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New types of magnetospheric electric field emissions have been detected by Ogo 5 with wave frequencies (f) above the local electron cyclotron frequency (fc). The most common emissions occur between the lowest electron cyclotron harmonics (f ≈ 3fc/2), followed by emissions at high frequencies (f≫fc). A few signals have been observed slightly above the local fc. The strong emissions with f≳3fc/2 appear to be localized within a few degrees of the geomagnetic equator. More than 60% of the equator crossings between 4

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While in the lobes of the distant magnetotail, ISEE‐3 encountered regions of compressed magnetic field, δB/Bo=0.3‐0.1, at a rate of several per day. The duration of these events was 5 to 20 minutes and they were observed 10 to 30 minutes following the onset of substorm activity near the earth. During each event, the lobe magnetic field tilted first northward and then southward with the inflection point near the time of peak field strength. Following the compression events, the lobe field weakened and retained a southward component for 20 to 40 minutes. It is suggested that these traveling compression regions (TCR’s) are the lobe signatures of plasmoids moving rapidly down the tail in the plasma sheet. Comparison of ISEE‐3 compression event times with substorm onset times yielded propagation speeds of 350 to 750 km/s.