First Contact? - Something odd, at any rate

Trebuchet · 2004-09-02 02:45:54

Seti@home has picked up a weird signal at a very suspicious wavelength, now recieved on three seperate occasions. They are cautioning that it might be some sort of new phenomena or some previously unknown glitch in the system.

On the other hand, it could be someone going "HELLO... HELLO..."

http://www.newscientist.com/news/news.j … 96341]Link

REB · 2004-09-02 07:04:16

Carl Sagan, in his book Pale Blue Dot, talks about some (just a few) unexplained signals that have been picked up by SETI. They never could confirm those signals because they could never pick them up again. Yet they were unexplainable.

I wish he was alive to see this news.

Cobra Commander · 2004-09-02 07:10:43

Yes, hell of a thing. Have to see what comes of this. Probably nothing, but ...

Palomar · 2004-09-02 07:18:29

Carl Sagan, in his book Pale Blue Dot, talks about some (just a few) unexplained signals that have been picked up by SETI. They never could confirm those signals because they could never pick them up again. Yet they were unexplainable.
I wish he was alive to see this news.

*Thanks for the little tingle down the spine.

Yeah, I have a copy of _Pale Blue Dot_ and recall that. The link in Trebuchet's post isn't working for me; will check SETI homepage.

--Cindy

Cobra Commander · 2004-09-02 07:21:20

Yes, I had some trouble with that link as well. On the second attempt it loaded. Slowly. Looks like it's getting some heavy traffic.

GraemeSkinner · 2004-09-02 07:46:39

http://news.bbc.co.uk/1/hi/sci/tech/3621608.stm]BBC News says that the signal according to Seti@home is not first contact - yet the news on the radio was a different story, perhaps it will be a while before someone says what is really going on :;):

Graeme

SpaceNut · 2004-09-02 07:58:56

The Guardian posts that it is in the direction of: "The signal appears to be coming from between the constellations Pisces and Aries, where there is no obvious star or planetary system within 1,000 light years. "

Say what ? No apparent source in the direction of reception and rotating 40 times faster than Earth.

Jokingly I hope The New York Times: Sorry, E.T., but Parcel Post May Beat Phoning Home.

Gives other history into simular projects of the past and there enormous calculations of chance in recieving of such signals. Mostly the dial tone has been heard in the past.

C M Edwards · 2004-09-02 14:08:16

Whoa. Behold the power of distributed computing!

Personally, I don't see how the signal characteristics preclude an intelligent origin. (How many human radio sources do you know of that adjust for the rotation of their planet? Thirty out of thirty million?)

Also, the idea of the signal being local is a little hard to swallow. Aricebo is a fixed azimuth telescope, but its receiver slides back and forth north and south all day long. Why isn't this "local signal" being detected whenever the geometry of the telescope is the same, regardless of where in the sky the telescope is pointing? Why would it show up when the telescope is in a different geometry relative to the ground (stellar targets move relative to the ground over the course of a year), but only when pointing at the same absolute stellar position regardless of the angle from the ground?

No, it's a real astronomical source. And its probably something new, because SETI@Home has algorithms to account for >90% of everything else.

An alien civilization's beacon in a 40 minute orbit would be new...

Shaun Barrett · 2004-09-02 16:52:09

Suppose it's a large interstellar spacecraft, carrying aliens, rotating once every 35 minutes or so to create artificial gravity for the journey.
???

[At least this hypothesis explains the lack of a star in the direction of the signal ... ]

Trebuchet · 2004-09-02 17:16:13

That might be... a large interstellar craft is going to have some kind of interaction with the hydrogen gas in its area. I would imagine that they could rule this out with more data.

Why aren't they taking a nice long look at this thing?

Trebuchet · 2004-09-02 17:17:53

Addendum: With a *different* radio telescope, just to be extra sure.

C M Edwards · 2004-09-03 09:07:42

Confirmation by a different radio telescope is vital, yes. It can rule out one of our own satellites, as well as local RFI. Also, Aricebo can only examine stellar objects for brief periods because it only points straight up.

Given the information that the signal frequency does go outside of the 250 Hz per signal bandwidth used by SETI@Home's algorithms, we can get a minimum guess as to its maximum speed if its in an orbit.

delta-f = f * delta-v / c

Thus,

delta-v = c * delta-f / f

where delta-f = 125 Hz = Doppler shift, f = 1420 MHz = Approximate Frequency, and c = 300 * 10^6 m/s = speed of radio waves. Delta-v is actually the velocity away from us, which in a circular orbit accelerates (drifts) most when the source is moving at a 45 degree angle to us.

So, the max delta-v is greater than 36 m/s. Each source is examined for only 12 seconds at a time, so it's safe to assume the actual drift is less than 500 Hz over each observation. That corresponds to a velocity of less than
150 m/s if this source is some sort of emitter in an orbit.

That sort of velocity does not correspond to a 35 minute circular orbit around a planet. Perhaps an asteroid or moon, but not a planet. It could be on the surface of a planet, but then there would be long periods with no apparent frequency drift at all. Unfortunately, there isn't enough data to tell the two cases apart.

The behavior of this source over time is vital to identifying it. Aricebo is not equipped to study it for more than a few minutes at a time. (The estimated period is probably just a projection.) We need to look at it with another scope.

