quiet Sun

solar images

Technical Readiness of MeerKAT for Solar Observations and Initial Science Results by D. Kansabanik et al.

March 31, 2026

Solar radio emissions offer unique diagnostic insights into the solar corona. However, their dynamic and multiscale nature, along with variations spanning several orders of magnitude in intensity, pose significant observational challenges. To date, at gigahertz frequencies, MeerKAT (Jonas & MeerKAT Team 2016) stands out globally for its intrinsic ability to produce high-fidelity, spectroscopic snapshot images of the Sun. This is enabled primarily by its dense core, high sensitivity, and broad […]

Spectroscopic Imaging of the Sun with MeerKAT: Opening a New Frontier in Solar Physics by Kansabanik et al.

April 10, 2024

Since the discovery of solar radio emission in the late 1940s, the Sun has been studied in great detail across a wide range of frequencies from a few tens of kHz to several hundreds of GHz. Solar radio emissions provide several unique diagnostics of the solar corona, which are otherwise simply inaccessible. Despite this long history of observations and studies, the Sun still harbors several mysteries. Improved observations from the […]

Radio Interferometric Observations of the Sun Using Commercial Dish TV Antennas by G. V. S. Gireesh et al.*

November 9, 2021

Commercial dish TV antennas are parabolic structures designed to receive radio waves from a communication satellite. The antennas and the associated front end receiver systems have improved with advances in the TV systems. They operate typically over the frequency range 10.7 – 11.7 GHz (Ku-band) and provide very good signal-to-noise ratio (SNR). It is well known that the Sun emits intense radio emission in the above frequency range with brightness […]

Radio, X-ray and extreme-ultraviolet observations of weak energy releases in the ‘quiet’ Sun by Ramesh et. al.

October 26, 2021

Small scale energy releases on the Sun e.g., flaring bright points, active region transient brightenings, etc. have been studied using X-ray and radio observations. The observations of low frequency radio type III bursts in associated with X-ray bright point flares (Kundu et. al. 1980) and coronal X-ray jets (Aurass et. al. 1994) indicated that the latter are capable of accelerating particles to non-thermal energies, as well as producing the heated […]

Propagation Effects in Quiet Sun Observations at Meter Wavelengths by R. Sharma and D. Oberoi

February 2, 2021

The quiet Sun coronal emission dominantly comes from thermal bremsstrahlung. As this radiation traverses the coronal medium on its way to the Earthbound observer, the coronal optical depth, τ, along typical ray paths is neither low enough to be approximated as optically thin, nor high enough to be treated as optically thick. On its way to the observer, it gets modified substantially due to propagation effects —primarily refraction and scattering—through the […]