, I have installed a four‐dipole array. The SuperJove Double Dual Dipole (SJD3 for short) array is basically two almost-standard Jove arrays connected together. They're not completely standard because I used 50 ohm coax in lieu of the 75 ohm coax of the standard Jove array.
The dipole wires run east to west. Each Jove array is separated by 40 feet in the north‐south direction. Given Jupiter’s high elevation, almost 80° at transit for my latitude of 30° N, I phased the array for a beam centerline elevation of 78° according to the EZNEC model.
According to the model, the directivity gain is 11 dBi and the primary beam is a thin, fan‐shaped affair running east to west. This is ideal for Jupiter observation. I can say without hesitation that the antenna has allowed me to observe a greater number of weak non‐Io events, and greater detail (modulation lanes) in the stronger events, than I was able to see with my standard Jove array.
Elements are supported by military surplus green fiberglass tent poles, three poles per mast, placing the elements 10 feet above the ground. Guy lines are military surplus 3/16 inch black polyester rope. With these materials, the array is quite stealthy and visually unobtrusive. All fixed ropes are tied with bowline knots; the adjustable guy lines are tied with trucker’s hitches.
Here is a photo essay of the development and construction.
I had originally designed the SuperJove array in EZNEC using some phasing cable lengths that I selected through trial and error to produce a good beam pattern. However, I have since learned the time‐delay method—i.e., the right way—of phasing dipoles together. In the future, the elements will be evenly spaced instead of having an odd gap in the middle. There are also tricks to lower the side lobes that I wish to try. That will be covered in Part 2 of the SuperJove array.
I have been involved with the Radio JOVE program for many years. Off and on, at various locations, I’ve been blessed with a quiet receiver and cursed with the dreaded power line noise problem.
I set up and began my Radio JOVE system at my current location some three years ago. Typical to some installations, I had intermittent bouts of power line noise. I was able to identify some potential power poles that might be causing the problem. I went online to my power company web site and found a place to send an email if I had any problems. I sent an email to the power company, explained my problems and listed the power poles I felt needed investigation and possibly remediation. I received an automated email reply saying that the email in question would be forwarded to the appropriate office and that I would hear something from them soon. After about two months, I had heard nothing from the power company.
As time went on, the time between bouts got shorter and shorter. Finally, it became nearly constant. Again, I went online to my power company’s web site and send an email about the problem and said that I’d not heard anything back from then on the first email. And again, I received an automated email reply saying that the email outlining my problem would be forwarded to the appropriate office and that I would hear something from them soon. Another month or so passed and still no answer from the power company.
I’ve dealt with power companies in the past, and I’m reminded of a line in the movie, Cool Hand Luke. “What we have here is a failure to communicate.”
It was time to go straight to the person in charge. So, my third attempt was to send a letter addressed to the power company with the line ATT: RFI Problems. (RFI is radio frequency interference). Once again I outlined the problem I was dealing with and added that I would like to hear from them and casually mentioned that in the state of Pennsylvania, all power companies were governed by the Public Utility Commission. At least in this state, that carries some weight. Some weeks went by and still I heard nothing.
I happened to be home one afternoon and I heard the “beep, beep, beep” of a utility vehicle backing up. When I went to investigate, who could it be but the power company! I went out and cordially greeted them and told them that I was glad that they had finally come in response to my requests. (Here’s where the “failure to communicate” comes in). The supervisor of the crew told me that this is the third time they’d been out, but wasn’t able to find the problem. Being intermittent, they happed to be there on the days it was quiet. If the power company had told me that the crews would be out on a given day and time, I’d have made arrangements to meet them.
Again, they were not able to locate the problem, but they were going to go up the pole nearest my antennas and check all the connections. While they were doing that, I went inside the house and brought out my 2 meter hand held receiver which just happens to have an AM band that goes into the 118 MHz portion of the band. Using it and a three element hand-held Yagi, I walked the supervisor around and pinpointed to his satisfaction the problem. Their equipment was not capable of this and so dismissed the problem on the first two visits. We didn’t identify just one pole; we found at least 4. One of the poles in question, it turns out, had a transformer fire about a year earlier and had reduced the top of the pole to charcoal, affecting all the insulators at the top.
They worked for 4 days, and replaced one 60 foot pole; replaced at least a dozen bad insulators and fixed the ground wires on at least two of the poles that I saw. They were nice, friendly and helpful. And when they were done, 90% of the problems went away. At least all the serious ones are gone. I still have the occasional buzz of line noise, but it’s intermittent and it’s something I can live with right now. I sent a thank you letter to the head supervisor at the power company, and was able to thank personally the supervisor of the crew that worked so hard to find and solve my problem.
I guess the moral to this story is that if at first you don’t succeed, keep trying. If you don’t hear from the power company, call them. Find out if they’ve sent any crews out and if they did, what was discovered. If they tell you a crew is scheduled for a given date and time, try to be there. If they tell you the crew was already there, ask them what they found. Most of these crews are ok and will try to work with you if they understand the problem. If you don’t have a 2 meter hand held radio, try a simple AM hand held radio. Chances are you’ll hear it on that as well. It was so bad here you could even hear it on FM radios! Get the number off the pole you think is the problem and give them that information. You can also build a hand held loop antenna for 20 MHz and hook your JOVE receiver to it and see if you can’t pinpoint down the source with that. There are many ways to identify a bad power pole. If you get a hold of some night vision gear, go out at night and look at the poles. They’ll stand out like a sore thumb if there is any arcing going on. Even a pair of binoculars will reveal an arc at night if it’s big enough. The point is, don’t give up. It’s their job to identify and fix these problems. In most cases, working with them will get it fixed.
Other Resources:
Text:
The ARRL RFI Book: Practical Cures for Radio Frequency Interference by Mike Gruber and David Pingree (Apr 1, 2007)
Websites:
http://www.arrl.org/radio-frequency-interference-rfi
http://www.arrl.org/products-and-other-resources
http://www.arrl.org/files/file/Technology/RFI%20Main%20Page/Hallas.pdf
http://www.on4ww.be/emi-rfi.html
http://www.rsgb.org/emc/i-am-experiencing-interference.php
Gergely "Gary" Forintos sends us this picture of his Jove setup in the United Arab Emirates. Gary has made what we believe to be the first reception of Jupiter signals from this region. He has previously observed Jupiter from Hungary with a homemade 4-element Yagi antenna and is now working as a flight instructor in the Emirates. Many have enjoyed Gary's videos, shot from his ultralight. An enthusiastic supporter of Jove, Gary hopes to interest local schools in radio astronomy and the Jove program.
We came across another Radio Jove team, the Project Letha Radio Astronomy Observatory in Washington State, USA. Radio Jove dipoles grace many scenic vistas on this fair planet and here's another one. Anyone know which mountain this is?
The JOVE Bulletin is published twice a year. It is a free service of the Radio JOVE Project. We hope you will find it of value. Back issues are available on the Radio JOVE Project Web site, http://radiojove.gsfc.nasa.gov/
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