The last decade will be remembered by a lot of scientific events and discoveries. From the first picture of a black hole to new particles besides numerous exciting space explorations.
Check out this amazing video by secrets of the Universe!
To the best of our current knowledge, moon is the only natural “official” satellite orbiting our planet.
This, however, has often been challenged by some researchers over time who call some near-earth objects with synchronized orbits as “second moons” [1, 2].
While a number of these observations have been discarded by the scientific community, there still are objects which include temporary satellites, quasi-satellites, trojans, horseshoe orbit objects and more.
Sepharial, A. The Science of Foreknowledge: Being a Compendium of Astrological Research, Philosophy, and Practice in the East and West.; Kessinger Publishing (reprint), 1997, pp. 39–50; ISBN 1-56459-717-2
Bakich, Michael E. The Cambridge Planetary Handbook. Cambridge University Press, 2000, ISBN0-521-63280-3, p. 148