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Title: 47 year old television signals bouncing back to Earth
Source:
BBC
URL Source: http://www.rimmell.com/bbc/news.htm
Published: Apr 1, 2009
Author: BBC
Post Date: 2011-12-17 00:27:12 by X-15
Keywords: Dr. Who, space
Views: 526
Comments: 40
While searching deep space for extra-terrestrial signals, scientists at the Arecibo Observatory in Puerto Rico have stumbled across signals broadcast from Earth nearly half a century ago. Radio astronomer Dr. Venn described how he made the historic discovery after analysing a number of signals originating from the same point in space. "I realised the signal was in the VHF Band and slap bang in the middle of 41-68 MHz. It was obviously old terrestrial television broadcasts, but they seemed to be originating from deep space." After boosting and digital enhancement the resulting video signals are remarkably clear. Responding to questions, Dr Venn was at pains to explain that little green men are not showing repeats of old Earth shows. "They are signals that left the Earth about 50 years ago and have bounced off an object or more likely a field of objects some 25 light years away". Radio signals travel at approximately 300,000 kilometers per second. The distance the vintage signals have traveled in the intervening years is vast and whatever they are bouncing off is too far away to see with even the most advanced optical telescopes. "...we asked NASA if they could point Hubble at the centre of what we've named the 'Bounce Anomaly'. NASA were very keen to help once they had seen our data." However the $3 billion space telescope was unable to produce any clues as to what the signals are bouncing off. One theory is a massive cloud of asteroids is acting like a mirror in space reflecting radio signals from our past, back to us. A BBC team have been working closely with Dr Venn's team to help recover the signals. BBC Television historian Peter Wells, explained "We now know these are original broadcasts. So far we have recovered about 7 weeks of old television signals from space. Every day in our lab is like traveling back in time. And speaking of which we have just started the digital recovery of signals that contain lost Doctor Who episodes. The BBC will be archiving all the recordings recovered from space and there are plans to broadcast some of the highlights later in the year.
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#1. To: X-15 (#0)
I find it highly unlikely that an earth generated radio signal would have enough power to bounce off an object, no matter HOW large, 25 light years away. I'd like to know what the power level was of the received signal. I bet it's higher than one would think. Now either it's a NWO plot to trick people into thinking their are aliens out there beaming back our old TV shows, or it really IS aliens bouncing our old TV signals back as a way to say "hello world". I'd side with the latter. Why? In space radio signals would not lose any power cause it is a virtual vacuum. There may be aliens out there, but I highly doubt they are broadcasting our TV signals back at us. God is always good!
In five more years we will get the original Apollo broadcasts bouncing back, that might be one to record. ;) God is always good!
This had me so excited. Then I noticed that it was published on April Fool's day 2009. Now I'm bummed out. Figured I'd come out of lurking and point that out before too many others fell for it too.
I'm surprised anyone would believe something that defuses so much could do this.
194 episodes of "i love lucy", still contaminating the universe. god save us all
I really wanted to see those Dr Who episodes, though.
That was what made the story intriguing at first. It would have had to have been intercepted, amplified, and beamed back by technology much better than ours. Any tv signal that just reflected back to us would be way too faint for us to detect.
Anyone remember the movie with Jody Foster, I think it was called "Contact"? Advanced aliens did this exact thing, broadcasting a TV signal back to earth, but including plans to build some interdimensional traveling pod.
appreciate that! hope you come out often now. ;)
They do lose power since the signal is not focused into a beam. It insteads expands just like normal light, so the signal is 1/4th the strength at twice the distance. Signals 27 lightyears away are about non existent.
I missed that movie, but yeah that would be a real attention getter.
Thanks Christine, I'll post more often.
