NASA’s Roman Space Telescope could reveal dark energy’s deepest secrets

image via New Scientist

August 26, 2026, 1:45 PM

• •The article says NASA plans to launch the Nancy Grace Roman Space Telescope as soon as August 30, with full operations expected early next year.
• •Roman is designed to study dark energy using three methods: supernova distance measurements, large-scale galaxy mapping, and microlensing-based studies of matter distribution.
• •The story highlights growing tensions in cosmology, including the Hubble tension, sigma-eight tension, and DES/DESI hints that dark energy may change over time.
• •Roman will complement ESA's Euclid telescope and the Vera C. Rubin Observatory, with overlapping surveys meant to reduce observational bias.
• •Scientists quoted in the piece say the new data may not fully explain dark energy but should test whether it evolves over cosmic time.

NASA’s Nancy Grace Roman Space Telescope is about to join a major new push to investigate dark energy, the poorly understood force driving the universe’s accelerating expansion. The article says recent tensions in cosmological measurements, including results from DES and DESI, have raised the possibility that dark energy may evolve over time instead of behaving like a simple cosmological constant. Roman will probe the issue through supernova observations, large-scale galaxy mapping and microlensing studies of matter distribution. Together with Euclid and the Vera C. Rubin Observatory, it is expected to provide sharper evidence that could either reinforce or revise the standard model of cosmology.

Read original article