1. Signal aus dem All empfangen ?
- Ersteller Sir Ulli
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Sir Ulli
Grand Admiral Special
Amerikanische Wissenschaftler empfingen geheimnisvolle Botschaft
Mit einem Netz von riesigen, besonders empfindlichen Radio-Teleskopen horchen die Alien-Jäger der SETI nach Nachrichten aus dem Weltraum. Sind sie jetzt fündig geworden?
Von HANS BEWERSDORFF
Sie klingen wie verzerrte Radiowellen und wurden in den letzten 19 Monaten schon drei Mal aufgefangen – seltsame Nachrichten aus dem All. Wissenschaftler halten es für möglich: Dies ist die erste Botschaft von Außerirdischen an uns Menschen.
Die Signale kommen immer aus derselben Himmelsregion zwischen den Sternbildern Fische und Widder. Sie wurden von den Teleskopen der SETI (Search for Extraterrestrial Intelligence), der amerikanischen Behörde für die Suche nach außerirdischem Leben, aufgefangen.
Die Wissenschaftler gaben den Signalen die Bezeichnung SHGb02+14a. Die Signale sind der beste je gefundene Kandidat für einen Kontakt zu intelligenten Aliens.
Der Forscher Eric Korpela von der Alien-Behörde SETI: „Wir suchen fieberhaft nach natürlichen Ursachen für die Effekte, aber wir finden sie nicht.“
Dan Wertheimer von der Berkeley Universität in Kalifornien ist zuversichtlich: „Es ist das interessanteste Signal, das SETI je gefunden hat.“
Die Forscher wollen das Phänomen weiter beobachten.
Full Story
weitere Infos hier und hier
mfg
Sir Ulli
Mit einem Netz von riesigen, besonders empfindlichen Radio-Teleskopen horchen die Alien-Jäger der SETI nach Nachrichten aus dem Weltraum. Sind sie jetzt fündig geworden?
Von HANS BEWERSDORFF
Sie klingen wie verzerrte Radiowellen und wurden in den letzten 19 Monaten schon drei Mal aufgefangen – seltsame Nachrichten aus dem All. Wissenschaftler halten es für möglich: Dies ist die erste Botschaft von Außerirdischen an uns Menschen.
Die Signale kommen immer aus derselben Himmelsregion zwischen den Sternbildern Fische und Widder. Sie wurden von den Teleskopen der SETI (Search for Extraterrestrial Intelligence), der amerikanischen Behörde für die Suche nach außerirdischem Leben, aufgefangen.
Die Wissenschaftler gaben den Signalen die Bezeichnung SHGb02+14a. Die Signale sind der beste je gefundene Kandidat für einen Kontakt zu intelligenten Aliens.
Der Forscher Eric Korpela von der Alien-Behörde SETI: „Wir suchen fieberhaft nach natürlichen Ursachen für die Effekte, aber wir finden sie nicht.“
Dan Wertheimer von der Berkeley Universität in Kalifornien ist zuversichtlich: „Es ist das interessanteste Signal, das SETI je gefunden hat.“
Die Forscher wollen das Phänomen weiter beobachten.
Full Story
weitere Infos hier und hier
mfg
Sir Ulli
Sir Ulli
Grand Admiral Special
habe ja vermutet das da noch was kommt...
Reports of SETI@home Extraterrestrial Signal Highly Exaggerated
by Amir Alexander
Reports of SETI@home Extraterrestrial Signal Highly Exaggerated by the Planetary Society
btw Exaggerated bedeutet soviel wie Übertrieben
Sir Ulli
Reports of SETI@home Extraterrestrial Signal Highly Exaggerated
by Amir Alexander
Reports of SETI@home Extraterrestrial Signal Highly Exaggerated by the Planetary Society
btw Exaggerated bedeutet soviel wie Übertrieben
Sir Ulli
Sir Ulli
Grand Admiral Special
und es geht weiter
Story by
Seth Shostak Senior Astronomer
September 2, 2004
A recent (September 1) article in New Scientist magazine, entitled “ Mysterious signals from 1000 light years away,” implies that the Berkeley SETI@home project has uncovered a very convincing candidate signal that might be the first strong evidence for extraterrestrial intelligence.
