Scheduled for launch in May 2027, NASA’s Nancy Grace Roman Space Telescope promises to revolutionize our understanding of the universe. With a field of view 100 times larger than the Hubble Space Telescope, Roman will explore the cosmos faster and with greater precision.
The mission aims to study billions of cosmic objects, shedding light on the formation of planets, stars, and galaxies, while helping scientists address key mysteries such as the accelerating expansion of the universe.
ROMAN’S REVOLUTIONARY FIELD OF VIEW
The Roman Space Telescope will conduct large-scale sky surveys with unprecedented speed. Its wide field of view allows it to scan the sky 1,000 times faster than Hubble while maintaining similar sensitivity. This innovation will provide a comprehensive view of the universe, essential for addressing critical scientific questions.
One of Roman’s primary objectives is to investigate dark energy, the mysterious force responsible for the universe’s accelerated expansion. Dark energy accounts for 68% of the universe’s content, yet its nature remains unknown. Roman will explore whether this acceleration is due to dark energy or signals a breakdown of Einstein’s general theory of relativity.
WIDE FIELD INSTRUMENT: UNVEILING COSMIC MYSTERIES
Roman’s powerful Wide Field Instrument and 2.4-meter mirror will play a pivotal role in exploring dark energy. By mapping the structure and distribution of matter across the universe, Roman will help astronomers measure how the universe has expanded over time.
Roman’s surveys will examine galaxies dating back to when the universe was only 4% of its current age—about half a billion years old. By studying galaxies throughout cosmic time, Roman will provide insights into how they formed and evolved.
The mission will use a variety of observational methods, including surveys of supernovae and galaxy clusters. Measuring the brightness and distances of supernovae first revealed the existence of dark energy. Roman will extend these studies, focusing on greater distances to track how dark energy has influenced the universe over time.
Roman will measure precise distances to galaxy clusters, mapping their growth over billions of years. It will also determine the redshift of millions of galaxies—a key phenomenon where light becomes redder as galaxies move farther away. This 3D mapping will help scientists understand how dark energy has shaped the cosmos.
WEAK GRAVITATIONAL LENSING: MEASURING MATTER IN THE UNIVERSE
Einstein’s theory of relativity predicts that massive objects, like galaxies, curve space-time. This curvature bends light, creating a magnified and distorted view of distant galaxies. Roman will use this weak gravitational lensing effect to measure the matter in hundreds of millions of galaxies.
By studying how matter is structured throughout the universe, Roman will put the governing physics of cosmic assembly to the ultimate test. These measurements will provide insights into the nature of dark matter and dark energy, crucial for understanding the forces shaping our universe.
MICROLENSING: DISCOVERING EXOPLANETS
In addition to its cosmic survey, the Roman Space Telescope will use microlensing to detect exoplanets. Microlensing occurs when a foreground star aligns with a distant background star, magnifying the background star’s light. As the alignment shifts, the brightness of the star changes, revealing planets orbiting the foreground star.
Roman’s microlensing survey will monitor 100 million stars over hundreds of days, likely detecting around 2,500 exoplanets. This method will identify planets smaller than Mars, as well as those at varying distances from their host stars—ranging from close to Venus to beyond Pluto. Roman’s findings will complement other missions like the Transiting Exoplanet Survey Satellite (TESS), providing a more complete picture of exoplanet populations.
Together with missions like TESS, Roman will help scientists understand how planets form and migrate within their solar systems. Its ability to detect rocky planets in regions where liquid water might exist makes it essential for studying potentially habitable worlds.
CORONAGRAPH INSTRUMENT: DIRECTLY IMAGING EXOPLANETS
Roman’s Coronagraph Instrument will demonstrate new technologies designed to directly image exoplanets. By blocking the light from a host star, the coronagraph will allow astronomers to observe much fainter planets in orbit around it.
This instrument will showcase advanced techniques that could be used in future missions to directly image Earth-like exoplanets. By observing these distant worlds, scientists hope to better understand planetary atmospheres and the potential for life beyond our solar system.
ROMAN’S GENERAL INVESTIGATOR PROGRAM
In addition to its primary mission, Roman will serve the global scientific community. Through the General Investigator program, scientists can submit proposals to use the observatory for their own research. All data collected by Roman will be made publicly available immediately after processing.
This open data policy ensures that researchers around the world can use Roman’s findings to explore a wide range of scientific questions. From studying nearby exoplanets to mapping distant galaxies, the Roman Space Telescope will be a key tool for astronomers for years to come.
