NASA researchers gathered on July 29 to present updated information about the Nancy Grace Roman Space Telescope, the agency’s next major observatory, which will join legendary ones like the Hubble Space Telescope and the James Webb Space Telescope.
The press conference was marked by positive news. The Roman Telescope, valued at US$4 billion, is scheduled to launch on August 30, at 7:26 am EDT (11:26 am GMT), aboard a SpaceX rocket. The team reported that the schedule is nine months ahead of schedule.
Jeremy Perkins, integration and test scientist for the Roman Telescope, said during the briefing at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, that the observatory will soon be launched, tested, have its deployable aperture lid open, observe the sky and send data to Earth for the first time.
The news came days after NASA announced that the Roman was fueled with hydrazine, an efficient but toxic and unstable fuel. For this reason, the agency is looking for alternatives to stop using this substance, but it is still widely used while there is no suitable substitute.
For the Roman Telescope, a large amount of hydrazine is essential, as Perkins explained for different reasons.
First of all, it is important to know that Roman will be heading to Lagrange Point 2 (L2), a position of gravitational stability about 1.6 million kilometers away, located between the Earth and the Sun. This is a preferred area for observatories, as it allows the spacecraft to be oriented in a way that protects its instruments from heat, while the solar panels continue to receive sunlight for energy. The James Webb Space Telescope (JWST), for example, is also at L2.
On the way to L2, Roman will need to consume part of its fuel to make route corrections and ensure that it is heading to the correct destination.
“We performed a final orbital insertion around the 100th day to achieve our definitive orbit around L2,” Perkins said. “After that, we have enough fuel for all the current disposal and station keeping maneuvers that will be necessary for five years or more.”
With Roman already fueled, the next step is to attach it to SpaceX’s Falcon Heavy rocket, which will take it beyond the Earth’s atmosphere.
Jackie Townsend, Roman’s project manager, informed during the conference that “encapsulation”, the process of installing the observatory in the fairing that will transport it to orbit, will take place in three weeks.
Regarding what will happen after launch, there is a way to visualize expectations.
When comparing Roman to the Hubble Space Telescope, it’s important to note that scientists predict the former will generate more than 500 terabytes of data per year. In contrast, Hubble, over its roughly 35 years of operation, has produced a total of 400 terabytes.
“Roman has, broadly speaking, the same sensitivity and clarity of vision as Hubble, but can map the sky much more quickly,” said Julie McEnery, senior scientist for the Roman project, at the conference. “A month of observations to survey our Milky Way galaxy would take about a century with Hubble.”
“It would take more than half a million 4K TVs to fully display a single image of Roman in our largest survey,” reported McEnery. “To get a sense of the scale, these televisions would cover 45 city blocks of Manhattan.”
What about Roman’s comparison to JWST? Although the Roman Space Telescope has some near-infrared capabilities thanks to its impressive Wide-Field Instrument (WFI), it can’t match JWST’s ultrasensitive infrared sensors. Its advantage, however, lies in the panoramic view, as a Roman image would be about 50 times wider.
“Webb was designed to probe the universe with great depth and extreme sensitivity, allowing us to discover rare elements in the early universe,” McEnery explained about JWST. “However, we need Roman to locate rare elements in the nearest universe.”
As an example, McEnery mentioned the “little red dots,” elusive objects that appear repeatedly in JWST images of the ancient universe. The key to understanding these objects is to find as many as possible. However, due to JWST’s extremely magnified images focused on the distant universe, it cannot map many of them at once. The Roman, in turn, was built precisely for this task.
With all this data available, the possibilities for discoveries are vast. One of Roman’s instruments, called the coronagraph, is expected to revolutionize exoplanet research, while the WFI (Wide Field Instrument) will scan the cosmos to record approximately 2 billion galaxies during the telescope’s main survey.
“I see this as doing magic with physics. We are taking advantage of the wave properties of light to cancel out the brightness of a star, thus allowing us to photograph planets next to it,” described McEnery.
Understanding the dynamics of as many galaxies as possible will help scientists unravel the complexities of dark matter and dark energy. We cannot observe the dark universe directly, but we can notice how it influences its visible portion. These are just some of the expected results from Roman’s research. As the team has repeatedly indicated and as most observatory teams tend to suggest, the best discoveries will be the unexpected ones.
Even when considering other technological advances, the principle remains valid. When the internet was created, its inventors probably did not anticipate innovations like Facebook or Spotify, and when the first video game appeared, the concept of an open-world RPG may have seemed unattainable.
“When we built Hubble and Webb, we were looking for distant galaxies in the most remote corners of the universe. However, because we have Hubble and Webb, we are able to track asteroids that would pose a threat to Earth or future outposts on the lunar surface,” said Shawn Domagal-Goldman, director of the astrophysics division at NASA Headquarters, during the conference. “These were impossibilities that are now barely possible and sometimes routine.”
Perhaps what Roman has in store for us could lead to the next generation of his name, as Townsend mused.
Roman is named after Nancy Grace Roman, a pioneering figure in her field who was the first female executive at NASA and also the agency’s first chief of astronomy. She is often known as the “mother of Hubble” due to her significant contributions to the telescope and her groundbreaking work in satellite research. Furthermore, it helped lay the foundation for exoplanet science decades before the first discovery of one.
“The next Dr. Nancy Grace Roman, sitting in a classroom somewhere next year, will be studying our data and will hopefully be infected by an enthusiasm for science and go on to transform the world in the same way that Dr. Nancy Grace Roman did,” said Townsend.
