On the Nancy Grace Roman Space Telescope: To infinity and beyond!

Set to launch on the 30 August 2026 at NASA’s Kennedy Space Center in Florida (and probably has by the time you read this article), the Nancy Grace Roman Space Telescope (or ‘Roman Telescope’) is set to tackle profound astrophysics questions in the areas of dark energy, dark matter, and exoplanets, as stated by NASA. It’s named after NASA’s first Chief of Astronomy, Dr. Nancy Grace Roman. Not only known as the ‘mother’ of the Hubble Telescope, she was a driving force behind NASA’s ‘Great Observatories’ program. For curious minds, more information is available at science.nasa.gov. 

The Roman telescope contains two new instruments: the Wide Field Instrument and the Coronagraph. The Wide Field Instrument is a 300-megapixel infrared camera not only matching the sensitivity of Hubble’s cameras, but with a field of view 100 times larger, according to the University of Arizona. Over the first five years of observations, Roman is expected to image over 50 times as much sky than Hubble covered in its first 30 years. 

Before we delve into why the discoveries of the Nancy Grace Roman space telescope are important, we must first understand dark matter, dark energy and exoplanets

As for its Coronagraph, NASA says it will be far more powerful than any other ever flown, demonstrating technology that eliminates the glare of nearby stars and allows astronomers to directly image planets in orbit around them. The instrument itself is made up of a system of masks, prisms, detectors, and even self-flexing mirrors to perform direct imaging. It points the way to technologies for even larger space telescopes with its ability to capture light from exoplanets and other stars. 

Before we delve into why the discoveries of the Nancy Grace Roman space telescope are important, we must first understand dark matter, dark energy and exoplanets, as well as why we are eager to discover more on them.  

NASA defines exoplanets as planets that exist outside our solar system. There are currently about 6,000 confirmed exoplanets, a number rapidly increasing, compelled by our curiosity about life beyond Earth. According to NASA, the future of exoplanets will focus majorly on discovering rocky planets like Earth, then investigating their biosignatures (defined as any evidence of past or present life). Reported by USAHerald, Roman is expected to discover thousands of planets and may identify roughly 100,000 through its broader surveys. 

So, what exactly is dark matter? Scientists aren’t entirely sure either: they have investigated it for the past century and have still struggled to pin it down. They have estimated regular matter only makes up about 5% of the universe, with 27% being dark matter, and the rest being dark energy.  

The difference between dark and regular matter is dark matter doesn’t interact with the electromagnetic spectrum, including visible light. So, it doesn’t absorb, reflect, or emit any light. Whilst it doesn’t interact with light, the gravity from dark matter is able to reflect light from distant galaxies, which creates an effect named gravitational lensing. Dark matter has mass and temperature, hence scientists have theorized dark matter consisted of more than one matter or particle, with top contenders being Weak Interactive Massive Particles (WIMPs), Axions, and Primordial Black Holes.  

National Geographic predicts Roman, with its Wide Field Instrument, will investigate dark matter by observing hundreds of instances of gravitational lensing, allowing scientists to then analyse the warped light for tiny distortions caused by dark matter.  

Dark energy, although similar in name to dark matter, serves a fundamentally different purpose. The word ‘dark’ in both terms signifies they are invisible to us as they don’t absorb, emit or reflect light. According to the Centre for Astrophysics, dark matter could be roughly conceptualized as “invisible glue”, while dark energy is the force behind the universe expanding at an accelerated rate. Dark matter pulls galaxies together, and dark energy pushes them apart. And like dark energy, it’s one of the greatest enigmas in the astrophysics field. 

Recent results even hint dark energy may be changing over time – and Roman will hopefully shed more light on dark energy and test our model of the universe using several techniques, such as Baryon Acoustic Oscillations (detecting vestiges of sound waves), Type La Supernovae (observing exploding stars across time and space), and weak lensing (a type of gravitational lensing besides strong lensing). 

Interestingly, the Roman telescope was initially not meant for observing galaxies but was instead a spy satellite. A product of the National Reconnaissance Office, it was abandoned in 2005. It made its way to NASA in 2011, when spy officials offered its leftovers to NASA for free, and has now become what is soon to be a crucial tool to new scientific discoveries.  

With a primary mission lifetime of five years, and a potential extended mission of another five years, Roman has a long and ambitious road ahead

We are expecting to see Roman’s first images shared with us by early 2027. With a primary mission lifetime of five years, and a potential extended mission of another five years, Roman has a long and ambitious road ahead. As it unveils more of the vast, largely unexplored cosmos, we would do well to pay it close attention.