Alas, this story is misleading. According to Dan Werthimer, who heads up the Berkeley SERENDIP SETI project, this is a case of a reporter failing to understand the workings of their search. He says that misquotes and statements taken out of context give the impression that his team is exceptionally impressed with one of the many candidate signals, SHGb02+14a, uncovered using the popular SETI@home software. They are not.
This signal has been found twice by folks using the downloadable screen saver. That fact resulted in the Berkeley team putting it on their list of ‘best candidates’. Keep in mind that SETI@home produces 15 million signal reports each day. How can one possibly sort through this enormous flood of data to sift out signals that might be truly extraterrestrial, rather than merely noise artifacts or man-made interference?
The scheme used is simple in principle (although the technical details are complex): SETI@home data come from a receiver on the Arecibo radio telescope that is incessantly panning the sky, riding “piggyback” on other astronomical observations. Every few seconds, it sweeps another patch of celestial real estate, and records data covering many millions of frequency channels. Some of these data are then distributed for processing by the screen saver. By chance, the telescope will sweep the same sky patch every six months or so. If a signal is persistent – that is to say, it shows up more than once when the telescope is pointed at the same place, and at the same frequency (after correction for shifts due to the motion of the Earth) – then it becomes a candidate. Of course, being persistent doesn’t mean that the source is always on, only that it is found multiple times.
In February of this year, Werthimer and his colleagues took a list of two hundred of the best SETI@home candidate signals to Arecibo and deliberately targeted that mammoth antenna in the directions to which the scope was pointed when they were found. Once subjected to this closer inspection, all but one of these signals failed to show. That disqualifies them from being claimed as true detections of a persistent signal. The one that was found again, SHGb02+14a (the subject of the New Scientist article), will no doubt be observed yet again, but according to Paul Horowitz, who heads up the Harvard SETI efforts, the statistics of noise make it fairly likely that at least one of the candidates observed in February would reappear, even if all these signals were simply due to receiver fluctuations.
The article remarks on the strong drift of this signal, which it describes as puzzling. Of course, many terrestrial sources of interference, and in particular telecommunication satellites, show strong drifts due to changing Doppler effects as they wheel across the sky. (Incidentally, the technically inclined will want to note drift due to a planet rotating like Earth would be 0.15 Hz/sec, not the 1.5 Hz/sec mentioned in the magazine.) As for the distance of 1000 light-years claimed in the article’s title, there is clearly no evidence supporting this number, other than the lack of known nearby stars in the beam.
The bottom line is that an experiment like SETI@home always has a candidate list, a table of those signals that look most promising. Indeed, you can find the current versions of this list on their web site. However, there is a great deal of difference between a candidate, and a convincing signal. If any of the major SETI experiments being run by the SETI Institute, by the Berkeley group, the folks at Harvard, or the Australians or Italians, discovers a signal that they think is of extraterrestrial origin, they will immediately take steps to confirm this, both with their own scientists and with observers at other organizations. You will find information about it on their web sites, and in multiple media outlets.
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
Has Seti@home found a Signal
aber einige Fragen bleiben unbeantwortet
von dem Ursprungsthread Newscientist.com
war die erste Seite die das gepostet hat
wie kommen die an die Namen, beide haben kein Profile at Seti@home Classic für diese WU SHGb02+14a
da bleibt nur Inhouse Information von Berkeley
da bleiben einige Fragen unbeantwortet, finde ich... die Dementis kamen mir zu schnell und zu konzentriert.
Sir Ulli
Story by
Seth Shostak Senior Astronomer
September 2, 2004
A recent (September 1) article in New Scientist magazine, entitled “ Mysterious signals from 1000 light years away,” implies that the Berkeley SETI@home project has uncovered a very convincing candidate signal that might be the first strong evidence for extraterrestrial intelligence.
Alas, this story is misleading. According to Dan Werthimer, who heads up the Berkeley SERENDIP SETI project, this is a case of a reporter failing to understand the workings of their search. He says that misquotes and statements taken out of context give the impression that his team is exceptionally impressed with one of the many candidate signals, SHGb02+14a, uncovered using the popular SETI@home software. They are not.
This signal has been found twice by folks using the downloadable screen saver. That fact resulted in the Berkeley team putting it on their list of ‘best candidates’. Keep in mind that SETI@home produces 15 million signal reports each day. How can one possibly sort through this enormous flood of data to sift out signals that might be truly extraterrestrial, rather than merely noise artifacts or man-made interference?