They do lose power since the signal is not focused into a beam. It insteads expands just like normal light, so the signal is 1/4th the strength at twice the distance. Signals 27 lightyears away are about non existent. It follows the inverse square law - the signal decreases in strength with the square of the distance. At 27 light years it would be so faint as to be indetectable. So, for example if you have a signal strength of 1 at 2 feet it will be 1/4 at 4 feet, and 1/16th at 8 feet. At 27 light years it would be so infinitesimal as to be nonexistant. I don't think you are accounting for the vacuum of space. I know they lose power in our atmosphere, but I doubt they would lose as much power in space. Edit--- I did some research on this and found out that in a vacuum your formula for loss of signal strength does not apply. Here is the Free Space Path Loss formula, where Free Space is a vacuum. FSPL = 32.44 + 20log(d) + 20log(f) Where FSPL is the Free Space Path Loss (in dB), d is the distance from Thus the spreading loss is only 6dB every time you double the distance. God is always good!
April fools joke in December? Why?
God is always good!
See post 15.
God is always good!
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The relationship between morality and liberty is a directly proportional one. "If you love wealth more than liberty, the tranquility of servitude better than the animating contest of freedom, depart from us in peace. We ask not your counsel nor your arms. Crouch down and lick the hand that feeds you. May your chains rest lightly upon you and may posterity forget that you were our countrymen.” —Samuel Adams
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The relationship between morality and liberty is a directly proportional one. "If you love wealth more than liberty, the tranquility of servitude better than the animating contest of freedom, depart from us in peace. We ask not your counsel nor your arms. Crouch down and lick the hand that feeds you. May your chains rest lightly upon you and may posterity forget that you were our countrymen.” —Samuel Adams
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The relationship between morality and liberty is a directly proportional one. "If you love wealth more than liberty, the tranquility of servitude better than the animating contest of freedom, depart from us in peace. We ask not your counsel nor your arms. Crouch down and lick the hand that feeds you. May your chains rest lightly upon you and may posterity forget that you were our countrymen.” —Samuel Adams
He is sneaky, the timing of that post was perfect.
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The relationship between morality and liberty is a directly proportional one. "If you love wealth more than liberty, the tranquility of servitude better than the animating contest of freedom, depart from us in peace. We ask not your counsel nor your arms. Crouch down and lick the hand that feeds you. May your chains rest lightly upon you and may posterity forget that you were our countrymen.” —Samuel Adams
; ) :D Even called out "Guess what they discovered..." to the wife. Only to go "Uh... nevermind" a bit later. She laughed. When I saw that others were doing the same, I had to say something.
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The relationship between morality and liberty is a directly proportional one. "If you love wealth more than liberty, the tranquility of servitude better than the animating contest of freedom, depart from us in peace. We ask not your counsel nor your arms. Crouch down and lick the hand that feeds you. May your chains rest lightly upon you and may posterity forget that you were our countrymen.” —Samuel Adams
Didn't it come from Johnny Dangerously? It's been a while since I've seen it.
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The relationship between morality and liberty is a directly proportional one. "If you love wealth more than liberty, the tranquility of servitude better than the animating contest of freedom, depart from us in peace. We ask not your counsel nor your arms. Crouch down and lick the hand that feeds you. May your chains rest lightly upon you and may posterity forget that you were our countrymen.” —Samuel Adams
Merry Christmas!!!! I spared no expense for my fellow 4um members this holiday. hehehehe.....
"The real deal is this: the ‘royalty’ controlling the court, the ones with the power, the ones with the ability to make a difference, with the ability to change our course, the ones who will live in infamy if we pass the tipping points, are the captains of industry, CEOs in fossil fuel companies such as EXXON/Mobil, automobile manufacturers, utilities, all of the leaders who have placed short-term profit above the fate of the planet and the well-being of our children." - James Hansen
#2. To: FormerLurker (#1)
I find it highly unlikely that an earth generated radio signal would have enough power to bounce off an object, no matter HOW large, 25 light years away.
#3. To: X-15 (#0)
(Edited)
The BBC will be archiving all the recordings recovered from space and there are plans to broadcast some of the highlights later in the year.
