English
Related papers

Related papers: ET Probes: Looking Here as Well as There

200 papers

Arguments are reviewed in support of the hypothesis that ET would more likely send physical probes to surveil our Solar System and communicate with Earth than to communicate from afar with interstellar radio, infrared or laser beacons.…

Popular Physics · Physics 2023-07-31 John Gertz

For more than 60 years, the predominant SETI search paradigm has entailed the observation of stars in an effort to detect alien electromagnetic signals that deliberately target Earth. However, this strategy is fraught with challenges when…

Popular Physics · Physics 2023-08-02 John Gertz

The search for extraterrestrial intelligence by looking for signals from advanced technological civilizations has been ongoing for some decades. We suggest that it could possibly be made more efficient by focusing on stars from which the…

Earth and Planetary Astrophysics · Physics 2009-03-10 Shmuel Nussinov

The Defense Department and NASA are investigating the possibility that aliens are currently surveilling Earth. This aligns with some search-for-extraterrestrial-intelligence (SETI) theorists who have concluded that ET's best strategy for…

Popular Physics · Physics 2023-08-30 John Gertz

Land-based beacons, information laden probes sent into our solar system, and more distal communication nodes have each been proposed as the most likely means by which we might be contacted by ET. Each method, considered in isolation from…

Popular Physics · Physics 2021-06-09 John Gertz

One of the most interesting questions that astronomy can hope to answer is: are we alone in our Milky Way galaxy? A detection of an electromagnetic (EM) signal generated by an extraterrestrial technological intelligence, or the presence in…

Instrumentation and Methods for Astrophysics · Physics 2026-05-01 B. Zuckerman

A major aspect of the search for extraterrestrial intelligence (SETI) involves searching for electromagnetic transmissions from extraterrestrial sources, often using our own transmissions as a guide. Previous studies have suggested that…

Instrumentation and Methods for Astrophysics · Physics 2025-08-22 Pinchen Fan , Jason T. Wright , T. Joseph W. Lazio

Comparison of the total number of the radar astronomy transmissions with respect to that used for sending messages to extra-terrestrial civilizations reveals that the probability of detection of the radio signals to extraterrestrials (ETs)…

General Physics · Physics 2008-04-18 Alexander L. Zaitsev

A recently discovered group of nearby co-orbital objects is an attractive location for extraterrestrial intelligence (ETI) to locate a probe to observe Earth while not being easily seen. These near-Earth objects provide an ideal way to…

Instrumentation and Methods for Astrophysics · Physics 2019-06-17 James Benford

The main purpose of this article is to make Astronomers aware that Searches for Extraterrestrial Intelligence can be carried out by analyzing standard astronomical spectra, including those they already have taken. Simplicity is the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Ermanno F. Borra

Many hypotheses have been raised to explain the famous Fermi paradox. One of them is that self-replicating probes could have explored the whole Galaxy, including our Solar System, and that they are still to be detected. In this scenario, it…

Popular Physics · Physics 2013-10-01 M. Gillon

There is a close interrelation between Searching for Extraterrestrial Intelligence (SETI) and Messaging to Extraterrestrial Intelligence (METI). For example, the answers to the questions "Where to search" and "Where to send" are equivalent,…

Popular Physics · Physics 2015-05-13 Alexander Zaitsev

The discovery of exoplanets has both focused and expanded the search for extraterrestrial intelligence. The consideration of Earth as an exoplanet, the knowledge of the orbital parameters of individual exoplanets, and our new understanding…

Earth and Planetary Astrophysics · Physics 2019-02-06 Jason T. Wright

There have been periodic efforts in recent decades to search for extraterrestrial intelligence (SETI), especially by trying to find an extraterrestrial (ET) radio signal or other technosignature in space. Yet, no such technosignatures have…

Popular Physics · Physics 2019-07-24 Ross Davis

Within the SETI community, a school of thought holds that ET might prefer to send information physically in so-called "probes," rather than by radio or optical beacon, in effect, a message in a bottle. In this paper, a related solution to…

Popular Physics · Physics 2021-06-09 John Gertz

SETI with SKA would be by far the most powerful SETI search ever undertaken, covering enough stars with enough sensitivity to probe significantly further towards those other Earth civilisations than previous ones. This paper discusses the…

Astrophysics · Physics 2007-05-23 Alan J. Penny

The Search for Extra-terrestrial Intelligence (SETI) using radio telescopes is an area of research that is now more than 50 years old. Thus far, both targeted and wide-area surveys have yet to detect artificial signals from intelligent…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 Michael A. Garrett

The search for extraterrestrial intelligence (SETI) is a scientific endeavor which struggles with unique issues -- a strong indeterminacy in what data to look for and when to do so. This has led to attempts at finding both fundamental…

Information Theory · Computer Science 2021-07-22 Ian George , Xinan Chen , Lav R. Varshney

For centuries, astronomers have discussed the possibility of inhabited worlds - from Herschel's 18th-century observations suggesting Mars may host life, to the systematic search for technosignatures that began in the 1960s using radio…

Instrumentation and Methods for Astrophysics · Physics 2025-10-22 Beatriz Villarroel , Wesley A. Watters , Alina Streblyanska , Enrique Solano , Stefan Geier , Lars Mattsson

Deliberate and unintentional radio transmissions from Earth propagate into space. These transmissions could be detected by extraterrestrial watchers over interstellar distances. Here, we analyze the harms and benefits of deliberate and…

Popular Physics · Physics 2013-03-19 Jacob Haqq-Misra , Michael Busch , Sanjoy Som , Seth Baum
‹ Prev 1 2 3 10 Next ›