Megachannel Extraterrestrial Assay Candidates: No Transmissions from Intrinsically Steady Sources

Lazio, T. Joseph W.; Tarter, Jill; Backus, P. R.

doi:10.1086/340956

Cited by 10 publications

(5 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The most popular strategies or proposals for SETI have historically centered on broadcasts by an ETI within particular bands of the electromagnetic spectrum we would consider obvious or desirable (see Sagan & Drake 1975 for examples of recommendations). However, no ostensible signatures of ETI transmissions have been detected in wide radio bands (Latham & Soderblom 1993), nor in narrow bandwidths centered on the hyperfine transition of Hi (Horowitz & Sagan 1993;Lazio et al 2002), nor convenient multiples of this frequency (Blair et al 1992;Lazio et al 2002). The same is true for different atomic and molecular transitions of other substances (e.g., H 2 O and OH: Cohen et al 1980;CO and CN: Davidge 1990;positronium: Mauersberger et al 1996).…”

Section: Philosophies Of Setimentioning

confidence: 99%

The Ĝ Infrared Search for Extraterrestrial Civilizations With Large Energy Supplies. I. Background and Justification

Wright

Mullan

Sigurd̵sson

et al. 2014

ApJ

101

View full text Add to dashboard Cite

We motivate theĜ infrared search for extraterrestrial civilizations with large energy supplies. We discuss some philosophical difficulties of SETI, and how communication SETI circumvents them. We review "Dysonian SETI", the search for artifacts of alien civilizations, and find that it is highly complementary to traditional communication SETI; the two together might succeed where either one, alone, has not. We discuss the argument of Hart (1975) that spacefaring life in the Milky Way should be either galaxy-spanning or non-existent, and examine a portion of his argument that we dub the "monocultural fallacy". We discuss some rebuttals to Hart that invoke sustainability and predict long Galaxy colonization timescales. We find that the maximum Galaxy colonization timescale is actually much shorter than previous work has found (< 10 9 yr), and that many "sustainability" counterarguments to Hart's thesis suffer from the monocultural fallacy. We extend Hart's argument to alien energy supplies, and argue that detectably large energy supplies can plausibly be expected to exist because life has potential for exponential growth until checked by resource or other limitations, and intelligence implies the ability to overcome such limitations. As such, if Hart's thesis is correct then searches for large alien civilizations in other galaxies may be fruitful; if it is incorrect, then searches for civilizations within the Milky Way are more likely to succeed than Hart argued. We review some past Dysonian SETI efforts, and discuss the promise of new mid-infrared surveys, such as that of WISE.

show abstract

Section: Philosophies Of Setimentioning

confidence: 99%

The Ĝ Infrared Search for Extraterrestrial Civilizations With Large Energy Supplies. I. Background and Justification

Wright

Mullan

Sigurd̵sson

et al. 2014

ApJ

101

View full text Add to dashboard Cite

show abstract

“…We can find the same problem with the SETI Project, which has so far produced no concrete results (Wright 2022). SETI attempts to target specific stars of G and M spectral type, have been unsuccessful as well so far (Lazio et al 2002).…”

Section: Introductionmentioning

confidence: 94%

Investigating UAP Events Using Astronomical Techniques

Teodorani

2024

Limina - The Journal of UAP Studies

View full text Add to dashboard Cite

The most important procedures about the scientific investigation of Unidentified Aerial Phenomena (UAP) using astronomy-like methods are conceptually presented and discussed, where results obtained in the past are triggering the proposal for new observational sessions using multiwavelength and multimode instruments. A special emphasis is posed on the techniques of magnetometry, photometry and spectroscopy, and on the importance of studying the variability of the phenomenon in order to try to understand the physical process that governs it, including a possible propulsion mechanism. The most important obtainable physical parameters are discussed in detail, with a particular emphasis on how they might be correlated together. The idea of placing measurement instruments at areas of the world where the phenomenon is recurrent is strongly suggested. Past monitoring campaigns at such locations are punctually mentioned together with the pertinent literature. In addition to the natural, manmade and the extraterrestrial hypotheses used to explain the nature of UAPs, the “plasma life” hypothesis is ventured too.

show abstract

“…While this may simply mean that extraterrestrial transmissions were too faint to be detected in these surveys, or that transmissions are not being made near this frequency, an alternative explanation may be that transmissions exist but only have low duty cycles. Weak evidence for the existence of such low duty cycle signals may come from the non-persistent candidate signals seen with Big Ear (Kraus, 1979;Gray & Marvel, 2001) and META (Horowitz & Sagan, 1993;Lazio et al, 2002).…”

Section: Why Send Synchronized Low Duty Cycle Signals?mentioning

confidence: 99%

Synchronized SETI—The Case for "Opposition"

Corbet

2003

Astrobiology

View full text Add to dashboard Cite

If the signals being sought in search for extraterrestrial intelligence (SETI) programs exist but are brief (for example, they are produced intermittently to conserve energy), then it is essential to know when these signals will arrive at the Earth. Different types of transmitter/receiver synchronization schemes are possible, which vary in the relative amount of effort required by the transmitter and the receiver. The case is made for a scheme that is extremely simple for the receiver: Make observations of a target when it is at maximum angular distance from the Sun (i.e., "opposition"). This strategy requires that the transmitter has accurate knowledge of the distance and proper motion of the Sun and the orbit of the Earth. It is anticipated that within the next 10-20 years it will be possible to detect directly nearby extrasolar planets of approximately terrestrial mass. Since extraterrestrial transmitters are expected to have significantly more advanced technology, it is not unreasonable to expect that they would be able to detect the presence of the Earth and measure its orbit at even greater distances. This strategy is simple to implement, and opposition is also typically the time when observations are easiest to make. Limited opposition surveys contained in a number of all-sky surveys have already been performed. However, full-sky opposition surveys are best suited to detectors with very large fields of view.

show abstract

Megachannel Extraterrestrial Assay Candidates: No Transmissions from Intrinsically Steady Sources

Cited by 10 publications

References 21 publications

The Ĝ Infrared Search for Extraterrestrial Civilizations With Large Energy Supplies. I. Background and Justification

The Ĝ Infrared Search for Extraterrestrial Civilizations With Large Energy Supplies. I. Background and Justification

Investigating UAP Events Using Astronomical Techniques

Synchronized SETI—The Case for "Opposition"

Contact Info

Product

Resources

About