  A hot flow anomaly (HFA) like event was observed by the Solar TErrestrial
RElations Observatory (STEREO) in the night side magnetosheath in the far tail
in February-March 2007. The magnetic signature of the tangential discontinuity
was visible, but the resolution of the plasma ion data is not sufficient for
our analysis, so a method is given to identify HFAs without solar wind velocity
measurements. The event observed in the night side magnetosheath in the far
tail might be the remnant of an HFA event, a not-so-active current sheet. This
observation suggests that the lifetime of the HFAs might be several 10 minutes,
much longer than the expected several minutes.
