NEW DELHI: Nasa’s Nancy Grace Roman Space Telescope is poised to revolutionize our understanding of the Milky Way by accurately determining the ages of stars. Launching by May 2027, this advanced space telescope will measure the rotation periods of hundreds of thousands of stars, leveraging the principle that stars slow down as they age due to magnetic braking.This phenomenon, caused by the interaction between the stellar wind and the star’s magnetic field, results in a loss of angular momentum and a reduction in spin speed.
Understanding a star’s rotation rate is key to estimating its age. This is because, after about a billion years, stars of the same mass and age tend to spin at similar rates. The Roman Space Telescope’s ability to measure these rotation periods will thus provide invaluable insights into the evolutionary history of our galaxy.
Astronomers currently rely on changes in a star’s brightness caused by starspots to gauge its rotation rate. However, this method is complicated by the dynamic nature of starspots. To overcome these challenges, a team of astronomers at the University of Florida is employing artificial intelligence, specifically a convolutional neural network, to analyze light curves representing a star’s brightness over time. This approach has already shown promise in accurately measuring longer stellar rotation periods using data from Nasa’s TESS (Transiting Exoplanet Survey Satellite).
The Roman Space Telescope’s Galactic Bulge Time Domain Survey will observe the center of our galaxy, a densely populated star field, to study brightness variations over time. This survey, alongside other core community surveys, will not only aid in the search for exoplanets but also enhance our understanding of stellar dynamics. The survey design, still under development by the astronomical community, will benefit from the Nasa-funded study on stellar rotation, ensuring optimal data collection strategies are in place when the telescope becomes operational.
Managed at Nasa’s Goddard Space Flight Center, with contributions from multiple institutions and industrial partners, the Roman Space Telescope represents a significant leap forward in space science and our quest to understand the cosmos.
What are the core community surveys of the Roman Space Telescope?
The Nancy Grace Roman Space Telescope will conduct three core community surveys, which are central to its mission of advancing our understanding of the universe. These surveys are designed to address a broad range of scientific questions, from the mysteries of dark energy and exoplanet exploration to the structure and evolution of the universe. While the specific surveys of the Roman Space Telescope may evolve as the mission’s design is finalized, they are aimed at leveraging the telescope’s advanced capabilities for wide-field infrared imaging and spectroscopy. Here’s an overview of the types of core community surveys the Roman Space Telescope might undertake:
Dark Energy Surveys: These surveys are intended to investigate the nature of dark energy by mapping the distribution of galaxies and galaxy clusters over vast volumes of the universe. By measuring how the distribution of these objects has changed over cosmic time, scientists hope to understand how dark energy has influenced the expansion of the universe.
Exoplanet Surveys: Roman will conduct surveys designed to discover and characterize exoplanets using the microlensing technique. This method relies on the gravitational bending of light from a background star by a foreground object to magnify and reveal planets around stars in our galaxy, providing insights into the demographics of planetary systems.
Infrared Surveys of the Cosmic Infrared Background: By observing the sky in infrared light, Roman will be able to study the cosmic infrared background, which is composed of the collective light from all galaxies that have ever existed. These surveys will help scientists understand the formation and evolution of galaxies across cosmic history.