Slide 1:Hello everyone, I'm Shahd Mohamed Hassan, a first-year Basic Science student at the Faculty of Education, and this is my video for the Educational Technology course. My topic is the Wow! Signal: a short, powerful radio signal from space that scientists still cannot fully explain. Let's start with what happened.
Slide 2:On August 15, 1977, a radio telescope called Big Ear, at Ohio State University in the USA, was scanning the sky and searching for signs of intelligent life. It picked up a very strong radio signal that lasted about 72 seconds, and it was never detected again. A few days later, astronomer Jerry Ehman was checking the printout and noticed this sequence: 6EQUJ5. He circled it and wrote 'Wow!', and that is how the signal got its name. An important point: this sequence is not a message. It is a code that tells us how strong the signal was.
Slide 3:So how do we read that code? The computer printed one character every 12 seconds, and each character shows how many times stronger the signal was than the background noise. Digits are small numbers, and letters continue the scale, so E is 14, Q is 26, and U is 30. Look at the curve on the chart: it rises, peaks at 30 times the background level, then falls. That shape is what we expect from a fixed source in space passing through the telescope's view as the Earth rotates. The signal was also narrowband, meaning its energy sat in a tiny range of frequencies, and it came from the direction of Sagittarius.
Slide 4:The signal's frequency was close to 1420 megahertz, and this number is special, because it is the frequency of the hydrogen line. A hydrogen atom has one proton and one electron, and both have a property called spin. When the electron flips its spin from aligned to opposite, the atom releases a tiny amount of energy as a radio wave with a wavelength of 21 centimeters. Hydrogen is the most abundant element in the universe, so scientists have long suggested that this is a natural frequency to search near. That is why a strong signal there got so much attention.
Slide 5:So what caused it? There are three main ideas. First, an extraterrestrial civilization sending a transmission, but there is no direct evidence for this. Second, a natural source, for example a cold hydrogen cloud that suddenly brightens. Third, interference from human technology, but the 2025 study found this increasingly unlikely. So far, no explanation has been proven.
Slide 6:The mystery is still being studied. After 1977, searches found nothing like it. Then in 2025, a team led by Abel Méndez at the University of Puerto Rico at Arecibo re-analyzed archival data from the original Ohio SETI project, including records that had never been published. They refined the signal's properties and found that a natural origin deserves serious consideration, but they still could not pinpoint the exact source. To conclude: the Wow! Signal is an unusual radio detection, but it is not proof of extraterrestrial life, and we need more observations to solve it. Thank you for watching.
Slide 7:These are the sources I used for this presentation.