#4. To: X-15 (#0)
#5. To: Trow (#4)
#6. To: Trow (#4)
#7. To: lead.and.lag (#6)
#8. To: Ferret (#5)
I'm surprised anyone would believe something that defuses so much could do this.
#9. To: Trow (#8)
#10. To: Trow (#4)
Figured I'd come out of lurking and point that out before too many others fell for it too.
#11. To: RickyJ (#2)
In space radio signals would not lose any power cause it is a virtual vacuum.
#12. To: Pinguinite (#9)
#13. To: christine (#10)
#14. To: Pinguinite, RickyJ (#11)
In space radio signals would not lose any power cause it is a virtual vacuum.
#15. To: Pinguinite (#11)
(Edited)
It insteads expands just like normal light, so the signal is 1/4th the strength at twice the distance.
transmitter antenna (in km), and f is the frequency of RF signal (in MHz).
#16. To: X-15 (#0)
#17. To: Original_Intent (#14)
#18. To: Ferret (#5)
#19. To: lead.and.lag (#6)
#20. To: Trow (#4)
#21. To: Eric Stratton, Trow (#20)
#22. To: Ferret (#21)
#23. To: Eric Stratton, Ferret, all (#20)
You sneaky bastage!
In a way, I'm kind of sorry I spoiled X-15's fun. But I fell for the story hook , line, and sinker for a couple minutes there.
#24. To: Trow (#23)
#25. To: Eric Stratton (#24)
One of the characters kept mispronouncing his cuss words, "farging icehole", "cork soaker" ect.
#26. To: Trow (#25)
#27. To: RickyJ (#16)
April fools joke in December? Why?
-Alex Kurtagic
#28. To: RickyJ (#2)
Power radiated from an antenna follows an inverse square law, where the reciprocal of distance squared is a fundamental factor in the actual formula for power radiated over a distance; From Inverse- square law The intensity (or illuminance or irradiance) of light or other linear waves radiating from a point source (energy per unit of area perpendicular to the source) is inversely proportional to the square of the distance from the source; so an object (of the same size) twice as far away, receives only one- quarter the energy (in the same time period). More generally, the irradiance, i.e., the intensity (or power per unit area in the direction of propagation), of a spherical wavefront varies inversely with the square of the distance from the source (assuming there are no losses caused by absorption or scattering). For example, the intensity of radiation from the Sun is 9126 watts per square meter at the distance of Mercury (0.387 AU); but only 1367 watts per square meter at the distance of Earth (1 AU)—an approximate threefold increase in distance results in an approximate ninefold decrease in intensity of radiation. In photography and theatrical lighting, the inverse-square law is used to determine the "fall off" or the difference in illumination on a subject as it moves closer to or further from the light source. For quick approximations, it is enough to remember that doubling the distance reduces illumination to one quarter;[4] or similarly, to halve the illumination increase the distance by a factor of 1.4 (the square root of 2), and to double illumination, reduce the distance to 0.7 (square root of 1/2). When the illuminant is not a point source, the inverse square rule is often still a useful approximation; when the size of the light source is less than one-fifth of the distance to the subject, the calculation error is less than 1%.[5] The fractional reduction in electromagnetic fluence (¦) for indirectly ionizing radiation with increasing distance from a point source can be calculated using the inverse-square law. Since emissions from a point source have radial directions, they intercept at a perpendicular incidence. The area of such a shell is 4Àr2 where r is the radial distance from the center. The law is particularly important in diagnostic radiography and radiotherapy treatment planning, though this proportionality does not hold in practical situations unless source dimensions are much smaller than the distance. Let the total power radiated from a point source, for example, an omnidirectional isotropic antenna, be P. At large distances from the source (compared to the size of the source), this power is distributed over larger and larger spherical surfaces as the distance from the source increases. Since the surface area of a sphere of radius r is A = 4Àr 2, then intensity I (power per unit area) of radiation at distance r is The energy or intensity decreases (divided by 4) as the distance r is doubled; measured in dB it would decrease by 6.02 dB per doubling of distance. In space radio signals would not lose any power cause it is a virtual vacuum. There may be aliens out there, but I highly doubt they are broadcasting our TV signals back at us.
