Why do we need a large solar telescope?

The Sun is a unique astrophysical observatory that has revealed fundamental information which hasprofound impact on physics. The complexities of the Sun involving its internal structure, rotation, convection, magnetic fields, activity and explosive processes in its outer atmosphere are areas of major research which have important astrophysical applications in stars, accretion disks and galaxies. Furthermore, solar physics today has a growing relevance to climate research and space weather in the Earth's environment. Studies of the Sun have contributed to the development of several fields of physics through an understanding of phenomena that involve scales that cannot be simulated in laboratories on the Earth. The Sun has provided tests of the general theory of relativity and studies of its interior have contributed in a significant way to neutrino physics.

Being the nearest star, observations of the Sun reveal details one can never hope to see in distant stars. Precisely because of the richness of the data, it has been a major challenge to understand the complexities of the Sun.

NLST Main Science Goals

NLST's innovative design and backend instruments will enable observations with an unprecedented high spatial resolution that will provide crucial information on the nature of magnetic fields in the solar atmosphere. The following broad science areas will be actively pursued:

  • Magnetic field generation and Solar Cycle: With its high spatial, spectral and temporal resolution, NLST will enable observations that will provide constraint on dynamo models and improve the prediction of the sunspot cycle;
  • Dynamics of magnetized regions: Understanding the nature associated with magnetic fields is crucial for unravelling the processes that heat the solar chromosphere and corona.
  • Helioseismology: This is a powerful technique for probing the solar interior using sound waves. This involves coverage of full sun and continuous observations over a long period. On the other hand the waves confined to limited active regions may show the effect of local dynamos. Velocity and magnetic information over a few minutes of arc will be needed
  • Long term variability: Solar activity cycle and irradiance variability over the cycle are well known. Synoptic observations combined with carefully selected high resolution observations of a few representative regions on the Sun will be used to investigate this phenomenon
  • Energetic phenomena: High-resolution and high-cadence vector magnetograms are crucial information to study the dynamic changes associated with flares. Other energetic processes that will be studied are Coronal Mass Ejections (CMEs) and Prominences.