6 research outputs found
BepiColombo’s Cruise Phase: Unique Opportunity for Synergistic Observations
The investigation of multi-spacecraft coordinated observations during the cruise phase of BepiColombo (ESA/JAXA) are reported, with a particular emphasis on the recently launched missions, Solar Orbiter (ESA/NASA) and Parker Solar Probe (NASA). Despite some payload constraints, many instruments onboard BepiColombo are operating during its cruise phase simultaneously covering a wide range of heliocentric distances (0.28 AU–0.5 AU). Hence, the various spacecraft configurations and the combined in-situ and remote sensing measurements from the different spacecraft, offer unique opportunities for BepiColombo to be part of these unprecedented multipoint synergistic observations and for potential scientific studies in the inner heliosphere, even before its orbit insertion around Mercury in December 2025. The main goal of this report is to present the coordinated observation opportunities during the cruise phase of BepiColombo (excluding the planetary flybys). We summarize the identified science topics, the operational instruments, the method we have used to identify the windows of opportunity and discuss the planning of joint observations in the future.</p
Moonraker: enceladus multiple flyby mission
Stars and planetary system
On the Statistical Properties of Turbulent Energy Transfer Rate in the Inner Heliosphere
The transfer of energy from large to small scales in solar wind turbulence is
an important ingredient of the longstanding question about the mechanism of the
interplanetary plasma heating. Previous studies have shown that
magnetohydrodynamic (MHD) turbulence is statistically compatible with the
observed solar wind heating as it expands in the heliosphere. However, in order
to understand which processes contribute to the plasma heating, it is necessary
to have a local description of the energy flux across scales. To this aim, it
is customary to use indicators such as the magnetic field partial variance of
increments (PVI), which is associated with the local, relative, scale-dependent
magnetic energy. A more complete evaluation of the energy transfer should also
include other terms, related to velocity and cross-helicity. This is achieved
here by introducing a proxy for the local, scale dependent turbulent energy
transfer rate epsilon_Dt(t), based on the third-order moment scaling law for
MHD turbulence. Data from Helios 2 are used to determine the statistical
properties of such a proxy in comparison with the magnetic and velocity fields
PVI, and the correlation with local solar wind heating is computed. PVI and
epsilon_Dt(t) are generally well correlated, however epsilon_Dt(t) is a very
sensitive proxy that can exhibit large amplitude values, both positive and
negative, even for low amplitude peaks in the PVI. Furthermore, epsilon_Dt(t)
is very well correlated with local increases of temperature when large
amplitude bursts of energy transfer are localized, thus suggesting an important
role played by this proxy in the study of plasma energy dissipation.Comment: This is a pre-print of an article to be published in Solar Physics.
The final authenticated version will be soon available onlin