I had a theory that it was someone walking across the field with an electronic device, like a flashlight. So I looked up the duration of the signal, size of the field, and average walking pace. It matched perfectly.
They finally traced it to people using the microwave in the break room in a very specific way. Some people liked to open the microwave door before the timer went off. The microwave stopped, of course, but there was a split second where it was still emitting while the protective cage was opened, and the energy that leaked out during those couple of ms were enough to screw with the observatory equipment.
Aliens? Nope, just some tired grad student reheating their coffee.
Not sure which is the chicken and which is the egg here.
But the observatory had either a well-shielded microwave or break room was in an adjacent building or something (they did consider "ya know, microwaves make RF emissions, and we're running a sensitive RF measurement facility here"). It was just when the door was opened that the energy emissions exceeded the design specifications. Classic human factors always find a way around your design.
Microwaves have gotten better shielding. My old one used to take out Wifi and Bluetooth standing next to it, but my current one doesn't cause problems.
The official FCC minutes from 1945 [1] indicate that publicly they were marketed for heat therapy massages not food, with a weird wink, wink that if they could get a carve out for using for medical reasons they could also sell it to the Navy for reheating food as well.
The ISM carve out came after by a couple of years in 1947 because Raytheon had got an exception for this machine, not the other way around.
The whole origin story of why this particular slot of spectrum is full of carts before horses. That water oscillation thing is a common misconception - water oscillates at much higher frequencies [2].
[1] https://www.worldradiohistory.com/Archive-FCC/FCC-Annual-Rep...
[2] https://www.sciencedirect.com/science/article/abs/pii/S01691...
Press `STOP` first, got it.
> The U.S. Environmental Protection Agency says most granite countertops are safe, adding little to a house's radon level. It depends on the rock that is used, the agency says, recommending that homeowners concerned about radon get their countertops tested."
https://www.naturalstoneinstitute.org/designprofessionals/ra...
I live in a high-radon part of the world (Appalachia), and there are so many more benefits to having an ERV[0] than just getting rid of toxic gasses (handles farts, too!). Worth every penny — one will remove stink from the entire 1000sqft house (including indoor cat litterbox), with partial heat/humidity recovery.
[0] Energy recovery vent, e.g. https://www.homedepot.com/p/Panasonic-WhisperComfort-60-20-5...
A while back, they thought that they might have found something at 700 MHz. Then went looking again and it was gone. My professor said that it was probably a CPU in the lab.
[1]: https://en.wikipedia.org/wiki/Axion_Dark_Matter_Experiment
Somebody could well have been walking across a field with a 1450 MHz generator. I don't know why; maybe it was a prototype of a portable microwave-oven/Walkman mashup. If so, it was leaky, and perhaps that's why it never caught on.
What's the reasoning for this? I've seen noted that the Wow signal of 1420 MHz is near the hydrogen line frequency, and is commonly detected astrophysically.
So is the reasoning just that, if you want to send a signal, then you might choose this frequency because other civilizations will probably have detectors tuned to it?
But then the flip-side of that is that if you detect this frequency, then it's almost certainly natural origin, from the excitation of hydrogen.
We only recorded the fact of the signal's existence, without enough resolution to make out any pattern within it. If the aliens were hoping we'd decode it, they were banking on us happening to catch their signal at a very specific instant in time, never to be repeated.
Actually it’s exactly what we did with the Arecibo message, our only attempt to make contact.
Also exactly what you'd expect if aliens were beaming a search signal into their sky, no?
My theory is that the government was planning to cut funding, and to stop that from happening someone deliberately created the interference. That's more likely than aliens going extinct after sending one single message.
Well, yeah, but I wasn't addressing that. My point is that any signal from an intelligent species is going to look exactly like the signal from someone walking past with an emitter.
I don't remember where I watched it, but the 2nd and 3rd links from a kagi search were for Prime and Apple TV.
They probably were mostly operating around 30 mhz in the CB band or 120-150 in the Ham or aircraft bands in that era, but harmonics are a thing
Statistically speaking, that's more likely than aliens going extinct after sending one single message.