Starship Asterisk*

Chris Peterson wrote:

Ann wrote:Like Owlice said, we can never prove a negative - that is, if we don't find anything at all, that doesn't prove much at all - so we can go on searching and searching and searching pretty much indefinitely without finding anything, and still say that we should go on searching.

An important, and often overlooked aspect of science, is that proof is not a requirement. The longer we search, and the more approaches we use (different frequencies, different sensitivities, different search protocols), the more information we have. That is, we don't just have a single piece of information, "no life detected", but we can have a lot of data which places constraints on what might be out there. For instance, we might say with near certainty that we know that there is no intelligent life on Star X which is using unfocused radio with a given power level and a given spectrum.

Ann wrote:
Suppose there are intelligent beings on a planet orbiting a star ten light-years away. Let us suppose that like us, they are not deliberately sending signals into space to draw attention to themselves, but like us, they are using a kind of SETI system to listen for signals from others. Coincidentally enough, their SETI system is incredibly similar to ours, with pretty much exactly the same capability of detecting signals.

Would they hear us?

If not, would they "almost hear us", or wouldn't they even come close to hearing us?

In other words, if there was a civilisation similar to ours ten light-years away, a civilisation that is not deliberately sending signals into space to call attention to themselves, what chances would we have to hear them?

NoelC wrote:Heh, the increased interest this image has caused must have shut down the servers - many of the links in the caption just don't work.

-Noel

owlice wrote:
The links were checked two days before this APOD went live; they worked then.

We've killed the servers!

http://mst3k.wikia.com/wiki/Hangar_18 wrote:
<<Shortly after the launch of a satellite from a space shuttle, the satellite collides with an UFO in front of the crew's eyes. Because of an upcoming election, some politicians try to hide the crashed UFO inside Hangar 18.

* Hangar 18 is a 1980 film that was released to capitalize on the UFO interest of the era. Although it flopped rather badly (reportedly earning a gross of only $6 million), it tantalized those who saw government cover-ups of UFOs (such as the Roswell incident) as dirty laundry needing to be aired.

Prologue: In one of the shortest host segments ever, Joel introduces the film, and then it's movie sign!

Segment One: A meteor shower is about to strike the Satellite of Love! Joel explains the tragic consequences if the hull is punctured and the ship loses its oxygen: "No more Kibbles n' Bots, and no mid-morning pleasure stimulations!" Crow tells him to lighten up.

Segment Two: Joel purges Crow's memory, dumping all non-essential remembrances.
"Every Punky Brewster episode? Dump! The Lyle Wagner Penile Implant Show? Dump!"

Segment Three: Joel taps into Crow's brain, and shows him his first memory--the moment when he was first turned on. In the bit, Joel explains that "CROW" is actually an acronym, which stands for "Cybernetic Remotely-Operated Woman." Crow, alarmed to discover that he's really female, begins to panic ("Thirtysomething is on! I need some chocolate!") until Joel reveals it's all a joke.

Segment Four: Joel announces that there are nearly 1,000 members in the fan club now,
and the 1,000th member will win "self satisfaction and a Demon Dog!">>

lysandergray wrote:
I'm curious, why is this post/announcement identical to ones posted on 2004 March 7 and 2002 July 28?
They are perfect copies. Go to the APOD archive list and CTRL+F for "An Anomalous SETI Signal", you'll see what I mean.

owlice wrote:The links were checked two days before this APOD went live; they worked then.

We've killed the servers!

lysandergray wrote:I'm curious, why is this post/announcement identical to ones posted on 2004 March 7 and 2002 July 28? They are perfect copies. Go to the APOD archive list and CTRL+F for "An Anomalous SETI Signal", you'll see what I mean.

DavidLeodis wrote: Pehaps ET has realised he/she/it has been detected and has acted to limit the news before we are attacked!

owlice wrote:Because APODs are sometimes repeated by design.

lysandergray wrote:I'm curious, why is this post/announcement identical to ones posted on 2004 March 7 and 2002 July 28? They are perfect copies. Go to the APOD archive list and CTRL+F for "An Anomalous SETI Signal", you'll see what I mean.

rstevenson wrote:It's common practice to repost previous APODs on the weekend. Nothing weirrrrrrd about it. The APOD masters have lives; they have time off; they are volunteers. Deal with your disappointment.

Rob

neufer wrote:Ergo, at 10 light years: 10 bit/s communication would require directed communication with a 120 kw amplifier and a 42 m radio dish antenna.

NoelC wrote:

neufer wrote:Ergo, at 10 light years: 10 bit/s communication would require directed communication with a 120 kw amplifier and a 42 m radio dish antenna.

Interesting calculation. All stuff that's within our capabilities TODAY.

Out of curiosity, how "directed" is, for example, a maser beam (also doable today) vs. a radio dish antenna? Is the beam much tighter?