Level 1 — Absolute Beginner

NASA has announced that a new space telescope called the Roman Space Telescope will launch on August 30, 2026. It will travel to space on a rocket called the Falcon Heavy, made by SpaceX. The launch is happening much sooner than scientists first planned.

The Roman telescope has a very powerful camera. This camera can take pictures of very large parts of the sky at once. The pictures show light that human eyes cannot see, called infrared light.

The telescope will travel very far from Earth, about 1.5 million kilometres away. It will orbit a special point in space where gravity from the Earth and the Sun balance out. This point is called L2.

Scientists hope Roman will help answer big questions. What is the invisible force that makes the universe expand faster and faster? Are there planets far away from their stars, floating freely in space? Roman will help us find out.

telescope

a tool used by scientists to see objects in space that are very far away

launch

to send a rocket or spacecraft into space

infrared

a type of light that humans cannot see with their eyes but that cameras and telescopes can detect

orbit

to travel in a circular or oval path around a planet, moon, or other object in space

gravity

the force that pulls objects toward each other; it keeps planets orbiting the Sun and the Moon orbiting Earth

universe

everything that exists, including all stars, planets, galaxies, and space itself

expand

to grow larger or spread out

planet

a large round object in space that orbits a star

Level 2 — Elementary

NASA confirmed that the Nancy Grace Roman Space Telescope will launch on August 30, 2026, almost eight months ahead of its originally planned readiness date in May 2027. The spacecraft will launch on a SpaceX Falcon Heavy rocket from Launch Complex 39A at Kennedy Space Center in Florida, the same pad used by NASA's Artemis moon missions.

Roman carries a 300-megapixel infrared wide-field camera that can photograph a patch of sky 100 times larger than Hubble's main camera can, while producing images of similar sharpness. This means Roman can survey large areas of the sky quickly. It will orbit at the Sun-Earth L2 Lagrange point, approximately 1.5 million kilometres from Earth, where it will have a clear view of deep space without Earth blocking sunlight.

The telescope has three main scientific goals. First, it will study dark energy, the mysterious force causing the universe to expand at an accelerating rate. Second, it will search for exoplanets using a technique called microlensing, which detects planets when they pass in front of distant stars and briefly brighten them. Third, it will test a coronagraph instrument designed to block a star's light so that nearby planets become visible.

Roman is named after Nancy Grace Roman, NASA's first Chief of Astronomy, who served from 1959 to 1979. Roman played a key role in the planning that eventually led to the Hubble Space Telescope. The new telescope that bears her name is expected to transform our understanding of the cosmos over its planned five-year mission.

megapixel

one million pixels; a measure of the resolution of a digital camera or image

wide-field camera

a camera that can photograph a large area of the sky in a single image

Lagrange point

one of five positions in space where the gravitational forces of two large bodies and a small object's orbital motion balance, allowing the object to orbit stably

dark energy

a mysterious form of energy thought to be causing the universe to expand at an accelerating rate

exoplanet

a planet that orbits a star outside our solar system

microlensing

a technique for detecting distant planets by observing how their gravity bends and brightens the light of a star behind them

coronagraph

an instrument that blocks the bright light of a star so that fainter objects near it can be observed

accelerating

speeding up; increasing in rate or pace

Level 3 — Intermediate

NASA officially confirmed an August 30, 2026 launch date for the Nancy Grace Roman Space Telescope, nearly eight months ahead of the previously projected May 2027 readiness schedule. The spacecraft will lift off on a SpaceX Falcon Heavy from Kennedy Space Center's Launch Complex 39A and transit to the Sun-Earth L2 Lagrange point, approximately 1.5 million kilometres from Earth, where the James Webb Space Telescope also orbits. The early launch date reflects completion of hardware integration and environmental testing ahead of schedule, and was formally announced following a successful launch readiness review.

Roman's primary instrument is a 300-megapixel wide-field infrared sensor array (WFI) covering a field of view of 0.281 square degrees, approximately 100 times the area of Hubble's Wide Field Camera 3 at comparable angular resolution. The WFI operates across six photometric bands spanning 0.48 to 2.3 micrometres. This combination of wide area and high resolution will allow Roman to survey billions of galaxies, measure cosmic shear from weak gravitational lensing, and map baryon acoustic oscillations (BAO), both of which are sensitive probes of the dark energy equation-of-state parameter w.

