By: Janet Oputa and Jennifer Henry – EclipseMob Communications and Outreach Assistants
On August 21, 2017, the sky will darken over parts of North America as the moon moves between the Earth and the sun to block the sun.
While many people will be observing this fantastic phenomenon using special viewers, amateur radio enthusiasts and others like yourself will be observing the phenomenon using radio waves. (Don’t worry, you can watch it with your viewer too!).
Many people have heard of a solar eclipse, but some don’t understand what it is or how it can impact communication systems. EclipseMob is conducting educational webinars to provide interested participants with a chance to learn about the solar eclipse and understand the purpose of this experiment. Participants also have the opportunity to learn how to build their own receivers that will monitor radio wave signals during the solar eclipse. This is a fun chance for those interested in science to unite and partake in the largest-ever low-frequency radio wave propagation experiment!
What are we trying to do?
The crowdsourcing effort, EclipseMob, is collecting radio signals before, during and after the solar eclipse that will occur over North America on August 21, 2017 to study the effect of sunlight on the ionosphere. One of these signals will be transmitted from the WWVB radio station in Colorado and one from a Navy transmitter in central California to study the effect of sunlight on the ionosphere. Crowdsourcing allows us to collect signals from locations all over the U.S. or even further, if opportunity arises. We need information of radio wave propagation from spatially diverse geographic locations and that’s why we need your help! When you build the receiver, we will want you to set it up and collect the data during the three phases of data collection (before, during and after the solar eclipse) so we can see what changes are happening to the radio wave propagation and in turn try to understand how the ionosphere changes, as the moon passes between the Earth and the Sun.
There’s still a lot we don’t know about the ionosphere and how events like the eclipse impact radio wave and ionosphere behavior. The ionosphere is the layer of the Earth’s atmosphere that contains a high concentration of ions and free electrons and is able to refract radio waves. It lies above the mesosphere and extends from about 50 to 600 miles (80 to 1,000 km) above the Earth’s surface. The effect of the solar eclipse was first collected by William Henry Eccles on April 17, 1912 using a receiver of approximately 54.545kHz frequency and a wavelength of 5,500 meters. It was collected later for the same eclipse in France and Denmark using the transmitter at the Eiffel Tower in Paris. The transmitter had a frequency of 115kHz. EclipseMob aims to solve the problem highlighted in these first studies and address the errors reported in early crowdsource attempts. EclipseMob is utilizing crowdsourcing to collect radio wave signals at locations all over the United States so we can study how the signals are affected as they travel along different paths. We want to take advantage of the fact that technology and crowdsourcing have advanced. EclipseMob hopes to have numerous people around the globe participate in this project so that we can conduct one of the largest low-frequency radio wave propagation experiments. Conducting a large experiment like this will help us to collect more data, and properly analyze and report on these signals from the ionosphere. This is important because disturbances in the ionosphere can cause further issues with communication around the globe. These issues can cause possible disruption to GPS signals and emergency communications that utilize the ionosphere when cell towers are down during instances such as hurricanes or other natural disasters.
Who’s doing it?
People just like you! Anyone can build a receiver, and you don’t have to be in the path of totality to participate. Data is needed from all over North America. Educational and community groups can even get a kit for free (see Eclipsemob.org)!
This project was started by Extra Class Radio Amateur Bill Liles and professors Laura Lukes, Jill Nelson, and K.C. Kerby-Patel. Their roles are listed below:
Bill Liles is an Extra Class Radio Amateur who has a life-long interest in understanding radiowave propagation and antennas. He is a member of the Institute of Electrical and Electronics Engineers Antenna and Propagation Society History Committee.
Laura Lukes is the Assistant Director of the Center for Teaching and Faculty Excellence and an Affiliate Assistant Professor in Atmospheric, Oceanic, & Earth Sciences at George Mason University. She is a co-leader of the EclipseMob Education & Outreach (E&O) team. E&O is dedicated to developing activities and resources for educators that meet the Next Generation Science Standards and disseminating project information to get folks involved in this once-in-a-lifetime experience.
Jill Nelson is an Associate Professor in the Department of Electrical and Computer Engineering at George Mason University. Dr. Nelson’s research focus is in statistical signal processing, specifically detection and estimation and machine learning for applications in surveillance and in physical layer communications. With Laura Lukes, she leads the EclipseMob efforts at George Mason.
K.C. Kerby-Patel is an Assistant Professor in the Engineering Department at the University of Massachusetts Boston, where her research focuses on applied electromagnetics. Her current research includes high impedance surfaces, low profile antennas, crowdsourced measurement of LF skywave propagation, and link signature keying. Dr. Kerby-Patel directs EclipseMob’s hardware team.
And now, you can join them too!
How can you get involved?
EclipseMob offers webinars in partnership with Geological Society of America on “Understanding eclipses, radio waves, and the ionosphere” and “Making your receiver system to participate in citizen science STEM research during the 2017 Solar Eclipse”. The upcoming webinar is on the April 29, 2017. In order to register for these webinars, please visit eclipsemob.org. The website also gives information as to how you could order kits to build your own receiver and antenna. You can also contact Dr. K.C. Kerby-Patel for more information on this.
After you have built your receiver, you can connect it to your smartphone or laptop and collect data before, during and after the solar eclipse on August 21, 2017. You can then upload the data collected to the EclipseMob website! We’ll be sharing the results in the fall.
Many thanks for sharing the knowledge. “Frequency” and “Time Period” are the fundamental entities in this vast limitless universe.
As the date of the August 21 eclipse draws near, keep this important safety information in mind: You MUST use special eclipse safety glasses to view a partial eclipse and the partial phases of a total eclipse. To do otherwise is risking permanent eye damage and even blindness. The ONLY time it’s safe to look at a TOTAL eclipse without proper eye protection is during the very brief period of totality when the Sun is 100 percent blocked by the Moon. If you’re in a location where the eclipse won’t be total, there is NEVER a time when it’s safe to look with unprotected eyes. NEVER attempt to view an eclipse with an optical device (camera, binoculars, telescope) that doesn’t have a specially designed solar filter that fits snugly on the front end (the Sun side) of the device. Additionally, never attempt to view an eclipse with an optical device while wearing eclipse glasses; the focused light will destroy the glasses and enter and damage your eyes.