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tokens: 2. 2019 MMS Turbulence Campaign In the special MMS Solar Wind Turbulence Campaign, in 2019 February, the four MMS spacecraft were rearranged into a “beads on a string” configuration instead of the standard tetrahedron formation. The four spacecraft were positioned in a collinear configuration with log-spaced separation. Interspacecraft separations ranged from 30 to 200 km. Additionally, the spin axis was tilted to obtain improved electric field measurements. In this phase of the MMS orbital parameters, the formation spent a substantial period of time during each orbit in the solar wind, well beyond the bow shock. As such, the project was able to obtain a number of useful burst resolution measurements in the solar wind. The longest of those was a continuous interval of burst data lasting 5 hr, and which is analyzed in this paper, as well as in Bandyopadhyay et al. ( 2020 ). For orientation, the configuration of the four MMS spacecraft, while in the solar wind during the Turbulence Campaign, is illustrated in Figure 1 . Figure 1. Diagram of the configuration of the four MMS spacecraft near apogee, during the turbulence campaign. Note that close to apogee, when the spacecraft are in the pristine solar wind, they are aligned on the GSE Y – Z plane perpendicular to the solar wind flow. 3. MMS Data We employ 5 hr of magnetic field data from the Fluxgate Magnetometer (FGM; Russell et al. 2016 ) on board each each of the four MMS spacecraft. These are designated as MMS1, MMS2, MMS3, and MMS4. The magnetic field data are accumulated at a resolution of 128 Hz and synchronized across the formation. The orbital context is illustrated in the top panel of Figure 2 . The middle panel of Figure 2 shows the three Geocentric Solar Ecliptic (GSE) components of magnetic field recorded in this period by the MMS1 spacecraft. Figure 2. Top: location of the MMS spacecraft during this interval in bold red, along with the orbit in black. The magnetopause and bow shock are shown in light green and light blue, respectively, as estimated from OMNI data. Bottom: time series of magnetic field and PVI as defined in Equation ( 1 ), for the 5 hr interval in the solar wind. Several structures at MHD and kinetic scales (flux tubes, current sheets) can be seen. To visualize and quantify the roughness or intermittency of the magnetic field signal, we compute the partial variance of increments (PVI) of the magnetic field for this interval. The PVI, which can be computed either with two spacecraft or with a single spacecraft and the Taylor hypothesis (Chasapis et al. 2015 ; Greco et al. 2018 ) is defined aswhere here, for the multispacecraft case, the spatial lag , for the position of MMS spacecraft number I given by r I , so that that the vector increment is . The lower panel of Figure 2 shows the time series of the values of PVI computed in this way (Chhiber et al. 2018 ; Greco et al. 2018 ), namely, the two-point PVI value using spacecraft MMS2 and MMS3. The separation