Roman's second science pillar is a statistical exoplanet census using gravitational microlensing. By monitoring hundreds of millions of stars toward the galactic bulge at high cadence, Roman is expected to detect between 1,400 and 2,500 bound exoplanets via microlensing events, with particular sensitivity to planets at orbital separations of 1 to 10 astronomical units, a region poorly sampled by the Kepler and TESS transit missions. In addition, Roman's microlensing survey is uniquely sensitive to free-floating planets that have been ejected from their stellar systems.

The third pillar is the Coronagraph Instrument (CGI), a technology demonstration targeting a contrast ratio of 10^-9, meaning it can block a star's light to a level one billion times dimmer to reveal orbiting companions. Current ground-based and space-based coronagraphs achieve contrasts of roughly 10^-7 to 10^-8. If demonstrated at 10^-9 from space, CGI will establish the technology baseline for future direct-imaging flagship missions targeting Earth-sized planets in the habitable zones of nearby Sun-like stars.

wide-field infrared sensor array

the primary camera on the Roman Space Telescope, capable of imaging large areas of the sky in infrared wavelengths

baryon acoustic oscillations

regular, periodic fluctuations in the density of visible matter in the universe, used as a standard ruler to measure cosmic distances

dark energy equation-of-state

a parameter describing the relationship between dark energy's pressure and density, which determines how it affects the universe's expansion

gravitational microlensing

the temporary brightening of a background star caused by the gravity of a foreground object bending and focusing its light

Level 4 — Advanced

NASA's confirmation of an August 30, 2026 launch for the Nancy Grace Roman Space Telescope, nearly eight months ahead of the May 2027 readiness schedule, marks the culmination of a development history stretching back to the 2010 New Worlds, New Horizons decadal survey, which identified a Wide-Field Infrared Survey Telescope as the highest-priority new large space astronomy mission. Originally designated WFIRST, the observatory was renamed in 2020 to honour Nancy Grace Roman, NASA's first Chief of Astronomy and the institutional architect of the Hubble Space Telescope programme. The early launch reflects the completion of a successful thermal vacuum test campaign and launch vehicle integration review at Kennedy Space Center.

Roman's science architecture is built around three mutually reinforcing pillars. The dark energy programme deploys two complementary probes: a weak gravitational lensing cosmic shear survey mapping the distortion of billions of galaxy shapes, which constrains the growth rate of large-scale structure, and a spectroscopic baryon acoustic oscillation (BAO) survey providing an absolute distance scale. Together these are projected to constrain the dark energy equation-of-state parameter w to approximately 0.3 percent precision, sufficient to distinguish between a cosmological constant (w = -1) and dynamical dark energy models. Roman's sky coverage of approximately 2,200 square degrees at high galactic latitude will surpass all previous space-based photometric surveys by a wide margin.

The galactic bulge microlensing exoplanet census exploits Roman's high cadence, high angular resolution WFI imaging to monitor approximately 200 million stars simultaneously for the characteristic light curve signatures of planetary microlensing events. Population synthesis models predict detections of 1,400 to 2,500 bound planets predominantly at the snow line (1 to 10 AU), complementing Kepler's transit census which was most sensitive to short-period planets. Critically, Roman's sensitivity to isolated lens events will provide the first statistical census of free-floating planets (FFPs) down to approximately Earth mass, testing models of planet formation efficiency and dynamical ejection rates.

The Coronagraph Instrument (CGI) operates in a technology demonstration mode with the goal of achieving a post-processing contrast of 10^-9 in a dark hole within the instrument's inner working angle, approximately three to seven stellar radii. This is two orders of magnitude deeper than the best current space-based coronagraphs and represents the essential precursor capability for the Habitable Worlds Observatory (HWO), the next-generation flagship mission prioritised by the 2020 decadal survey for direct spectroscopic characterisation of terrestrial exoplanet atmospheres around Sun-like stars. A successful CGI demonstration would retire the primary technical risk standing between current capabilities and the search for biosignatures on nearby exoplanets.

decadal survey

a periodic report by the US National Academies that ranks astronomical science priorities and recommends missions for the next ten years