Technosignatures literature roundup

Reviewing the literature is an important part of the research process. It gives you a deeper knowledge of the field and prevents you re-inventing the wheel. As part of my open research project (currently focussed on exoplanet technosignatures) I am documenting my review of the literature by writing summaries of important concepts and interesting papers I come across.

It is a good idea to read some historical papers when getting to know a new field. Early papers put more recent studies into context and ensure that you are not relying on citations that may or may not accurately represent previous research. There are always key references that are cited over and over again. It is also interesting to see how attitudes to different ideas change over time.

After reading a few modern studies, I decided to refocus my efforts on some classic SETI papers to get a better grounding in how the field began.

This post tracks the papers I and have read together with my core “to-read” list. This list is incomplete and dynamic since there will always be new citation trails to follow as I read more papers.

For each paper I’ve read I include links to the publication followed by links to my notes and/or notebooks.

Technosignature papers read

• Kaltenegger L, Faherty JK: Past, Present and Future Stars That Can See Earth as a Transiting Exoplanet. Nature 2021, 594:505–507
  • What exoplanets can see technosignatures from Earth?
• Cocconi G, Morrison P: Searching for Interstellar Communications. Nature 1959, 184:844–846.
  • The search for interstellar communications
  • Jupyter notebook
• Bracewell RN: Communications from Superior Galactic Communities. Nature 1960, 186:670–671.
  • Communications from superior galactic communities
• Drake FD: Project Ozma. Physics Today 1961, 14:40–46.
  • Project Ozma
• Dyson FJ: Search for Artificial Stellar Sources of Infrared Radiation. Science 1960, 131:1667–1668.
  • Dyson spheres
• Schwartz RN, Townes CH: Interstellar and Interplanetary Communication by Optical Masers. Nature 1961, 190:205–208.
  • Interstellar communications by optical masers
• Kardashev NS: Transmission of Information by Extraterrestrial Civilizations. Soviet Astronomy 1964, 8:217.
  • Kardashev classification scheme for extraterrestrial civilisations
• Drake FD: THE RADIO SEARCH FOR INTELLIGENT EXTRATERRESTRIAL LIFE. In Current Aspects of Exobiology. Elsevier; 1965:323–345.
  • The Drake Equation
• Hoerner SV: The Search for Signals from Other Civilizations. Science, New Series 1961, 134:1839–1843.
  • Waiting times and longevity
• Project Cyclops: a Design Study of a System for Detecting Extraterrestrial Intelligent Life. 1972.
  • Project Cyclops Part I
  • Project Cyclops Part II
• Dixon RS: A search strategy for finding extraterrestrial radio beacons. Icarus 1973, 20:187–199.
  • A search strategy for finding extraterrestrial radio beacons
• Hart MH: Explanation for the Absence of Extraterrestrials on Earth. Quarterly Journal of the Royal Astronomical Society 1975, 16:128.
  • Why are extraterrestrials not on Earth?
• The Staff at the National Astronomy: The Arecibo message of November, 1974. Icarus 1975, 26:462–466.
  • The Arecibo message of 1974
• Oliver B M: Rationale for the water hole. Acta Astronautica 1979, 6:71–79.
  • Rationale for the water hole
• Tipler FJ: Extraterrestrial intelligent beings do not exist. Quarterly Journal of the Royal Astronomical Society 1980, 21:267–281.
  • ETI does not exist

Technosignature papers to-read

1. Lord S, Dixon R, Healy T: Project OASIS: The Design of a Signal Detector for the Search for Extraterrestrial Intelligence. 1981.
2. Sagan C: Extraterrestrial Intelligence: An International Petition. Science 1982, 218:426–426.
3. Sagan C, Newman WI: The Solipsist Approach to Extraterrestrial Intelligence. Quarterly Journal of the Royal Astronomical Society 1983, 24:113.
4. Townes CH: At what wavelengths should we search for signals from extraterrestrial intelligence? 1983, doi:https://doi.org/10.1073/pnas.80.4.1147.
5. Horowitz P, Sagan C, Horowitz P, Sagan C: Five Years of Project META: an All-Sky Narrow-Band Radio Search for Extraterrestrial Signals. ApJ 1993, 415:218.
6. Tarter J: THE SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE (SETI). 2001.
7. Tarter JC, Agrawal A, Ackermann R, Backus P, Blair SK, Bradford MT, Harp GR, Jordan J, Kilsdonk T, Smolek KE, et al.: SETI turns 50: five decades of progress in the search for extraterrestrial intelligence. 2010, 7819:781902.
8. Shuch HP: Searching for Extraterrestrial Intelligence: SETI Past, Present, and Future. Springer Berlin Heidelberg; 2011.
9. Isaacson H, Siemion APV, Marcy GW, Lebofsky M, Price DC, MacMahon D, Croft S, DeBoer D, Hickish J, Werthimer D, et al.: The Breakthrough Listen Search for Intelligent Life: Target Selection of Nearby Stars and Galaxies. PASP 2017, 129:054501.
10. Worden SP, Drew J, Siemion A, Werthimer D, DeBoer D, Croft S, MacMahon D, Lebofsky M, Isaacson H, Hickish J, et al.: Breakthrough Listen – A new search for life in the universe. Acta Astronautica 2017, 139:98–101.
11. Wright JT, Kanodia S, Lubar E: How Much SETI Has Been Done? Finding Needles in the n-dimensional Cosmic Haystack. AJ 2018, 156:260.
12. Lebofsky M, Croft S, Siemion APV, Price DC, Enriquez JE, Isaacson H, MacMahon DHE, Anderson D, Brzycki B, Cobb J, et al.: The Breakthrough Listen Search for Intelligent Life: Public Data, Formats, Reduction and Archiving. PASP 2019, 131:124505.
13. Price DC, Enriquez JE, Brzycki B, Croft S, Czech D, DeBoer D, DeMarines J, Foster G, Gajjar V, Gizani N, et al.: The Breakthrough Listen Search for Intelligent Life: Observations of 1327 Nearby Stars Over 1.10–3.45 GHz. The Astronomical Journal 2020, 159:86.
14. Sheikh SZ, Siemion A, Enriquez JE, Price DC, Isaacson H, Lebofsky M, Gajjar V, Kalas P: The Breakthrough Listen Search for Intelligent Life: A 3.95-8.00 GHz Search for Radio Technosignatures in the Restricted Earth Transit Zone. AJ 2020, 160:29.
15. Wright J: Dyson spheres. Serb Astron J 2020, doi:10.2298/SAJ2000001W.
16. Traas R, Croft S, Gajjar V, Isaacson H, Lebofsky M, MacMahon DHE, Perez K, Price DC, Sheikh S, Siemion APV, et al.: The Breakthrough Listen Search for Intelligent Life: Searching for Technosignatures in Observations of TESS Targets of Interest. AJ 2021, 161:286.

Online lists of technosignature papers

• Technosearch is an online tool tracking SETI papers since 1960.
• List of SETI papers from a Penn State graduate course in SETI. I am planning to read as many of these as possible. A talk by Jason Wright from Pennsylvania State University as part of a technosignature seminar series hosted by the Sellers Exoplanet Environments Collaboration (SEEC) at NASA’s Goddard Space Flight Center gives a nice overview of SETI research and points towards the course site for further resources. There is also some nice perspectives on some of these papers by previous students there.