Rocket measurements of the geomagnetic field above Woomera, south Australia

Abstract

Two B r i t i s h S k y l a r k r e s e a r c h r o c k e t s , e a c h c a r r y i n g a p r o t o n magnetometer, were flown from t h e Woomera Rocket Range, South A u s t r a l i a , i n March 1964. i , 'The f i r s t f l i g h t merely recorded an a p p r o x i m a t e l y i n v e r s e jcube J l a w v a r i a t i o n of magnetic f i e l d w i t h h e i g h t b u t on t h e second f l i g h t a magnetic d i s c o n t i n u i t y , of approximately24 gammas a m p l i t u d e , was r e c o r d e d . T h e s e r e s u l t s 4 r e c o n s i s t e n t w i t h ground o b s e r v a t i o n s at 3t h e times of t h e two f l i g h t s and they e s t a b l i s h e x p e r i m e n t a l l y t h e I I e x i s t e n c e of an electric c u r r e n t system i n t h e E-region of t h e 1 i o n o s p h e r e o v e r Sopth A u s t r e l i a .of t h e c u r r e n t are, however, n o t in c l o s e agreement w i t h t h e o r e t i c a lThe h e i g h t and v e r t i c a l t h i c k n e s s p r e d i c t i o n s .

Rocket measurement ofSqionospheric currents over Kagoshima, Japan

“…Because the magnetic field changes are much smaller than those at or near the geomagnetic equator, their dete•tion involves many experimental difficulties. The first successful measurement was made by Burrows and Hall [1965] In this brief report we report on the results of rocket measurement of the mid-latitude Sq currefits. The magnetic sensor used was a self-oscillating scalar magnetometer with cesium vapor.…”

A Note on the Height of the Geomagnetic Sq Current

“…This result which only slightly changes if one adopts other reasonable vertical wind profiles seems to be inconsistent with rocket born measurements of the Sq current by Dads et al (1965) and Burrows and Hall (1965). Both groups deduced from their observations an electric current sheet of about 10 to 20 km thickness near 110 to 115 km altitude which they associated with the Sq current.…”

Mid-latitude winds and electric fields in the lower thermosphere and their relationship with the global Sq ionospheric current system.

“…Subsequently, the rate of progress has become more rapid, global models of the Sq equivalent current system being used by MAEDA (1955) and KATO (1956) to deduce the nature of the global, diurnal wind pattern responsible for the currents-via the dynamo mechanism. That winds of comparable magnitude existed in the dynamo region was verified by direct measurement using chemical releases between 1958 and 1960 and, subsequent to refinements of the dynamo theory (BAKER and MARTYN, 1953;FEJER, 1965;BURROWS andHALL, 1965 andDAVIES et al, 1966), provided the first 268 D. BEES direct evidence from a rocket-borne magnetometer for the actual existence of the Sq current layer.…”

“…Despite the direct corroboration of the current layer's existence (BURROWS and HALL, 1965), it has proved to be very difficult to measure simultaneously all the necessary atmospheric and ionospheric parameters needed to demonstrate that a rather simple concept-Ohm's Law-does, in fact, hold true for the ionospheric current system.…”