It was meant as a joke (do I really have to point that out?) and we were specifically talking about ducks. 
Not a Drill: SETI Is Investigating a Possible Extraterrestrial Signal From Deep Space
- Thread starter timtonruben359
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It was meant as a joke (do I really have to point that out?) and we were specifically talking about ducks.
So did I. (mean that as a joke, that is).
Besides, for all we know Donald has been neutered, and that would explain why he only has nephews and not children.
Based on the received signal's characteristics, aliens would have to generate about 100 billion billion watts of energy to blast it out in all directions. And they'd still have to produce more than 1 trillion watts if they beamed it only to Earth for some reason, Shostak said.
http://www.space.com/33893-seti-investigates-strong-candidate-signal.html
What source could created this powerful signal? If not aliens then what about VY Canis Majoris? VY Canis Majoris is a Red Hypergiant compared to our sun.
https://en.wikipedia.org/wiki/VY_Canis_Majoris
http://www.space.com/33893-seti-investigates-strong-candidate-signal.html
What source could created this powerful signal? If not aliens then what about VY Canis Majoris? VY Canis Majoris is a Red Hypergiant compared to our sun.
https://en.wikipedia.org/wiki/VY_Canis_Majoris
1 trillion Watts = 10^12 W
100 billion billion Watts = 10^20 W
The energy output of a star = 7.16x10-7 r^2 T^4 W where r is the radius of the star in metres and T is its surface temperature in Kelvin. For the Sun and HD 164595 (which has a slightly lower mass and temperature than the Sun), the energy output is about 4x10^26 W -- greater by 100 trillion times than 1 trillion Watts and 1 million than 100 billion billion Watts. So only a small proportion of the star's energy would have to be captured and used to generate the signal in either scenario.
http://www.schoolphysics.co.uk/age16-19/Astrophysics/text/Power_output_of_a_star/index.html
100 billion billion Watts = 10^20 W
The energy output of a star = 7.16x10-7 r^2 T^4 W where r is the radius of the star in metres and T is its surface temperature in Kelvin. For the Sun and HD 164595 (which has a slightly lower mass and temperature than the Sun), the energy output is about 4x10^26 W -- greater by 100 trillion times than 1 trillion Watts and 1 million than 100 billion billion Watts. So only a small proportion of the star's energy would have to be captured and used to generate the signal in either scenario.
http://www.schoolphysics.co.uk/age16-19/Astrophysics/text/Power_output_of_a_star/index.html
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Still would be quite a trick to pull it off. If it is an actual signal, props to them on making it happen.
Still would be quite a trick to pull it off. If it is an actual signal, props to them on making it happen.
Maybe it's not just a signal, it's a test firing of their new mega-ray!
Yeah, maybe it's Standard Galactic for, "This one's ripe!" The dinner bell.Maybe they're craving some BBQ humans?!?
That's no moon, it's a space station...
A
Amaris
Guest
That's how they killed Hitler.
They recorded it at about 11 Ghz, which puts it firmly in the microwave spectrum. That would be a good band for a long-range, point-to-point communications attempt, which is probably the main reason they asked SETI to investigate. OTOH, it would be very difficult to generate a signal of that intensity using known materials; that kind of output would probably vaporize the transmitter in the process (or that could be the whole point if the transmitter is something like a bomb-pumped maser).
But solar flares or CMEs producing microwaves at that frequency... is there actual precedent for that?
Sounds like ET is not phoning from home.
The peak power in the largest solar flares is about 10^20 W lasting from between a few minutes up to about an hour typically (at peak output, that's the equivalent of the total explosive yield of 25,000 1-megaton H bombs per second). I'd have to investigate how much of that is in the GHz region (presumably generated by magnetobremsstrahlung) but it's not inconceivable that there might be sufficient power available. However, the time series profile of a flare (in the microwave region, a rapid rise followed by a prolonged decay perhaps with additional superimposed rapid rises) doesn't look like what was reported (although that might be an artefact of how the signal was detected -- perhaps it swept through the lobe of the antenna sensitivity -- I'm not familiar with the observatory).
So we're getting all worked up for some stupid solar flares?
Perhaps there is a civilization there that isn't so advanced that they've "harnessed 100% of the output of the host star" or whatever - but IS advanced enough to use a naturally occurring flare of their star* to send a powerful signal toward a planet they think is a likely candidate for life like theirs?
*They'd be stellar flares. SOL-ar things come from SOL. *Our* sun. Yes, I'm being super pedantic.
I suspect there isn't enough power available in the microwave region to explain the signal (most of the power emitted is probably in high-energy X ray photons) but it might also depend on whether the EM radiation can be constrained to be emitted in a preferred direction because of the magnetic field configuration along which the electrons are gyrating.
if there're any people in the vicinity they must be getting one hell of a tan!
The flux density of solar radiation at 10 GHz received at the Earth = 1.24 x 10^-20 Wm^-2Hz^-1 = 1.24 x 10^6 Jy (Janskys)
http://www.cv.nrao.edu/course/astr534/Brightness.html
The peak flux density at 17 GHz from the great flare of July 7, 1966 measured at Earth = 10^-18 Wm^-2Hz^-1 = 10^8 Jy
http://adsabs.harvard.edu/full/1969SoPh....8..119H
Not quite the same frequency but it seems tenable that a flare can outshine a star by a factor of about 100 at a microwave frequency of between 10 and 20 GHz.
That's just a distance of 1 AU though. There are 63241 AU in a light year so at one light year distant, the flux density from the flare would drop to 1/(63241^2) of the value or 2.5 x 10^-10 * 10^8 Jy = 2.5 x 10^-2 Jy.
At the distance of HD164595 (95 ly), the flux density would drop by a further 1/(95^2) or 1.1 x 10^-4 to 2.75 x 10^-6 Jy.
http://www.centauri-dreams.org/wp-content/images/ratan_3.jpeg
ETA: The signal flux was 750 mJy or 0.75 Jy, which is much larger than my estimate. So I guess it's not a flare?
For comparison, the Wow! signal was a comparatively huge 60 Jy in a single 10 KHz wide channel at about 1.42 GHz.
http://www.astrobio.net/news-exclusive/mysteries-of-wow/
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Do you have a point to make?
Who is this addressed to? It seems you are having an one-sided conversation.
