Breakthrough: IIA Bengaluru uses dish TV antenna to study Sun
BENGALURU: It is possible to measure the Sun's magnetic field using commercial dish TV antennas. In a major breakthrough to study the Sun, the radio astronomy group at the Indian Institute of Astrophysics (IIA), Bengaluru has proved that low-cost dish antennas that are used for TV networks can be used to observe the Sun and its magnetic field.
'The scientific and technical personnel at IIA, associated with the Gauribidanur radio astronomy field station near Bengaluru, are successfully operating a unique and large world-class radio antenna array for regular observations of the solar corona and magnetic field.
The observations are carried out every day unlike the optical observations, where the solar corona can be observed from the ground only during a total solar eclipse. The radio observations are not affected by the clouds,' said Prof R Ramesh, senior professor at IIA.
He is in charge of the institute's radio astronomy field station at Gauribidanur and is the principal investigator for the VELC instrument on board Aditya-L1, India's maiden space mission for dedicated observations of the Sun.
'The solar corona overlying the Sun's photosphere as well as present beyond its limb can be observed with a radio telescope. These are unique advantages of radio observations. The antennas used in the array are designed and fabricated in the Gauribidanur observatory workshop. The analog and digital receiver systems are also developed in-house using off-the-shelf components,' he added.
While the measurement of the Sun's magnetic field at its visible surface (the photosphere) is routinely carried out with both ground and space-based observational facilities, regular measurements of the extension of the same magnetic field to the outer layers in the Sun's atmosphere like the chromosphere and corona are not there.
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BENGALURU: It is possible to measure the Sun's magnetic field using commercial dish TV antennas. In a major breakthrough to study the Sun, the radio astronomy group at the Indian Institute of Astrophysics (IIA), Bengaluru has proved that low-cost dish antennas that are used for TV networks can be used to observe the Sun and its magnetic field. 'The scientific and technical personnel at IIA, associated with the Gauribidanur radio astronomy field station near Bengaluru, are successfully operating a unique and large world-class radio antenna array for regular observations of the solar corona and magnetic field. The observations are carried out every day unlike the optical observations, where the solar corona can be observed from the ground only during a total solar eclipse. The radio observations are not affected by the clouds,' said Prof R Ramesh, senior professor at IIA. He is in charge of the institute's radio astronomy field station at Gauribidanur and is the principal investigator for the VELC instrument on board Aditya-L1, India's maiden space mission for dedicated observations of the Sun. 'The solar corona overlying the Sun's photosphere as well as present beyond its limb can be observed with a radio telescope. These are unique advantages of radio observations. The antennas used in the array are designed and fabricated in the Gauribidanur observatory workshop. The analog and digital receiver systems are also developed in-house using off-the-shelf components,' he added. While the measurement of the Sun's magnetic field at its visible surface (the photosphere) is routinely carried out with both ground and space-based observational facilities, regular measurements of the extension of the same magnetic field to the outer layers in the Sun's atmosphere like the chromosphere and corona are not there.
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