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Measurements of the hydrogen auroral emissions have been made by rocket‐borne photometers simultaneously with observations of the energy spectra and pitch angle distributions of the precipitating energetic particles. The rocket was flown through a postbreakup auroral glow known to be associated with proton precipitation on the basis of optical measurements from the ground. The observed Hβ profiles are compared with the profiles derived from the measured primary proton beam and obtained by using Eather's (1967) values for the pertinent excitation cross sections. Good agreement between measured and computed profiles is obtained. The measured height profiles had the same shape during the ascent and descent parts of the flight, although the intensity of the Hβ emission varied by a factor of 2. The maximum volume emission rate was found to be at 112±1 km in both cases, whereas the half value emission rates were at 107 and 119 km. The atmospheric density above 120‐km altitude had to be reduced by a factor of 2 in comparison with the Cira (1965) model atmosphere in order to account for the observed energy degradation of the incoming proton beam.

The HEating ROcket project HERO comprised the first in situ experiments to measure artificial ionospheric modifications at F layer heights set up by radio waves transmitted from the Heating facility at Ramfjord near Tromso in Northern Norway. Four instrumented payloads were launched on sounding rockets from Andoya Rocket Range during the autumn of 1982 into a sunlit ionosphere with the sun close to the horizon. The payloads recorded modifications, in particular, the presence of electron plasma waves near the reflection level of the heating wave. The amplitude and phase of the three components of the electric and magnetic fields of the heating wave were measured simultaneously as a function of altitude. Coherent spectra of the three electric field components of the locally generated electron plasma waves were obtained in a 50-kHz-wide band. At the same time quasi-continuous measurements were made on several fixed frequencies from 4 kHz to 16 kHz below the heating frequency and in the VLF-range using linear dipole antennas. Moreover, measurements were made of electron temperature, suprathermal electrons and local electron density along the rocket trajectory. The experimental results will be presented and discussed.

Abstract. The PULSAUR II rocket was launched from Andùya Rocket Range at 23.43 UT on 9 February 1994 into a pulsating aurora. In this paper we focus on the observations of precipitating electrons and auroral X-rays. By using models it is possible to deduce the electron energy spectrum from X-ray measurements. Comparisons are made between the deduced electron uxes and the directly measured electron¯uxes on the rocket. We found the shape of the observed and the deduced electron spectra to ®t very well, with almost identical e-folding energies in the energy range from 10 ke V to $ 60±80 ke V. For the integrated¯uxes from 10.8 to 250 ke V, we found a discrepancy of 30% . By combining two models, we have found a good method of deducing the electron precipitation from X-ray measurements. The discrepancies between calculations and measurements are in the range of the uncertainties in the measurements.

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