A post from Cracked’s newsfeed, now circulating the internets, has it that “1 percent of static on an analog tv [the video snow is pictured] tuned to a dead channel is due to radiation left over from the Big Bang.”
Huh?
I thought is was more like 10 or 30 percent. I remember reading that you can see the microwave backgraound and thinking “that’s cool!”, but then reading further basically what the OP wrote: Tune to a blank channel, and roughly 10 percent of the static dots are from the Big Bang.
Well which ones?
(I’m still bitter.)
I found this old SDMB thread which includes a cite (post #4, now a dead link) that 25% of the static comes from cosmic rays (apparently, further discussion says it is incorrect about it being CMBR), but this isn’t the same (another poster (#6) says 1% is from CMBR).
It’s going to depend a lot on the particular TV involved. The TV circuitry itself will generate noise. You can google “thermal noise” for more details on that. There will also be noise generated from stuff here on the earth, so if you are in a big city you’ll get more of that type of thing where if you are out in the country you won’t get so much. And then yes, some small amount will come from cosmic background noise.
I wouldn’t expect cosmic background noise to be more than 10 or 20 percent under the best of conditions, and it’s certainly going to be a lot less than that in areas where other types of noise are more prevalent. Generally speaking, lower quality and older televisions will generate more thermal noise.
But even so, cosmic radiation is a lot more than the microwave radiation from the big bang.
I have definitely heard this from other sources (not that we need any more prestigious than ‘Cracked’, if such a thing even exists). Most recently, I think, from ‘A Universe From Nothing’ by Lawrence M. Krauss.
The 1% figure has been floating around the net for years.
Some quick Googling, with uncertain results (for me):
An old SciAm article–no author here, secondary cite from astro magazine–
There is discussion of it at a higher level than I can follow at
Can TV Antennas Pick Up CMB Radiation?. Maybe this has some good grist for your mills.
Any interpreters for me?
Wiki has a large demi-portal to the topic of “noise,” BTW
Well, I did get out of the hunt for the Straight Dope so far is that static snow is called “ant war” or fleas or bugs in other countries.
Do the Eskimos have a hundred words for “ant war?”