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Several important problems in solar radio physics can be attacked using the high spatial resolution observations from a low frequency space array, as the problem of ionospheric refraction does not exist. Noise storms are believed to occur in closed magnetic loops due to trapped superthermal particles. Recent radioheliograph observations suggest such a magnetic field topology up to altitudes of about 40 MHz emission. The problem of relative locations and sources of the storm continuum and bursts can be effectively studied by imaging them with higher spatial resolution. Interplanetary type II bursts are observed from heights above ~ 10 R⊙ while coronal type II bursts are observed from heights less than ~ 3 R⊙. Observations filling this gap have important implications for the understanding of solar-terrestrial relations through shocks and mass ejections.

We review some recent results obtained from 2-dimensional imaging observations of the Sun using the Clark Lake multifrequency radioheliograph. The radioheliograph produced images of the Sun's corona on a daily basis at several frequencies within the range 20–125 MHz during the period 1982–87. Using these images both large scale structures as well as transient phenomena such as bursts have been studied. In this paper we discuss the nature of radio emission associated with eruptive filaments and CMEs. It is possible to trace the structure of magnetic fields in the corona based on the multifrequency observations of moving type IV bursts at meter and decameter wavelengths. We illustrate this by discussing specific events. We discuss a rare case of the detection of thermal radio emission in association with a fast CME. We estimate the CME mass using spatially resolved radio data.

A study of meter-dekameter radio emission associated with the 1986 Feb 10 coronal Mass ejection event is presented here. The event was accompanied by a major flare (optical importance 1B and X-ray importance C9.6), preceded by a filament disappearance. Changes in the intensity of a pre-existing noise storm was observed during the onset of the flare. A flare continuum, a moving type IV, and a type II occurred during the event. The event was also associated with a strong hard X-ray burst. The speeds of moving type IV burst and CME were of the same order of 1600 kms−1, while the type II shock speed was 1900 kms−1. The positional data indicate that the moving type IV burst and the inferred type II shock had different trajectories. The moving type IV burst was confined to one leg of the CME while the type II shock was far ahead of the CME leading edge. We discuss the inferred relation among different entities such as the CME, type II shock, type IV plasmoid and the erupting filament.

UV Ceti: This system is a visual binary L726-8AB with separation of about 2". The observations of 21:48 to 22:54UT on February 6 resolved both components at both 20em and 6cm. Observations of 5min. duration were made alternately at the two wavelengths. The flux density of UVCet (L726-SB) was observed to increase from 1.7 to 3.2mJy, and finally to about =10mJy rather impulsively. Fig. i shows the time variation of UVCet's flux at 20cm. At 6cm the flux of UVCet was essentially constant at =2.5mJy. The primary star L726-SA was observed only during the first two 5mln. intervals; it was below the limit of detection from the third interval through the impulsive rise phase. At 6em the primary star shows only weakly on the time averaged map at a level of 0.34mJy.

We present simultaneous microwave and X-ray data for two microwave bursts with simple impulsive time profiles. The 17 GHz images show compact sources, and in the one case for which we have simultaneous soft and hard X-ray images, they also show compact sources coincident with the radio source. One of the bursts is barely detected in soft X-rays, yet has a moderate 17 GHz flux,.