Orbit and dynamic origin of the recently recovered Annama's H5 chondrite

TL;DR

This study details the recovery and analysis of the Annama H4-5 chondrite meteorite, including its fall, orbit, and potential asteroid source, highlighting the dynamic processes that deliver meteorites to Earth.

Contribution

It provides a precise orbit determination and explores the meteorite's origin, suggesting a link to the 2014UR116 asteroid and the role of resonances in delivery mechanisms.

Findings

Annama meteorite experienced minimal terrestrial alteration.

The orbit was precisely determined from fireball observations.

Potential link to asteroid 2014UR116 through dynamic analysis.

Abstract

We describe the fall of Annama meteorite occurred in the remote Kola Peninsula (Russia) close to Finnish border on April 19, 2014 (local time). The fireball was instrumentally observed by the Finnish Fireball Network. From these observations the strewnfield was computed and two first meteorites were found only a few hundred meters from the predicted landing site on May 29th and May 30th 2014, so that the meteorite (an H4-5 chondrite) experienced only minimal terrestrial alteration. The accuracy of the observations allowed a precise geocentric radiant to be obtained, and the heliocentric orbit for the progenitor meteoroid to be calculated. Backward integrations of the orbits of selected near-Earth asteroids and the Annama meteoroid showed that they rapidly diverged so that the Annama meteorites are unlikely related to them. The only exception seems to be the recently discovered 2014UR116 that shows a plausible dynamic relationship. Instead, analysis of the heliocentric orbit of the meteoroid suggests that the delivery of Annama onto an Earth-crossing Apollo type orbit occurred via the 4:1 mean motion resonance with Jupiter or the nu6 secular resonance, dynamic mechanisms that are responsible for delivering to Earth most meteorites studied so far.