We discuss some implications of the finite lifetime of a short-lived near-equatorial coronal hole for the structure of a corresponding transitory corotating stream and magnetic field in the heliosphere. The discussion is based on the illustrative example of a corotating stream that was observed by the Wind spacecraft in the ecliptic at 1 AU in early 1998 and the associated solar observations. The transitory corotating stream was associated with a near-equatorial coronal hole that formed, persisted for at least two solar rotations, and disappeared, all in response to the magnetic flux in evolving active regions. The corotating stream recurred for two solar rotations, and its emission time, based on the coronal hole observations, was approximate to 66 +/- 6 days. The intersection of the resulting corotating stream with the ecliptic plane has the form of a spiral-shaped object with a radial extent on the order of 19 +/- 2 AU. The magnetic field configurations in transitory corotating streams are not known. One possibility is that the transitory corotating stream originates from a localized near-equatorial coronal hole, possibly a member of a pair of coronal holes, joined by a flux tube, which evolve together. Such a transitory corotating stream could carry the flux tube through the corona and heliosphere. Another possibility is that the transitory corotating stream is the result of the latitudinal motion and deformation of the boundary of a polar coronal hole and the associated redistribution of a constant amount of open magnetic flux. Models and further observations of transitory corotating streams and their magnetic fields are needed in order to better understand them. [References: 41]
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