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.
![PDF of technoemission longevity L (top row) and starting time t of emissions (bottom row) calculated under the assumption that the unconditional PDF of t is uniform over the interval [1, 1010] yr. Panels (a)-(c) show the conditional, Eq. (9) and unconditional, Eq. (8), PDFs of L for three values of the exponent α, whereas panel (d) shows the corresponding values of L∗ such that L ≤ L∗ with 95 % probability. Panels (e) and (f) show the PDF of t calculated numerically for different values of α and (e) for Ro large enough to encompass the entire galaxy and (f) for Ro = 100 ly. Panel (g) shows the values of t∗ such that t ≤ t∗ with 95 % probability calculated for different values of Ro. -- physics.pop-ph](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/05/Technosignatures-Longevity-And.png?resize=1200%2C721&ssl=1)
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.