30 years of cosmic fullerenes
  In 1985, "During experiments aimed at understanding the mechanisms by which
long-chain carbon molecules are formed in interstellar space and circumstellar
shells", Harry Kroto and his collaborators serendipitously discovered a new
form of carbon: fullerenes. The most emblematic fullerene (i.e. C$_{60}$
"buckminsterfullerene"), contains exactly 60 carbon atoms organized in a
cage-like structure similar to a soccer ball. Since their discovery impacted
the field of nanotechnologies, Kroto and colleagues received the Nobel prize in
1996. The cage-like structure, common to all fullerene molecules, gives them
unique properties, in particular an extraordinary stability. For this reason
and since they were discovered in experiments aimed to reproduce conditions in
space, fullerenes were sought after by astronomers for over two decades, and it
is only recently that they have been firmly identified by spectroscopy, in
evolved stars and in the interstellar medium. This identification offers the
opportunity to study the molecular physics of fullerenes in the unique physical
conditions provided by space, and to make the link with other large
carbonaceous molecules thought to be present in space : polycyclic aromatic
hydrocarbons.
