Related papers: Prior Indigenous Technological Species
Terrestrial planetary systems may exist around nearby stars as the Earth-sized counterparts to the many giant planets already discovered within the solar neighborhood. In this chapter we first discuss the numerous techniques which have been…
Exoplanet hunting efforts have revealed the prevalence of exotic worlds with diverse properties, including Earth-sized bodies, which has fueled our endeavor to search for life beyond the Solar System. Accumulating experiences in…
We carry out 3-D numerical simulations to assess the penetration and bombardment effects of Solar Energetic Particles (SEPs), i.e. high-energy particle bursts during large flares and superflares, on ancient and current Mars. We demonstrate…
The goal of the Search for Extraterrestrial Intelligence (SETI) is to quantify the prevalence of technological life beyond Earth via their "technosignatures". One theorized technosignature is narrowband Doppler drifting radio signals. The…
The existence of intelligent extraterrestrial life forms among the thousands of billions of galaxies that dance in the Universe is beyond doubt. Meeting with one of them is only a matter of time. SETI (Search for Extraterrestrial…
Technosignatures refer to observational manifestations of technology that could be detected through astronomical means. Most previous searches for technosignatures have focused on searches for radio signals, but many current and future…
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…
The probability of detecting technosignatures (i.e. evidence of technological activity beyond Earth) increases with their longevity, or the time interval over which they manifest. Therefore, the assumed distribution of longevities has some…
One of the beneficial outcomes of searching for life in the Universe is that it grants greater awareness of our own problems here on Earth. Lack of contact with alien beings to date might actually comprise a null "signal" pointing humankind…
The discovery of inhabited exoplanets hinges on identifying biosignature gases. JWST can reveal biosignature gases, though current discoveries have yet to evidence life. The central challenge is attribution: how can we confidently identify…
The Astro2020 report outlines numerous recommendations that could significantly advance technosignature science. Technosignatures refer to any observable manifestations of extraterrestrial technology, and the search for technosignatures is…
For over 50 years, astronomers have searched the skies for evidence of electromagnetic signals from extraterrestrial civilizations that have reached or surpassed our level of technological development. Although often overlooked or given as…
In the modern search for life elsewhere in the Universe, we are broadly looking for the following: the planets similar to Earth - physical indicators of habitability, and the manifestation of life - the biological signatures. A biosignature…
The search for life beyond the solar system is a central goal in exoplanetary science. Exoplanet surveys are increasingly detecting potentially habitable exoplanets and large telescopes in space and on ground are aiming to detect possible…
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…
Recent discoveries of potentially habitable exoplanets have ignited the prospect of spectroscopic investigations of exoplanet surfaces and atmospheres for signs of life. This chapter provides an overview of potential surface and temporal…
We review the field of exoplanetary biosignatures with a main focus upon atmospheric gas-phase species. Due to the paucity of data in Earth-like planetary atmospheres a common approach is to extrapolate knowledge from the Solar System and…
The absence of planets interior to Mercury continues to puzzle terrestrial planet formation models, particularly when contrasted with the relatively high derived occurrence rates of short-period planets around Sun-like stars. Recent work…
As we discover numerous habitable planets around other stars in the Milky Way galaxy, including the nearest star, Proxima Centauri, one cannot help but wonder why have we not detected evidence for an advanced alien civilization as of yet.…
The Search for Extraterrestrial Intelligence (SETI) is a research activity that started in the late 1950s, predating the arrival of "Big History" and "Astrobiology" by several decades. Many elements first developed as part of the original…