  Comet Interceptor is an ESA F-class mission expected to launch in 2028 on the
same launcher as ESA's ARIEL mission. Comet Interceptor's science payload
consists of three spacecraft, a primary spacecraft that will carry two smaller
probes to be released at the target. The three spacecraft will fly-by the
target along different chords, providing multiple simultaneous perspectives of
the comet nucleus and its environment. Each of the spacecraft will be equipped
with different but complementary instrument suites designed to study the far
and near coma environment and surface of a comet or interstellar object (ISO).
The primary spacecraft will perform a fly-by at ~1000 km from the target. The
two smaller probes will travel deeper into the coma, closer to the nucleus. The
mission is being designed and launched without a specific comet designated as
its main target. Comet Interceptor will travel to the Sun-Earth L2 Lagrangian
point with ARIEL and wait in hibernation until a suitable long-period comet
(LPC) is found that will come close enough to the Sun for the spacecraft to
maneuver to an encounter trajectory. To prepare for all eventualities, the
science team has assembled a preliminary set of backup targets from the known
Jupiter family comets, where a suitable fly-by trajectory can be achieved
during the nominal mission timeline (including the possibility of some launch
delay). To better prioritize this list, we are releasing our potential backup
targets in order to solicit the planetary community's help with observations of
these objects over future apparitions and to encourage publication of archival
data on these objects.