Light and other electromagnetic radiation
Example
"The real deal is this: the ‘royalty’ controlling the court, the ones with the power, the ones with the ability to make a difference, with the ability to change our course, the ones who will live in infamy if we pass the tipping points, are the captains of industry, CEOs in fossil fuel companies such as EXXON/Mobil, automobile manufacturers, utilities, all of the leaders who have placed short-term profit above the fate of the planet and the well-being of our children." - James Hansen
#29. To: RickyJ (#2)
So, if you have a megawatt TV transmitter, the power 25 light years away would be as follows; Let's first find the actual distance in kilometers. Speed of light = 300,000 kilometers per second So 25 light years is equal to 25 y * 300,000 km/s * 31,536,000 s/y = 236,520,000,000,000 kilometers, or roughly 237 x 1012 kilometers for short. So then, with the formula 1,000,000 Watts/(4Pi * (237 x 1012)2) = 5.64 x 10- 26 Watts Now that's the power 25 light years away. Now being that any sort of object will have less than perfect reflectivity, we should deduct some of the power due to the loss involved in the actual reflection. But at that power level, NO receiver would be able to pick up what's 25 light years away anyways, never mind how low it'd be on the return trip back to earth. But for fun, lets assume 100% reflectivity, which would never happen in nature, but let's just assume there is an ideal reflector there. The power when it gets back to earth would be as follows; 5,64 x 10-26 W / (4Pi * (237 x 1012)2) = 3.18 x 10-57 Watts. That's 57 positions to the right of the decimal point, or 56 zeroes in front of 318 Nothing on earth would detect that.
Number of seconds in a year = 60 s/m * 60 m/h * 24 h/d * 365 d/y = 31,536,000 sec/year , we get
"The real deal is this: the ‘royalty’ controlling the court, the ones with the power, the ones with the ability to make a difference, with the ability to change our course, the ones who will live in infamy if we pass the tipping points, are the captains of industry, CEOs in fossil fuel companies such as EXXON/Mobil, automobile manufacturers, utilities, all of the leaders who have placed short-term profit above the fate of the planet and the well-being of our children." - James Hansen
#30. To: RickyJ, Original_Intent (#15)
And that is derived from the inverse square law which I just posted. How many times do you think the distance is doubled in terms of kilometers in dealing with 25 light years? There are QUITE a few doublings there. Thus the spreading loss is only 6dB every time you double the distance.
"The real deal is this: the ‘royalty’ controlling the court, the ones with the power, the ones with the ability to make a difference, with the ability to change our course, the ones who will live in infamy if we pass the tipping points, are the captains of industry, CEOs in fossil fuel companies such as EXXON/Mobil, automobile manufacturers, utilities, all of the leaders who have placed short-term profit above the fate of the planet and the well-being of our children." - James Hansen
#31. To: RickyJ (#15)
And yeah, it was an April Fools joke I suppose...
"The real deal is this: the ‘royalty’ controlling the court, the ones with the power, the ones with the ability to make a difference, with the ability to change our course, the ones who will live in infamy if we pass the tipping points, are the captains of industry, CEOs in fossil fuel companies such as EXXON/Mobil, automobile manufacturers, utilities, all of the leaders who have placed short-term profit above the fate of the planet and the well-being of our children." - James Hansen
#32. To: RickyJ, Original_Intent (#15)
And oh yeah, a 3db loss is a 50% power loss, so 6db is a 75% loss. In other words, for every 6db loss the power is reduced to 1/4 of its prior level. Thus the spreading loss is only 6dB every time you double the distance.
