<i>Gaia</i> search for early-formed andesitic asteroidal crusts

Context. Andesitic meteorites are among the oldest achondrites known to date. They record volcanic events and crust formation episodes in primordial planetesimals that took place about 4.565 Myr ago. However, no analogue for these has been found asteroid population Aims. We searched spectroscopic analogues of andesitic meteorite Erg Chech 002 using Gaia DR3 spectral dataset. Methods. In order identify which asteroids have most similar spectrum 002, we first determined parameters (spectral slope Band I depth) compared them different samples meteorite. addition, performed a curve matching between data, results both methods. Results. 51 main-belt visible one 91 space-weathered spectra meteorite, corresponding 0.08 0.15% whole dataset with spectra, respectively. The best match laboratory mostly located inner main belt, while objects models show slightly more scattering across belt. Conclusions. Despite fact find potentially extremely rare. Moreover, alone is not completely diagnostic an 002-like composition. Near-infrared will be important confirm (or rule out) matches candidate population.