Shaun Barrett · 2004-09-03 20:44:54

Interesting analysis of the numbers, CM.
You're right, of course, that the 35 minute period doesn't correspond to a planetary orbit. Low Earth Orbit takes about 1.5 hours and, while you could theoretically orbit much faster at a much lower altitude, the atmosphere would get in the way.
If you choose a body too small to retain an atmosphere, so that you can orbit relatively lower and faster, you're dealing with a weaker gravitational field. This works against you by lowering the achievable orbital velocity - too fast and you simply 'go off at a tangent', so to speak! The lunar orbital period of the Apollo craft was typically 2 hours+, for example.

This signal is a real mystery.
I hope it doesn't just fade away from public attention, as so many fascinating things seem to do. I hate it when the scientific community goes into 'radio silence' mode and leaves us in the dark.

~Eternal~ · 2004-09-04 10:25:17

A 1,000 light-years a way?
That seems unlikely that then that it is alien because humanity most certainly would not be interesting a thousand years ago.
No, if we are going to be contact in this era, it will most likely be within a 30ly range.

RobertDyck · 2004-09-04 16:29:12

Response from the http://www.seti.org/about_us/info_for_m … l.php]SETI Institute web site.

Sadly, the New Scientist, while it implies that a detection of an extraterrestrial signal is imminent, has inadvertently wandered into a sticky vat of hyperbole.
-- Seth Shostak

Shaun Barrett · 2004-09-04 17:28:46

Thanks, Robert.
The story sure sounds different when Seth Shostak tells it!

[I think I preferred the other version. ]

C M Edwards · 2004-09-08 14:17:17

Shostak is correct not to run around like Chicken Little, crying "The aliens are coming!" However, I don't think that he gives sufficient reason to discontinue the investigation. While it's still statistically possible that this signal could be just another hiccup, the signal has already met Clarke's rule of thumb statistical test: "Once is an accident, twice is a coincidence, three times is a conspiracy." As for the satellite RFI theory, that could very well be (more likely than aliens, in fact). But the projected period is not consistent with a geosynchronous satellite's daily drift.

Does that mean it's aliens? Heavens no. Not every spinning gas cloud is a sign of ET. I don't know what it is any more than Dr. Bell, Shostak, or anyone else. I only know it's currently unexplained, and probably actually exists.

At this point, I'll trust the results of observation with another telescope more than Shostak's speculation.

Shaun Barrett · 2004-09-08 18:52:53

Nevertheless, the source of the signal is most likely something mundane. (Notice I said "most likely", not certainly.)
So, maybe in a few weeks, a scientist somewhere will find this mundane origin for the signal, tell his/her friends and colleagues, and then promptly forget about it and get on with his/her life. Unfortunately, as usually seems to be the case, these people will neglect to pass on this information to the rest of us poor plebeians, who will be left wondering "what the hell happened to that mysterious signal from outer space?"!!
:hm:

C M Edwards · 2004-09-09 12:59:16

Unfortunately, as usually seems to be the case, these people will neglect to pass on this information to the rest of us poor plebeians, who will be left wondering "what the hell happened to that mysterious signal from outer space?"!!
:hm:

Hmm... published refutations of hoaxes and scientific errors are notoriously hard to find because they're not part of the popular literature. Often they're not even part of a published article, just a correction line on page ten. But they do exist.

We can probably keep an eye on this development if we want. Our research will have to be quite good, though.

Cobra Commander · 2004-09-09 13:13:12

Somehow waiting for a line-item correction in some obscure journal isn't quite how I imagined first contact. :laugh:

But then if we don't hear anything, it's probably nothing.

C M Edwards · 2004-09-09 13:55:01

Somehow waiting for a line-item correction in some obscure journal isn't quite how I imagined first contact. :laugh:

A first contact scenario in which the next great pioneer of humanity is... a librarian.

New Mars Forums

Announcement

#1 2004-09-02 02:45:54

Re: First Contact? - Something odd, at any rate

#2 2004-09-02 07:04:16

Re: First Contact? - Something odd, at any rate

#3 2004-09-02 07:10:43

Re: First Contact? - Something odd, at any rate

#4 2004-09-02 07:18:29

Re: First Contact? - Something odd, at any rate

#5 2004-09-02 07:21:20

Re: First Contact? - Something odd, at any rate

#6 2004-09-02 07:46:39

Re: First Contact? - Something odd, at any rate

#7 2004-09-02 07:58:56

Re: First Contact? - Something odd, at any rate

#8 2004-09-02 14:08:16

Re: First Contact? - Something odd, at any rate

#9 2004-09-02 16:52:09

Re: First Contact? - Something odd, at any rate

#10 2004-09-02 17:16:13

Re: First Contact? - Something odd, at any rate

#11 2004-09-02 17:17:53

Re: First Contact? - Something odd, at any rate

#12 2004-09-03 09:07:42

Re: First Contact? - Something odd, at any rate

#13 2004-09-03 20:44:54

Re: First Contact? - Something odd, at any rate

#14 2004-09-04 10:25:17

Re: First Contact? - Something odd, at any rate

#15 2004-09-04 16:29:12

Re: First Contact? - Something odd, at any rate

#16 2004-09-04 17:28:46

Re: First Contact? - Something odd, at any rate

#17 2004-09-08 14:17:17

Re: First Contact? - Something odd, at any rate

#18 2004-09-08 18:52:53

Re: First Contact? - Something odd, at any rate

#19 2004-09-09 12:59:16

Re: First Contact? - Something odd, at any rate

#20 2004-09-09 13:13:12

Re: First Contact? - Something odd, at any rate

#21 2004-09-09 13:55:01

Re: First Contact? - Something odd, at any rate

Board footer