EVE ! - Radio Amateurs bounce a signal off Venus

Pierre Will Investigate!

I've sent a shortwave radiogram to Newsline's April 1st Roving Reporter Pierre Pullinmyleg asking him to investigate this claim. Unfortunately, Pierre only reports for Newsline once a year and already has done so for 2009. So it will take a while to get his response. -- ITF

 

EVE deniers

Hey, all you guys that think EVE is impossible should do a little research about the history of radar astronomy. Signals have been bounced off Venus since the early 1960's from Goldstone observatory. Later, the big dish in Arecibo was used to do some crude mapping of the surface, long before any satellite was able to do so. This is how they figured out Venus has retrograde rotation.

This fine effort from DL-land is totally credible. The only thing radical or new is that “hams” did it in their spare time for fun and far less money. And it was a good test of some newer techniques in preparation for their ambitious mission to send a probe to Mars.

 

The antenna:

http://www.honeysucklecreek.net/other_stations/bochum/main.html

K2WH

 

You are correct. However, those radar studies were performed with much higher power and much bigger antennas. Watching the video and with a little understanding of the German language, it seems they were using 4kw at 2400 mhz. I do not know if that was input or output however.

If they have indeed heard echos off the surface of Venus then good for them. But, I'm having a hard time trying to understand the reason for the Mars probe. Is it supposed to be a signal source, a repeater etc.

K2WH

 

And, one has to take into account the surface absorption. I believe they say the moon reflects only about 5% of the RF signal it receives. No planet or moon is a perfect reflector.

 

Worked All Planets

CQ CQ CQ WAP CQ Worked all planets CQ!

Venus calling. Hello Tokyo it's raining here too!

Bouncing signals of Venus, surely that is about as likely as the Americans putting a man on the Moon in 1969?

I love the irony of the acronym EVE (the 1st woman) and astronomic symbol for Venus being the same a that of the femail of the species.

 

Such cynics!

This is very cool.

 

It's already April 1 in some parts of the world...

I am also doubtful. I haven't been reading my AMSAT Journal lately, but I don't remember anything about a Mars mission. The video link was to a legit website with a professionally produced video. I only wish I had kept up my German. The video also panned a poster of AMSAT launches, with the Mars mission slated for an Arianne V.

 

Simple math.... 100 million kM travel time is 333 seconds. That is 5 + 1/2 minutes, not "almost 5 minutes". A problem with translating ?

Is it feasible?

Path loss in USA units is 36.6 + 20*log(F in MHz) + 20*log(d in miles)

Converting to USA units (since most users on qrz.com are in the USA)

100 million km is approximately 62 million miles round trip.

path loss in dB is 36.6 + 20*log(2400) + 20*log(62million)
36.6 +67.6 + 155 = 259 dB

So 259 dB just for the distance it travels.
Someone stated that the moon reflects 5% of the incident signal. I would expect much less than that, but for perspective, 5% reflected would be "13 dB loss". If it reflected 1% that would be 20 dB. So the amount reflected is not a big factor in my assumptions compared to 259 dB.

Let's say 280 dB total.

If the transmitter power is 4 kW that's 66 dBm. If the antenna gain of that 20 m dish is 55 dB, the e.r.p. is 121 dBm (=91 dBW) = let's call it 90 dBW which is a simple 1 Billion watt erp.

So... 121 dBm erp - 280 dB path loss = -160 dBm erp at the receive antenna.

-160 dBm to a 20 m dish with 55 dB gain is -105 dBm.

Which is plenty of signal even for 'voice grade' narrow band FM.

If they were using very small bandwidths (just a couple of HZ) they could easily work with signal levels of -130 dBm.

So it may be possible. However before I believe this claim of E.V.E. propagation.... I would want to hear from some astronomers. There's too much about space that I don't know.

Can the 'simple' path loss formula be used in space? What about all that 'space dust' or other stuff out there. What kind of dispersion and absorption and reflection would it cause over that kind of distance?

What about Faraday rotation? Over that distance...what would happen to the electromagnetic signal?

Doppler shift. I would not know where to look up the relative velocities of Earth and Venus. I would not faint if someone calculated the doppler shift would be 500 MHz.

Any astronomers here care to take a guess at the amount of signal reflection from Venus relative to the moon by just comparing the size of them?

