NASA is getting ready to send a new eye into space one designed not just to take beautiful pictures, but to help answer some of the biggest questions about how the universe actually works.
The Nancy Grace Roman Space Telescope has cleared its latest major review and is now moving into the final preparations for launch. NASA is targeting August 30 for liftoff from Kennedy Space Center in Florida aboard a SpaceX Falcon Heavy rocket. Mission managers from NASA and SpaceX completed the flight readiness review on August 21, followed by the final launch preparations.
Roman is different from the James Webb Space Telescope in one important way: it is designed to see a much wider portion of the sky at once.
Its Wide Field Instrument will allow astronomers to survey huge areas of the universe in a single observation. NASA says Roman will have a field of view at least 100 times larger than Hubble’s, while still producing images with a sharpness comparable to Hubble.
That wider view could be especially useful for studying things that are difficult to understand because they are spread across enormous distances and over vast stretches of time.
One of the biggest targets is dark energy, the mysterious phenomenon believed to be driving the accelerating expansion of the universe. Scientists still do not know exactly what dark energy is, or whether our current understanding of gravity tells the whole story. Roman will study the distribution and evolution of galaxies and other cosmic structures to help narrow down the possibilities.
Dark matter is another major part of the mission. Scientists cannot see dark matter directly, but they can detect its gravitational influence through the way it affects visible matter and light.
And then there are planets.
Roman is expected to discover a huge number of exoplanets worlds orbiting stars beyond our Sun. NASA says its observations could identify as many as 100,000 new exoplanets, giving scientists a much broader picture of how planetary systems form and evolve.
The telescope will also carry a technology demonstration that could eventually help astronomers directly study planets around other stars by blocking out the overwhelming light of their parent stars.
That is where Roman could complement, rather than replace, Webb.
The James Webb Space Telescope is exceptionally powerful when it comes to examining individual objects in great detail. Roman is designed more like a cosmic survey camera, repeatedly scanning enormous areas of the sky and building a much wider map of the universe.
NASA has already completed several important steps in preparation for the launch. Engineers carried out a full launch-day rehearsal on August 20, and the flight readiness review was completed the following day.
If everything remains on schedule, Roman will leave Earth on August 30 and travel to a special location about 1.5 million kilometres from Earth known as the second Sun-Earth Lagrange point, or L2. From there, its position will give the telescope a stable vantage point for observing the cosmos.
For people on Earth, the launch may look like another rocket heading into the sky.
But what comes afterwards is far more interesting.
Roman will spend years looking outward, collecting an enormous amount of information about galaxies, stars, planets and the invisible forces shaping the universe.
And some of its most important discoveries may turn out to be things scientists are not expecting to find at all.
