Astroengineering

Astroengineering is engineering at astronomical scale, i.e. at planetary, stellar, stellar system, galactic or even larger scale. It is clearly a form of megascale engineering. An example is the hypothetical Dyson sphere.

Applications

Typical megastructures that could hypothetically be produced by astroengineering include Dyson spheres, ringworlds, Alderson disks, Banks' Orbitals, Matrioshka brains, stellar engines such as Shkadov thrusters, and other artifacts produced by Type II and Type III civilizations on the Kardashev scale.

In a 2005 paper, Luc Arnold proposed a means of detecting smaller, though still megascale, artifacts from their distinctive transit light curve signature.[1]

Some applications are becoming more relevant to our time period as advances in technology progress. Astroengineering projects like orbital towers (or orbital elevators) are becoming more technically feasible due to such technological advances.[2]

It was suggested that an advanced civilization could use a pulsar for signalling through the modulation of its light curve.[3] Such an application would require construction of a large scale structure (modulator) around the pulsar. Possible observable effects are missing pulses and an increase in thermal radiation due to the secondary emission from the modulator. Missing pulses (pulse nulling) has been observed in many pulsars and is usually attributed to natural phenomena.[4] However, a statistical study of the missing pulse sequences revealed that nulling is not random in many pulsars.[5] This poses a problem of distinguishing the natural modulation from artificial one.

Changing the cycle parameters of variable stars (Cepheids) is theoretically possible by firing a high-energy neutrino beam into the star's core. This effect can be used as a way to transmit information and create "galactic Internet".[6][7] The rate of transmission is very slow, though, about 180 bits per year.

Limiting factors

Resources is the one of the limiting factors preventing advances in astroengineering. Since astroengineering revolves around creating megastructures that could be millions of kilometers long, obtaining materials would require more than Earth's resources.

Even if resources become more abundant from other planets and planetary systems, energy limits what engineers would be able to accomplish. Creating large-scale structures requires large amounts of energy. Potential energy sources which would be used by a Type II or Type III civilization on the Kardashev scale include:

In fiction

Astroengineering has been described in many works of fiction:

Gallery

See also

References

  1. Arnold, Luc F. A. (2005). "Transit Light‐Curve Signatures of Artificial Objects" (PDF). The Astrophysical Journal 627: 534–539. doi:10.1086/430437. Retrieved January 6, 2009.
  2. Colin R., McInnes (March–April 2005). "Dynamics of a particle moving along an orbital tower" (PDF). Journal of Guidance, Control and Dynamics 28 (2): 380–382. ISSN 0731-5090. The concept of an orbital tower has been discussed in the literature by many authors over a number of years. Although the concept is clearly futuristic, interest has recently been revived as a result of advances in materials science.
  3. Chennamangalam, Jayanth; Siemion, Andrew P.V.; Lorimer, D.R.; Werthimer, Dan (January 2015). "Jumping the energetics queue: Modulation of pulsar signals by extraterrestrial civilizations". New Astronomy 34: 245–249. doi:10.1016/j.newast.2014.07.011.
  4. Wang, N.; Manchester, R. N.; Johnston, S. (21 May 2007). "Pulsar nulling and mode changing". Monthly Notices of the Royal Astronomical Society 377 (3): 1383–1392. doi:10.1111/j.1365-2966.2007.11703.x.
  5. Redman, Stephen L.; Rankin, Joanna M. (21 May 2009). "On the randomness of pulsar nulls". Monthly Notices of the Royal Astronomical Society 395 (3): 1529–1532. doi:10.1111/j.1365-2966.2009.14632.x.
  6. Choi, Charles (9 September 2008). "'Galactic internet' proposed". Nature. doi:10.1038/news.2008.1091.
  7. http://arxiv.org/abs/0809.0339v2
  8. Dyson, Freeman J. (1966). Marshak, R. E., ed. "The Search for Extraterrestrial Technology". Perspectives in Modern Physics (New York: John Wiley & Sons).
  9. Newman, Phil (2001-10-22). "New Energy Source "Wrings" Power from Black Hole Spin". NASA. Archived from the original on 2008-02-09. Retrieved 2008-02-19.
  10. Schutz, Bernard F. (1985). A First Course in General Relativity. New York: Cambridge University Press. pp. 304, 305. ISBN 0-521-27703-5.
  11. Kardashev, Nikolai. "On the Inevitability and the Possible Structures of Supercivilizations", The search for extraterrestrial life: Recent developments; Proceedings of the Symposium, Boston, MA, June 18–21, 1984 (A86-38126 17-88). Dordrecht, D. Reidel Publishing Co., 1985, p. 497–504.
  12. "Star Trek: The Next Generation Relics (TV episode 1992) - IMDb". IMDB. Retrieved 2011-11-21.

Further reading

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