Scientists conduct experiments to study sun during eclipse

Scientists travelled far and wide to avail of the unique opportunity to conduct experiments and study the sun during the longest total solar eclipse of the 21st century -- described as a once-in-a-life time event.

As the eclipse began, astronomers -- amateur and professional alike -- aimed their telescopes to the sky to capture every moment of the moon's shadow covering the sundial.

Many of them had gathered at Taregna in Bihar, the best site in the world to watch the celestial spectacle, while others perched on hilltops in Katni in Madhya Pradesh and took theur places along the famed ghats of river Ganga in Varanasi.

"We conducted the experiment to study the sun's corona. No filters were used but high quality tele-lens were used to study the phenomenon," said RC Kapoor, a scientist with the Bangalore-based Indian Institute of Astrophysics (IIA).

Kapoor along with other colleagues from IIA had made Varanasi, where the sun remained covered for three minutes and 10 seconds, as their base to study the eclipse.

"Observations of the solar corona, a hot atmosphere of ionized gas around the Sun visible only during the totality in solar eclipses, are very important in order to understand the complex processes that heat it up to two million degrees Celsius while the Sun's surface temperature is at about 5,700 degrees Celsius, Kapoor said.

A team of scientists from IIA and professional astronomers travelled to Anji in eastern China, where the period of totality was five minutes 38 seconds, to carry out  experiments during the eclipse.

Siraj Hasan, director IIA led a team of six scientists which was looking for existence of waves in the solar corona, their nature and the reasons for higher temperature in the sun's outer layer than its surface.

An observation camp was set up in Anji where they mounted a 30 cm two mirror system to direct the sunlight and the coronal light onto the slit of a Littrow type spectrograph.

The scientists conducted photometry of the corona using two 40 cm telescopes in the red emission line (FeX) and the green line (FeXIV) of multiple ionized iron through filters centered around 637.4 nm and 530.3 nm respectively.

In China another NGO Science Popularisation Association of Communicators and Educators (SPACE) conducted scientific experiments relating to temperature and light variation besides wind speed variations.

"We were able to see the diamond ring formation when solar eclipse was in its totality which it inturn provided us an opportunity to do our experiments," CB Devgun, director SPACE said.