The James Webb Space Telescope has continued to unveil the beauty and mystery of the cosmos since delivering its first images in July last year – but the mission to deploy the next big space telescope is already well underway.
The Nancy Grace Roman Space Telescope will be the next major space telescope to launch after the deployment of NASA’s last telescope, which itself was the successor to the still-active Hubble Telescope.
Roman’s launch will usher in “a new era for astronomy”, one of the European Space Agency (ESA) scientists working on the project told Euronews Next; it will gather more data than any other NASA mission launched before and attempt to answer some of the biggest questions in astrophysics.
Scheduled to be launched no later than 2027, it will be able to capture “a more panoramic view of the universe and enable more statistical studies”, explained Marco Sirianni, ESA’s science operations development manager who is working on the project with NASA.
While this is a NASA-led mission, ESA brings some of the technology and expertise to the mission, in return for access to the unprecedented amount of data it is donating. will provide.
Here’s a look at what to expect from NASA’s next big space telescope.
How will Roman be different from Hubble and James Webb?
While Hubble and Webb are extremely good at zooming in to get a detailed look at small parts of the sky, Roman is going to have a much wider field of view.
It will be able to create infrared images 200 times larger than Hubble while providing the same level of rich detail with its similarly sized 2.4 meter diameter mirror.
So while it will be able to produce “exquisite” images, which we’ve grown accustomed to from Hubble and Webb, it will primarily be “a dedicated surveying telescope,” Sirianni said.
“In order to search for the population of stars in a nearby galaxy, which is very large for Hubble’s field of view, we have to assemble and make mosaics of very different planes. With Roman, we can take a picture of the entire galaxy in one fell swoop,” he says.
For example, a recent “mosaic” of our neighboring galaxy Andromeda was assembled with 400 individual images taken by Hubble. Roman will be able to paint the same vast image with the same level of detail with just two images. And those much larger images mean there will be an unprecedented amount of data collected.
“Just to give you an idea, in 30 years of running Hubble, we’ve gathered something like 170 terabytes of data,” Sirianni explained. “For Webb, we plan to have 1,000 terabytes in five years. And for Roman’s nominal 5-year lifespan, we plan to have 20,000 terabytes.”
Eventually, it will gather data from billions of galaxies to create a “3D model of the universe”.
Answering Cosmic Mysteries
With this panoramic view of the universe, NASA and its partners hope to answer some of the biggest questions facing astrophysics.
One of the objectives is to test Albert Einstein’s theory of general relativity, which is well tested on the scale of our solar system for example, but less so on larger cosmological scales.
Visible matter in the universe should, according to the theory, slow down the expansion of the universe, so scientists attribute the speed of expansion of the universe to a mysterious component – dark energy – which, according to them, represents about 68% of the universe. .
Roman will provide us with data to accurately measure the position and distance of millions of galaxies and help us understand the rate of expansion of the universe in different regions.
Ultimately, the results will tell us if Einstein’s theory of gravity needs to be modified.
Census of exoplanets
Another of Roman’s main goals is to spot thousands of new exoplanets in our galaxy, using a technique called gravitational microlensing.
“If two stars align with each other, the one in front will distort and magnify the light of the star behind. And if the star in the foreground has a planet, we’ll see the impact of that planet on the starlight behind it,” Sirianni said.
Since Roman will count billions of stars, it will provide a “very good count of how many stars will have exoplanets,” he added.
Not only will it spot new exoplanets, but Roman will carry a second main instrument – called a coronagraph – which aims to image exoplanets close to their parent star. “It’s a very difficult technique because starlight has to be removed – it’s an order of magnitude brighter than the objects you want to study, the neighboring planet,” Sirianni said.
Roman’s coronagraph will attempt to directly capture large planets similar to Jupiter, performing live corrections to improve image quality.
It will be a demonstration instrument – and if proven effective, it will form the basis of technology for use on future space observatories that attempt to directly image Earth-like planets in the habitable zone of their parent star. .
ESA’s contribution to Roman
ESA brings three key pieces of technology to the Roman mission, in exchange for access to data and a seat at the table during the mission.
The space agency will provide “star trackers,” small telescopes in the spacecraft that constantly determine its position in the sky by tracking the stars. Then it will provide batteries to help power the spacecraft before its solar panels are deployed.
And finally, it will also provide detectors for the onboard coronagraph.
Additionally, ESA’s own mission to measure the expansion of the universe and learn more about dark energy will be launched this summer.
The Euclid space telescope will collect the information which will then be complementary to the data collected by Roman.
Like ESA’s contribution to Roman, NASA also makes small contributions to the Euclid mission.