I need to stop blogging for about a week, and I want to leave this post on the top of the front page while I'm gone.
The Voyager spacecraft's "pale blue dot" image, and Carl Sagan's commentary upon it, have been the subject of many video tributes; the one embedded above is my favorite because of the juxtaposition of so many classic film clips accompanying the spoken text.
Voyager carries a golden "phonograph record" embedded with basic information about our solar system and human biology, which most people understand as an attempt to initiate contact with other, extraterrestrial, intelligent species. It's really nothing of the sort, because it didn't even exit the solar system until 2012, and after another 40,000 years it will still be 1.6 light-years from the nearest other star. So the artifacts on Voyager are best viewed as a time capsule of our current existence rather than a communication device.
Traversing cosmic distances requires faster speeds than can (currently) be achieved by physical objects. Which leads us to a consideration of radio transmissions. Here's the opening scene from the movie "Contact," which depicts radio signals from earth penetrating out into space:
The further out you go, of course, the older are the signals you/[or an alien] could potentially hear/detect. The viewpoint pulls back beyond our solar system until it is even outside our galaxy.
I had always been impressed by that. Until... several weeks ago I encountered this spectacular image at Cliff Pickover's Reality Carnival:
I had to compress the image to stay within the limits of my bloghost, so I don't know if the embed above will be clickable to supersize. If not, you can view the original here in all its glory*. At the right bottom is a box, enlarged from the right center of the image, showing another "pale blue dot."
But this time, that blue dot is not Earth, as it is in the Sagan/Voyager story, but rather a representation of a sphere of a diameter of 200 light-years. That's the total distance that emissions from earth have traveled since our development of the technology.
I can't get this image out of my head. That little dot is the maximal extent of human influence in our galaxy - and there are over a hundred billion such galaxies in the known universe.
The human mind isn't capable of processing such realities. At least mine isn't.
Now I'm off for a week or so.
p.s. - see also Stephen Hawking's thoughts on communication with alien intelligent life.
*the text at the bottom left reads "Thanks to Nick Risinger for the artist's conception of the Milky Way." Image taken from here.
Unfortunately, we now think that all our radio signals submerge into the general background within a lightyear or two, and so they become undetectable. Nobody's going to find us that way unless a probe passes relatively nearby. This is not impossible, just terribly unlikely.
ReplyDeleteThoroughly enjoying this blog - you've earned some time off! Enjoy.
ReplyDeleteWell, yes - Voyager will act as a time capsule...until the Klingons blow it to pieces!
ReplyDeleteUummmmm ... it hasn't it only been a bit over 100 years since radio was invented, not 200 years? Never mind that the first broadcasts were not very powerful either..
ReplyDeleteYes, but a radius of 100 light years gives a diameter of 200 ;-)
DeleteHoping you enjoy your time away, 'Stan, and I'm sure you've earned the break. It must be a lot of work finding stuff for your blog, and I'm sure that I'm not the only person out here who looks at it on a daily basis. There's always something to learn or just amaze.
ReplyDeleteYes, the size of space astounds.
That they have not contacted us, is evidence enough for me that, whatever life is 'out there', it is, for that reason, intelligent
ReplyDeleteBigger than anything our miniscule little minds can possibly fathom- and yet many of our best and brightest (scientists) will tell you straight to your face that we are the highest culmination of all that is...
ReplyDeleteAs if its very vastness has rendered them impotent of considering something beyond their backyard other than empty streets.
Who are you talking about? I really don't think the view that humans are somehow the apogee of progress is very prevalent in scientific circles.
DeleteYou needn't go further than St. Carl himself who rigorously and enthusiastically attacked and ridiculed whoever dared entertain the very notion that anyone or anything smarter than he could possibly be visiting our "pale blue dot."
DeleteCan you point us to one of these attacks? I just want to judge what he said for myself.
DeleteIt seems weird that he would just reject the idea of intelligent life forms visiting Earth out of hand, given that he was one of the early instigators of the SETI program and one of the few scientists who wanted to investigate UFO claims seriously. Being a scientist he also wanted some evidence though, rather than rely only on eyewitness accounts. That seems perfectly reasonable to me.
Carl Sagan: "Extraordinary Claims Require Extraordinary Evidence": http://www.youtube.com/watch?v=mRaXvPQ-ayk
DeleteHe was very much for the possibility of life out there, somewhere (eg- SETI). But he was an ardent UFO debunker- anyone even vaguely familiar with his career would be aware of that. Top scientists Do Not publicly admit to UFO's being intelligently controlled vehicles of ET origin- it immediately closes down their research funding and ends careers (eg- Dr. John E. Mack).
ReplyDeleteSupposedly, Sagan met with astrophysicist Dr. Allen Hyneck (former Project Bluebook head investigator and skeptic turned "believer") to privately consider the very real possibility of their existence and origins.
http://www.prweb.com/releases/2010/05/prweb3966374.htm
The line between debunking and asking for evidence isn't all that clear to me, to be honest.
DeleteI'd like to emphasize the "supposedly" in your comment. I'm not entirely convinced of the reliability of the information in this article.
It was written by someone at ZlandCommunications News Network (which is entirely dedicated to UFOs) based on the account of Paola Harris (who is a journalist in the field of UFOs) of her recollection of an interview with someone to whom Sagan "supposedly" made this amazing revelation backstage at a TV show.
So do I believe this, or do I believe that Sagan actually believed what he said publicly? I personally favor the second option.
Dan- Yes, we are both in 100% agreement that what Sagan said in public is what counts! I've only emphasized that, if anything. He very much was a leading skeptic/debunker- don't profess to know if he ever thought otherwise...
Deletehttp://www.afterdisclosure.com/2012/06/carl-sagan-theyre-everywhere-but-here.html
I'm glad we agree! It's just that I didn't understand your point this way at first.
DeleteIf by "our best and brightest will tell you straight to your face that we are the highest culmination of all that is" you meant "scientists are skeptical of claims of alien abductions and UFO sightings", I totally agree! I don't think it's such a bad thing though, since credulous scientists are slightly useless.
That's why people with any any interest in the matter should acquaint themselves with Dr. Allen Hyneck.
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