The bodies that have a p-value smaller than 5% pass through the second calibration test. The resulting p-value shows us how likely it is to obtain a peak as large as the largest peak found in the data if there was only noise in the data. The first procedure is to run 10000 Monte Carlo simulations on white noise using the same time-sampling as the real data. Since this technique always finds periodic fluctuations that could be spurious because of residual noise, we perform some statistical tests to determine the probability of fake detection and the relevance of the signal found. The result is a map of the frequency power that indicates the goodness of data fitting. Then, using a Generalized Lomb-Scargle periodogram (see and references therein), we run a period search on every sequence in order to find a signal that would represent the period and amplitude of the system's wobbling. This selection results in a sample of a bit more than 30000 objects. We select the asteroids with at least 10 values of residuals that are consecutive in time or anyway spanning a limited time range. Our approach starts by averaging the residuals to orbital fits over each transit in the focal plane. Hence, using a large number of bodies in DR3 data with even better precision than in previous releases, we aim to search for astrometric asteroid binaries. Data Release 3 (DR3) provides new data for more than 150.000 asteroids, 10 times more than in Gaia DR2. The Gaia mission provided to the scientific community astrometric solutions at an unprecedented precision. As predicted way before the launch of the Gaia satellite, the high accuracy astrometric data could be used to find binary asteroids currently out of reach of detection. The same approach becomes possible for asteroids, for the first time thanks to Gaia astrometry. In binary star research, companions are revealed by astrometry when the motion of a star around the common barycentre is measured (wobbling). In that range, the use of highly accurate astrometry could be promising. But still, a whole range of separation and size ratios is out of reach, where asteroids are too faint for high-resolution imaging, too far for radar, or do not provide a good signature in photometry. Recently in 2021, it was the first time that a stellar occultation provided the discovery of a companion asteroid by two independent events. After that, more than 450 asteroids with satellites were discovered in the Solar System, almost 80% of them with orbits up to Jupiter, using many other observation techniques such as radar, and direct imaging from the ground and space. (385186) 1994 AW1 was the first known asteroid with a satellite, discovered in 1994 using photometric lightcurve, the most successful technique used for this purpose.
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