  We report the observations of an electron vortex magnetic hole corresponding
to a new type of coherent structures in the magnetosheath turbulent plasma
using the Magnetospheric Multiscale (MMS) mission data. The magnetic hole is
characterized by a magnetic depression, a density peak, a total electron
temperature increase (with a parallel temperature decrease but a perpendicular
temperature increase), and strong currents carried by the electrons. The
current has a dip in the center of the magnetic hole and a peak in the outer
region of the magnetic hole. The estimated size of the magnetic hole is about
0.23 \r{ho}i (~ 30 \r{ho}e) in the circular cross-section perpendicular to its
axis, where \r{ho}i and \r{ho}e are respectively the proton and electron
gyroradius. There are no clear enhancement seen in high energy electron fluxes,
but an enhancement in the perpendicular electron fluxes at ~ 90{\deg} pitch
angles inside the magnetic hole is seen, implying that the electron are trapped
within it. The variations of the electron velocity components Vem and Ven
suggest that an electron vortex is formed by trapping electrons inside the
magnetic hole in the circular cross-section (in the M-N plane). These
observations demonstrate the existence of a new type of coherent structures
behaving as an electron vortex magnetic hole in turbulent space plasmas as
predicted by recent kinetic simulations.