 

Let's talk about signals into space...

Scientists have been sending signals into space for decades. Many of those have been intentional. Most just junk we broadcast to ourselves.

I have read that if someone were on, say proxima centurie, or alpha centurie, or whatever that binary system that is a mere 4 light years away, they would be able to hear some of our milatary radar transmissions. That is all. They would not be able to hear Rick Dees and his FM stereo program, nor George Noorey and his Coast to Coast AM program, nor would they be able to watch Star Trek, or Desperate Housewives, or Gilligan's Island reruns.

Maybe a SETI transmission, but those are sparotic at best. Milatary radar is constant, powerful and identifiable as manmade.

Just my input . And by the way, I like the idea of an amateur space probe to mars. The astronauts have hams within their ranks, and a repeater way out younder standing ready for arrival of users would be neat. But, I really belive a luner lander with a ham repeater would not only be more fun and financially accessable to the average user, but more useful. It cannot be wacked out of orbit by space debris, and it's footprint is huge. I do not know why NASA or industry hasn't come up with a luner lander repeater as of yet. Useful.

 

That's not quite correct. With earth-level technology at that distance, they would be able to learn quite a bit of interesting information about us. Here's an excellent article on the subject:

http://history.nasa.gov/CP-2156/ch5.4.htm

Basically, the most interesting thing they would be able to monitor would be the video carriers (but not the modulation itself) of VHF and UHF TV transmitters. From these carriers, they would be able to make quite a few conclusions, including the size and period of the earth's orbit around the sun, the diameter of the earth, and the period of its rotation about its axis.

In addition, they would be able to determine the terrestrial locations of these transmitters, and from this information, they would be able to make a crude map of the populated areas of the earth, if they made the correct assumption that the transmitters were located in populated areas.

 

Believe-it-or-not

I also am mystified as to why we have no repeater on the moon. If they'd have sent a ham radio and op up there in '69, there would be no plausible reason for today's diehard skepticism. Thousands of QSO's (with the expected directivity and propagation delay) would have proven without a doubt, that we were really there.

A repeater on the moon? A wide footprint for sure. But can you imagine all the QRM? But then, maybe that would divert some of the more blatant jammers we now have on the HF bands.

Speaking of innovation, allow me to toot my own horn here. Did you know that, under the right conditions, you can get up to a 20db signal enhancement, using an HF turnstile antenna? (Taking advantage of the rotation of solar wind partcles in the ionosphere, as they encounter earth's magnetic field.)

No 'April fools' joke.

(More on my bio page).


73,

Jim, W9JEF

 

Gottya! April Fool! There is no such place as Venus!

Ah, a debunked story, now you have my attention ... not!

It's like Obamabad's visit to the UK for April 1st, a sick joke with impeccable bad timing, not to mention taste.

And just when you thought it was safe to go back to the Internet ...

Everybody knows it is impossible to bounce radio waves off a non existant place. Another Conspiracy neatly debunked for the masses!

 

What frequency was used to transmit this "signal"? What equipment was used, aside from the 2.4 amplifier mentioned in the post? What was the "signal" that was sent - was it just a burst of open carrier or was it a message?

Why is none of the above mentined? Why is the link to the article in German and not translated in English for the convenience of non-German speaking/reading people on this site?

Yeah, right ... and NASA actually landed people on the Moon.

AA1MN

 

I don't think anyone has said this yet, but these guys were by no means hearing their HI HI after it bounced off of venus. The quote above says that they used a fast fourier transform (FFT) analysis over a 5 minute period. This takes the time domain signals and turns them into frequency domain signals. Over the 5 period, the received data was added, and the frequency components displayed on a screen. What they saw after 2 minutes was a spike at or around 2.4GHz, meaning that the receiver was receiving more information at 2.4GHz than at other frequencies, which would be other earth based signals and noise of course. Work out the timing from when the transmission was sent from Earth, and when it should return after traveling to Venus and back, make sure this timing lines up with when the spike at 2.4GHz appears and if they are close then you can assume the signal is coming from Venus.

Once again, they didn't "hear" a signal bounced off of venus, it was detected over a period of several minutes by a spectrum analyzer. Not any way to make a QSO, but certainly impressive.

I don't know what the required signal levels for this analysis to work are, but they are much lower than that required to receive discernable code or voice.