Skip to main content

NASA’s Roman telescope could spot Earth-like planets

The James Webb Space Telescope might be grabbing all the headlines right now, but NASA has big plans for another space-based telescope too: The Nancy Grace Roman Space Telescope. Set to launch in 2027, Roman will survey the sky in the infrared wavelength to learn about big topics in cosmology like dark energy as well as perform a census of exoplanets. Now, NASA has shared more information about the kinds of planets that Roman could find, including the possibility it could take the first image of a Jupiter-like world.

Directly Imaging Distant Planets With a Coronagraph

Roman will be armed with a coronagraph instrument which is designed to block out light from very bright objects like stars to allow observation of the planets around them, opening the possibility of directly imaging planets. This is exciting because most exoplanets discovered now are detected indirectly, by looking at the star they orbit. Being able to image an exoplanet directly can give more information, for example about the planet’s atmosphere.

Artist's rendering of NASA’s Nancy Grace Roman Space Telescope.
NASA’s Nancy Grace Roman Space Telescope, named after NASA’s first Chief of Astronomy. NASA

“We will be able to image worlds in visible light using the Roman Coronagraph,” said Rob Zellem, an astronomer at NASA’s Jet Propulsion Laboratory (JPL) who is working on Roman, in a statement. “Doing so from space will help us see smaller, older, and colder planets than direct imaging usually reveals, bringing us a giant leap closer to imaging planets like Earth.”

This also opens up more possibilities in the type of planets that could be discovered. Most methods used to detect exoplanets currently find large, young planets which glow brightly, and are typically located far from their host star. These factors make them easier to spot using current methods. But Roman’s coronagraph could spot rocky, Earth-sized planets, perhaps even within the habitable zone of sun-like stars. In addition, it could view planets in the visible light wavelength as opposed to the infrared wavelength more commonly used now.

“To image Earth-like planets, we’ll need 10,000 times better performance than today’s instruments provide,” said Vanessa Bailey, an astronomer at JPL and the instrument technologist for the Roman Coronagraph. “The Coronagraph Instrument will perform several hundred times better than current instruments, so we will be able to see Jupiter-like planets that are more than 100 million times fainter than their host stars.”

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
Webb spots water vapor in a planet-forming disk
An artist's concept portraying the star PDS 70 and its inner protoplanetary disk.

One of the big open questions about Earth and how life formed here is where the planet's water came from. Water is essential to life as we know it, but many scientists think that water did not originally form on Earth -- rather, it may have been carried here by asteroids. Recently, though, astronomers have discovered water vapor in the planet-forming region of a star, suggesting that future planets which form here might have access to water right from the start.

The study used the James Webb Space Telescope to look at star PDS 70, which is cooler and much younger than our sun. The star has two gas giant planets orbiting it, but it is also still forming planets and has two protoplanetary disks of dust and gas swirling around it. The inner disk, which is in a region comparable to the distance of the Earth from the sun, is where the water vapor was detected.

Read more
James Webb spots ancient dust that could be from the earliest supernovas
This image highlights the location of the galaxy JADES-GS-z6 in a portion of an area of the sky known as GOODS-South, which was observed as part of the JWST Advanced Deep Extragalactic Survey, or JADES.

Dust might not sound like the most interesting of topics, but to a certain set of astronomers, it's thrilling. Researchers recently used the James Webb Space Telescope to identify grains of dust from the early universe, which could have been produced by the earliest supernovas.

James Webb is a powerful tool because it allows researchers to identify extremely distant, and therefore extremely old, galaxies. Webb can be used to not only identify these early galaxies but also to take spectra from them, which can reveal their chemical composition by seeing which wavelengths of light they absorb. As part of a survey called JWST Advanced Deep Extragalactic Survey or JADES, Webb's NIRCam instrument took this image of a region of the sky called GOODS-South. Within that image, researchers used Webb's NIRSpec instrument to look at the spectra of early galaxies like JADES-GS-z6.

Read more
Saturn as you’ve never seen it before, captured by Webb telescope
Saturn captured by the James Webb Space Telescope

NASA has shared a gorgeous image of Saturn captured recently by the James Webb Space Telescope (JWST).

Webb’s first near-infrared observations of the second largest planet in our solar system also show several of Saturn’s moons: Dione, Enceladus, and Tethys.

Read more