The scheme used is simple in principle (although the technical details are complex): SETI@home data come from a receiver on the Arecibo radio telescope that is incessantly panning the sky, riding “piggyback” on other astronomical observations. Every few seconds, it sweeps another patch of celestial real estate, and records data covering many millions of frequency channels. Some of these data are then distributed for processing by the screen saver. By chance, the telescope will sweep the same sky patch every six months or so. If a signal is persistent – that is to say, it shows up more than once when the telescope is pointed at the same place, and at the same frequency (after correction for shifts due to the motion of the Earth) – then it becomes a candidate. Of course, being persistent doesn’t mean that the source is always on, only that it is found multiple times.
In February of this year, Werthimer and his colleagues took a list of two hundred of the best SETI@home candidate signals to Arecibo and deliberately targeted that mammoth antenna in the directions to which the scope was pointed when they were found. Once subjected to this closer inspection, all but one of these signals failed to show. That disqualifies them from being claimed as true detections of a persistent signal. The one that was found again, SHGb02+14a (the subject of the New Scientist article), will no doubt be observed yet again, but according to Paul Horowitz, who heads up the Harvard SETI efforts, the statistics of noise make it fairly likely that at least one of the candidates observed in February would reappear, even if all these signals were simply due to receiver fluctuations.
The article remarks on the strong drift of this signal, which it describes as puzzling. Of course, many terrestrial sources of interference, and in particular telecommunication satellites, show strong drifts due to changing Doppler effects as they wheel across the sky. (Incidentally, the technically inclined will want to note drift due to a planet rotating like Earth would be 0.15 Hz/sec, not the 1.5 Hz/sec mentioned in the magazine.) As for the distance of 1000 light-years claimed in the article’s title, there is clearly no evidence supporting this number, other than the lack of known nearby stars in the beam.
The bottom line is that an experiment like SETI@home always has a candidate list, a table of those signals that look most promising. Indeed, you can find the current versions of this list on their web site. However, there is a great deal of difference between a candidate, and a convincing signal. If any of the major SETI experiments being run by the SETI Institute, by the Berkeley group, the folks at Harvard, or the Australians or Italians, discovers a signal that they think is of extraterrestrial origin, they will immediately take steps to confirm this, both with their own scientists and with observers at other organizations. You will find information about it on their web sites, and in multiple media outlets.
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
Has Seti@home found a Signal
aber einige Fragen bleiben unbeantwortet
von dem Ursprungsthread Newscientist.com
war die erste Seite die das gepostet hat
wie kommen die an die Namen, beide haben kein Profile at Seti@home Classic für diese WU SHGb02+14a
da bleibt nur Inhouse Information von Berkeley
da bleiben einige Fragen unbeantwortet, finde ich... die Dementis kamen mir zu schnell und zu konzentriert.
Sir Ulli
Major J
Admiral Special
Falscher Alarm ist auch ein Alarm. 
Sir Ulli
Grand Admiral Special
SETI@Home Chief Scientist Dan Werthimer Says Sorry, Wrong Number
Planetary Radio Show for September 20, 2004
Airdate: September 20, 2004
Play time: 28:50
The rumors of a message from an extraterrestrial intelligence have been greatly exaggerated, according to Dan Werthimer. He updates us on this and lots of other recent developments, including a recent SETI summit at Harvard. Emily Lakdawalla is in sync with moons that always face one way, and Bruce Betts has another What's Up! look at the sky, along with his latest space trivia contest.
ein Interview mit Dan Werthimer Planetary Radio Show for September 20, 2004
mfg
Sir Ulli
Planetary Radio Show for September 20, 2004
Airdate: September 20, 2004
Play time: 28:50
The rumors of a message from an extraterrestrial intelligence have been greatly exaggerated, according to Dan Werthimer. He updates us on this and lots of other recent developments, including a recent SETI summit at Harvard. Emily Lakdawalla is in sync with moons that always face one way, and Bruce Betts has another What's Up! look at the sky, along with his latest space trivia contest.
ein Interview mit Dan Werthimer Planetary Radio Show for September 20, 2004
mfg
Sir Ulli
