NASA’s Nancy Grace Roman Space Telescope is set to launch no later than May 2027 and will be equipped with a powerful wide field instrument that can capture an area 200 times larger than the Hubble Space Telescope’s infrared camera. The telescope’s near-infrared Wide Field Instrument will enable scientists to conduct three core community surveys, one of which focuses on detecting tens of thousands of type Ia supernovae.
The High-Latitude Time-Domain Survey, part of these core surveys, aims to detect supernovae that can be used to study the expansion history of the universe. By measuring the distance and speed of these events, scientists can gain insights into dark energy and its role in the universe’s evolution.
Roman will complement existing telescopes like the Vera C. Rubin Observatory, which are limited by atmospheric absorption, and will detect fainter supernovae that illuminate early cosmic epochs. This will expand the measured timeline of the universe’s expansion history, potentially allowing scientists to test recent findings that dark energy may be weakening over time.
To detect transient objects, Roman will revisit the same fields at regular intervals using a technique called image subtraction. The survey will also include an extended component that will collect data on rare and distant events, such as tidal disruption events and pair-instability supernovae.
The High-Latitude Time-Domain Survey is part of a multi-survey program aimed at mapping the universe with unprecedented clarity and depth. With its advanced capabilities, Roman is poised to make groundbreaking discoveries about dark energy, the expansion history of the universe, and the nature of transient events.
Source: https://www.nasa.gov/missions/roman-space-telescope/nasa-roman-core-survey-will-trace-cosmic-expansion-over-time