"The real deal is this: the ‘royalty’ controlling the court, the ones with the power, the ones with the ability to make a difference, with the ability to change our course, the ones who will live in infamy if we pass the tipping points, are the captains of industry, CEOs in fossil fuel companies such as EXXON/Mobil, automobile manufacturers, utilities, all of the leaders who have placed short-term profit above the fate of the planet and the well-being of our children." - James Hansen
#33. To: All (#29)
Hmmm. I think I forgot to use meters instead of kilometers. Since a kilometer is 1000 meters, and since the distance factor is in the denominator of the equation and needs to be squared, my results are 1 million times too high. So the power would be one millionth of what I calculated, as such the final resulting power arriving back to earth would be 3.18 x 10-63 watts...
"The real deal is this: the ‘royalty’ controlling the court, the ones with the power, the ones with the ability to make a difference, with the ability to change our course, the ones who will live in infamy if we pass the tipping points, are the captains of industry, CEOs in fossil fuel companies such as EXXON/Mobil, automobile manufacturers, utilities, all of the leaders who have placed short-term profit above the fate of the planet and the well-being of our children." - James Hansen
#34. To: FormerLurker (#32)
Thanks for the info. Looks like the spread loss makes radio contact over vast distances like light years almost impossible to achieve, that truly sucks.
God is always good!
#35. To: RickyJ (#34)
You're welcome Ricky. I never say impossible though, as there might be other technologies that might allow such communications, such as quantum events or some other exotic technology or fundamental law yet to be discovered which might allow such communications in the future.
"The real deal is this: the ‘royalty’ controlling the court, the ones with the power, the ones with the ability to make a difference, with the ability to change our course, the ones who will live in infamy if we pass the tipping points, are the captains of industry, CEOs in fossil fuel companies such as EXXON/Mobil, automobile manufacturers, utilities, all of the leaders who have placed short-term profit above the fate of the planet and the well-being of our children." - James Hansen
#36. To: FormerLurker (#33)
Keep going we'll get to a google of zeros yet. Hee, hee. Hmmm. I think I forgot to use meters instead of kilometers. Since a kilometer is 1000 meters, and since the distance factor is in the denominator of the equation and needs to be squared, my results are 1 million times too high. So the power would be one millionth of what I calculated, as such the final resulting power arriving back to earth would be 3.18 x 10-63 watts...
#37. To: RickyJ, Pinguinite, Original_Intent, All (#15) (Edited)
What's the scientific explanation for our sun and all the stars burning as they do and for so long if space is a vacuum? Seems to me the logical presumption would be that there's oxygen in the space around them. Edit to reword last sentence. accounting for the vacuum of space.
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"They're on our left, they're on our right, they're in front of us, they're behind us...they can't get away this time." -- Col. Puller, USMC
#38. To: Pinguinite, RickyJ (#11)
in extremely simple terms, the signals make like a vapor and dissipate.
the most factual thing ever posted by buckeroo
I have no freaking' clue. buckeroo posted on 2010-07-24 21:33:00 ET
#39. To: GreyLmist (#37) (Edited)
Seems to me the logical presumption would be that there's oxygen in the space around them. The sun is not burning, so it needs no oxygen. The heat and light produced from it is from nuclear fusion. What's the scientific explanation for our sun and all the stars burning as they do and for so long if space is a vacuum?
God is always good!
#40. To: RickyJ (#39)
The heat and light produced from it is from nuclear fusion. I thought I already answered this but things that make ya go hmmm. So how do you explain why all those stars we see look practically the same size, no matter how far away they are? The farther away, the bigger they have to be so as to appear comparably similar in mass to the ones that are closer to earth? The sun is not burning, so it needs no oxygen.
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"They're on our left, they're on our right, they're in front of us, they're behind us...they can't get away this time." -- Col. Puller, USMC
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