A Cloaking Device for Transiting Planets
| Autor: | Alex Teachey, David M. Kipping |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
010504 meteorology & atmospheric sciences
FOS: Physical sciences Popular Physics (physics.pop-ph) Cloaking device Physics - Popular Physics 01 natural sciences Optics Planet 0103 physical sciences Broadband Transit (astronomy) Instrumentation and Methods for Astrophysics (astro-ph.IM) 010303 astronomy & astrophysics Search for extraterrestrial intelligence 0105 earth and related environmental sciences Earth and Planetary Astrophysics (astro-ph.EP) Physics business.industry Ecliptic Extraterrestrial intelligence Cloak Astronomy Astronomy and Astrophysics Space and Planetary Science business Astrophysics - Instrumentation and Methods for Astrophysics Astrophysics - Earth and Planetary Astrophysics |
| Popis: | The transit method is presently the most successful planet discovery and characterization tool at our disposal. Other advanced civilizations would surely be aware of this technique and appreciate that their home planet's existence and habitability is essentially broadcast to all stars lying along their ecliptic plane. We suggest that advanced civilizations could cloak their presence, or deliberately broadcast it, through controlled laser emission. Such emission could distort the apparent shape of their transit light curves with relatively little energy, due to the collimated beam and relatively infrequent nature of transits. We estimate that humanity could cloak the Earth from Kepler-like broadband surveys using an optical monochromatic laser array emitting a peak power of about 30 MW for roughly 10 hours per year. A chromatic cloak, effective at all wavelengths, is more challenging requiring a large array of tunable lasers with a total power of approximately 250 MW. Alternatively, a civilization could cloak only the atmospheric signatures associated with biological activity on their world, such as oxygen, which is achievable with a peak laser power of just around 160 kW per transit. Finally, we suggest that the time of transit for optical SETI is analogous to the water-hole in radio SETI, providing a clear window in which observers may expect to communicate. Accordingly, we propose that a civilization may deliberately broadcast their technological capabilities by distorting their transit to an artificial shape, which serves as both a SETI beacon and a medium for data transmission. Such signatures could be readily searched in the archival data of transit surveys. 10 pages, 6 figures, accepted in MNRAS |
| Databáze: | OpenAIRE |
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