Much of our knowledge about the large-scale structure and variations of
the solar wind, interplanetary magnetic field (IMF), transients (coronal
mass ejections, shocks) and energetic particles in the inner heliosphere
(< 2 AU) was gained from multi-spacecraft in-situ measurements,
especially from missions such as Helios and STEREO as well as
conjunctions between spacecraft at various planets. We have also gained
some knowledge of structures and variability in the interplanetary space
associated with turbulence, waves and instabilities on much smaller
scales thanks to ACE, Wind and ARTEMIS as well as MMS, while their
properties on intermediate (meso) scales is yet mostly unknown. The aim
of this session is to discuss progress in our understanding of CMEs,
CIRs, shocks, SEPs, the IMF and solar wind made thanks to
multi-spacecraft measurements on various scales ranging from a fraction
of an earth radius to 1 AU and the way forward. This session invites
abstracts related to analyses and simulations of multi-spacecraft
measurements in the inner heliosphere. It is especially interested in
in-situ measurements made possible by STEREO (which will be within 60
degrees of the Sun-Earth line by the end of 2020), Solar Probe, Solar
Orbiter and missions near L1, planetary missions (MESSENGER,
BepiColombo, MAVEN) as well as future missions, concepts and
instrumentation to investigate the various scales in interplanetary
space.