Solar and Stellar Physics Group

Welcome to the Solar and Stellar Physics Group, which is part of NYU Abu Dhabi's Center for Space Science. The group is interested in the internal structure and outer atmospheres of the Sun and Stars. The main research fields include:

Convection
Magnetism and Space Weather
Astrophysical Waves

The cores of the Sun and stars generate a lot of heat, due to nuclear fusion. This heat must be transported to the surface of the star. Depending on the composition and mass of the star, this can occur through convection; a process by which hot material rises against gravity and cold material sinks. In the Sun it is thought that the outer 30% of the Sun is convective.

The physics present in the Sun is very difficult to replicate in laboratories or numerical simulations. Thus, we still do not fully comprehend the convective structures and physics within the Sun and stars. Here, we strive to better understand the unique convective physics present in the interior of stars through the techniques of helio- or asteroseismology.

The sun and stars generate lots of energy in their core through fusion. This heat must escape and in the Sun this heat loss occurs through convection in the outer 30% of the interior. Convection is where hot material rises to the surface, cools and sinks again to be heated in the interior.
The Sun and stars are magnetically active. We know that our Sun has an 11 year magnetic cycle, within which it goes from a period of low surface magnetic activity to high magnetic activity (sun spots, flares etc.), and then returns to low activity. Our group has also found other stars with magnetic cycles. The Sun's magnetic cycle is important to our life on Earth, since magnetic activity drives space weather and can have profound impact on our modern technology. Our goal is to further understand the physics and structures related to solar and stellar magnetism.

Solar flare---seen as a bright flash in the middle of the Sun---which occurred on May 10, 2022. Captured by NASA's SDO spacecraft.
Stars are host to all kinds of waves; including sound waves, inertial waves and gravity waves. While we cannot see the interior of the Sun and stars using conventional tools of astronomy, we can understand stellar structures and life cycles by analyzing the waves that occur within them. These waves appear as oscillations on the surface of the Sun or stars. By characterizing these waves (e.g. their frequencies and amplitudes) we can better understand our own Sun and the stars in our galaxy.

Artist impression of the high-frequency retrograde vorticity waves discovered in the Sun by the CSS Solar and Stellar Physics Group. Image by Mark Garlick

Group Members

Collaborators: Martin Woodard, Jeroen Tromp, Srijan Das, Prasad Mani, Max Planck Institute for Solar System Research,TIFR Seismology Group

https://nyuad.nyu.edu/en/news/latest-news/science-and-technology/2016/november/sizing-up-a-distant-star-with-astonishing-precision.html — "The roundest natural object ever measured". Using the technique of asteroseismology, we have measured, with amazing precision, the oblateness of Kepler 11145123. We found that this star is the roundest natural object ever measured.

Opportunities

Students and researchers interested in working with the Solar and Stellar Physics Group should contact nyuad.spacescience@nyu.edu for more information.