> And until now, no one has taken a detailed survey of the part of the sky where the signal originated. In this new effort, the researchers chose to rectify that situation by conducting a dual-telescopic study of the part of the night sky that is believed to be the source of the signal.
> We should have seen it again when we looked for it 50 times.
This is a weird thing to say. If the Wow! Signal were indeed from intelligent life, what’s to say it’s not like our own Arecibo Message, which was a one-time transient burst transmission?
When you use a telescope like this, you aren't looking for intentional communications. What you are looking for is emissions unrelated to intergalactic communications. The hypothesis is almost every civilization should have a huge emission pattern all over the practically usable RF spectrum.
Just on earth for example, television transmitters are constantly broadcasting a very high power signal on all kinds of different frequencies.
>Just on earth for example, television transmitters are constantly broadcasting a very high power signal on all kinds of different frequencies.
These are isotropic radio emissions, and would not be discernible from background radiation at more than a lightyear or so away from Earth, since its intensity diminishes as the inverse square of distance.
>What you are looking for is emissions unrelated to intergalactic communications. The hypothesis is almost every civilization should have a huge emission pattern all over the practically usable RF spectrum.
This communication would likely be via directed radio emissions (e.g. the Wow! Signal or Arecibo Message), which we could only pick up if our detector were perfectly aligned with the source at the exact time the transmission arrives. Because of that inverse square law, it would be an enormous waste of power to communicate via isotropic radio emissions.
You're assuming that cosmic background radiation is uniformly distributed. It is not.
TV transmissions are most definitely not isotropic for any commercial installation. They use directional antennas to avoid sending power directly down into the earth for example.
I'm not even aware of a single commercial radio installation with anything approximating an isotropic pattern.
While they may not be perfectly isotropic, they are far from being directional (most TV transmitters are monopoles with uniform azimuthal radiation) and would still not be distinguishable from background radiation (regardless of its distribution) at more than a light year or two away [0]. Highly directional radio emissions an order of magnitude more powerful than the strongest transmitters on Earth would only be visible at approximately 100 light years away [1].
Presumably the ability to observe at different wavelengths. Most telescopes have (in not the incredible flagship like HST and JWST) observe in one wavelength, say infrared or visual.
Wasn't this always likely assumed to be some catastrophic space event that just lined up right for us?
On the life speculation part that people enjoy: If you were going to try communicate with the galaxy it seems strange not use an already powerful source in your neighbourhood like a star, then encode your message in blocking that out, perhaps with huge expanding/contracting panels on a satellite.
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[ 6.5 ms ] story [ 37.6 ms ] threadwhy wait 40 years?
> We should have seen it again when we looked for it 50 times.
This is a weird thing to say. If the Wow! Signal were indeed from intelligent life, what’s to say it’s not like our own Arecibo Message, which was a one-time transient burst transmission?
Just on earth for example, television transmitters are constantly broadcasting a very high power signal on all kinds of different frequencies.
These are isotropic radio emissions, and would not be discernible from background radiation at more than a lightyear or so away from Earth, since its intensity diminishes as the inverse square of distance.
>What you are looking for is emissions unrelated to intergalactic communications. The hypothesis is almost every civilization should have a huge emission pattern all over the practically usable RF spectrum.
This communication would likely be via directed radio emissions (e.g. the Wow! Signal or Arecibo Message), which we could only pick up if our detector were perfectly aligned with the source at the exact time the transmission arrives. Because of that inverse square law, it would be an enormous waste of power to communicate via isotropic radio emissions.
TV transmissions are most definitely not isotropic for any commercial installation. They use directional antennas to avoid sending power directly down into the earth for example.
I'm not even aware of a single commercial radio installation with anything approximating an isotropic pattern.
[0] https://physics.stackexchange.com/a/245562
[1] https://arxiv.org/pdf/astro-ph/0610377.pdf
On the life speculation part that people enjoy: If you were going to try communicate with the galaxy it seems strange not use an already powerful source in your neighbourhood like a star, then encode your message in blocking that out, perhaps with huge expanding/contracting panels on a satellite.