Related Experiment Video
Updated: Dec 23, 2025
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
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A Galactic centre gravitational-wave Messenger.
Marek Abramowicz1,2,3, Michał Bejger2,4, Éric Gourgoulhon5
1Physics Department, University of Gothenburg, 412-96, Göteborg, Sweden.
Scientific Reports
|April 29, 2020
Summary
Highly developed extraterrestrial civilizations may place probes near Sagittarius A* (Sgr A*). These probes would generate detectable gravitational waves, offering a unique signal of artificial origin.
Area of Science:
- Astrophysics
- Astrobiology
- Gravitational Wave Astronomy
Background:
- The Universe's conditions suggest rare occurrences of advanced life.
- The Milky Way's galactic center, hosting Sagittarius A* (Sgr A*), is a unique location for potential extraterrestrial activity.
Purpose of the Study:
- To investigate the astrophysical possibility of advanced civilizations utilizing Sagittarius A*.
- To determine if such utilization would produce detectable gravitational wave signals.
Main Methods:
- Modeling a Jupiter-mass probe in orbit around Sgr A*.
- Calculating the frequency and power of emitted gravitational waves based on black hole spin.
Main Results:
- A probe in a retrograde orbit around Sgr A* emits gravitational waves at 0.63-1.07 mHz with a power of 2.7×10^36-2.0×10^37 erg/s.
- Stellar energy output can sustain such a probe's orbit for a billion years against decay.
Conclusions:
- Placing and sustaining an artificial probe near Sgr A* is astrophysically feasible.
- Such a probe would emit a continuous, artificial gravitational wave signal detectable by LISA-type instruments.
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