NASA announced today the selection of a new space telescope that will explore the cold, dusty universe in far‑infrared light, providing the ability to view cosmic objects and events at wavelengths that are otherwise invisible with existing telescopes. The Jet Propulsion Laboratory, which Caltech manages for NASA, will develop and operate the $1 billion observatory named PRIMA (the Probe far-Infrared Mission for Astrophysics). Caltech's IPAC will serve as the mission science center, where raw data from the telescope is received, processed, and archived for use by astronomers seeking to answer some of the universe's deepest mysteries. IPAC will also be responsible for scheduling astronomers' time and use of the telescope.
"PRIMA represents a giant leap for far-infrared astronomy, born from decades of daring ingenuity at Caltech and JPL," says Caltech President Ray Jayawardhana, the Sonja and William Davidow Presidential Chair and professor of astronomy. "By combining detector technology pioneered by our colleagues with deep scientific expertise across Caltech, JPL, and IPAC, PRIMA will help reveal fundamental cosmic processes that have long been hidden from view. We are delighted to play such a vital role in bringing this mission to life, providing scientists with new tools to probe our restless universe and giving people everywhere new views of countless cosmic splendors."
PRIMA has been specially designed and engineered such that its telescope and detectors are cooled to hundreds of degrees below zero, significantly reducing thermal "noise" that can muddy images. As a result, PRIMA is orders of magnitude more sensitive than previous far-infrared space missions, and it will produce images with unprecedented sharpness, enabling astronomers to perform breakthrough science on the origins of planetary atmospheres, the evolution of galaxies and supermassive black holes, and the formation of dust and heavy elements in the universe, among other topics.
The mission features a cryogenically cooled 1.8‑meter telescope, an imaging polarimeter (PRIMAger) to map large areas of the sky, and a high‑resolution spectrometer (FIRESS) to conduct multimode spectroscopy. With this suite of instruments, PRIMA will investigate the universe at far-infrared wavelengths ranging from 24 micrometers (one-third the thickness of a human hair) to 235 micrometers (roughly the thickness of two stacked pieces of paper). The observatory will provide new insight into a universe that is otherwise hidden at visible wavelengths—helping scientists to study the formation of stars and planetary systems, trace the evolution of galaxies across cosmic time, and characterize the composition of exoplanet atmospheres and solar system bodies.
PRIMA is NASA's first "probe-class" astrophysics mission. These kinds of missions, recommended in the Astro 2020 Decadal Survey led by Caltech's Fiona Harrison, the Harold Rosen Professor of Physics, fill the gap between Explorer-class missions like SPHEREx and flagship mission like the Nancy Grace Roman Space Telescope.
"The PRIMA mission is humanity's next window into the deep universe. It will unveil the obscure across cosmic time to better understand the formation of planets, stars, black holes, and even how water on Earth came to be," said Nicky Fox, associate administrator, Science Mission Directorate, NASA Headquarters in Washington, in today's announcement.
Caltech and JPL have been central to PRIMA's conception, technology development, and planned operations. Leveraging its decades of experience in infrared astrophysics missions, JPL will lead mission architecture, systems engineering, and the integration of the spacecraft and payload.
Caltech and JPL scientists pioneered the superconducting microwave kinetic inductance detectors (MKIDs/KIDs) that enable PRIMA's ultrasensitive far‑infrared cameras and spectrometers. MKIDs and KIDs were invented by Jonas Zmuidzinas (BS '81), the Merle Kingsley Professor of Physics at Caltech, and JPL engineer Rick LeDuc, in 1999. The two first figured out the key to using superconducting materials to detect far-infrared light at a Peet's coffee shop near Caltech.
Over the next few years, Zmuidzinas and LeDuc, in collaboration with colleagues at Caltech and JPL, worked out other details in the detectors' design. In 2007, the detectors were installed and successfully tested at the now-decommissioned Caltech Submillimeter Observatory (CSO) near the summit of Maunakea in Hawai'i. The detectors were subsequently used in a number of other ground-based and balloon-borne instruments.
In the past five years, the Caltech-JPL research team, including members of JPL's Microdevices Laboratory (MDL), have focused on taking KIDS arrays to the next level, engineering them to have the exquisite sensitivity required for a space mission like PRIMA and to withstand the rigors of the space environment. The effort has led to prototype KID arrays that demonstrate readiness for flight onboard PRIMA.
"Our program of developing these detectors over three decades has led to PRIMA," says Zmuidzinas, who, this past January, was awarded the 2026 James Craig Watson Medal from the National Academy of Sciences for his novel detector technologies. "Historically, humanity has been fascinated by the universe, by the cosmos, and that enthusiasm hasn't waned. It's a source of inspiration. PRIMA represents something that occurs rarely in astronomy: In this less-explored wavelength band, the far infrared, we have a chance to leap forward in sensitivity by about a factor of a thousand. That's very rare."
For its part, IPAC, as the science center for PRIMA, will support both the PRIMA team and the entire science community with planning, scheduling, calibration, and science data processing. The PRIMA data will be hosted at the Infrared Science Archive (IRSA), joining a collection of over 20 NASA missions already maintained by this archive at IPAC.
For this work, IPAC will leverage its experience on several missions—including NASA's Spitzer Space Telescope, a JPL-managed infrared observatory that operated from 2003 to 2020; NASA/JPL's Caltech-led SPHEREx, launched in March 2025 to map the entire sky in infrared; and the European Space Agency's Herschel—extending the knowledge gained from those missions to this next-generation observatory. This follows IPAC's long history of supporting operations for observatories both in space and on the ground.
"PRIMA will be the next in line after four decades of NASA missions that IPAC has supported, going back to IRAS [Infrared Astronomical Satellite] in the 1980s. We are looking forward to this next challenge," says Rachel Akeson (PhD '97), the deputy director of IPAC. "We are excited to work with the science team and our colleagues at JPL to make this mission happen and to make this unique data accessible to the entire astronomy community."
Once it is fully operational, about 75 percent of PRIMA's observing time will be available to the general science community through a peer-review proposal process. The team has already received nearly 200 ideas for using PRIMA data, submitted by over 400 astronomers.
"I am particularly excited about how PRIMA will help us discover and understand the role of powerful molecular outflows in galaxies over cosmic time, and how they shape star formation and the growth of supermassive black holes in the centers of galaxies," says Lee Armus, a PRIMA co-investigator and science operations lead at IPAC. "Galaxies do not live sedentary lives. They grow over time through the accretion of gas and through mergers with other galaxies. They can also go through periods of enhanced activity where stars are produced at rates 10 to 100 times faster than normal, and their central massive black holes can 'turn on' and drive material outwards. These molecular outflows were studied in the far-infrared with the Herschel Space Observatory in a handful of local galaxies. PRIMA will allow us to study hundreds to thousands of galaxy outflows, mapping the demographics and revealing the physics behind this important piece of galaxy evolution."
With today's confirmation, PRIMA will advance into detailed design and technology maturation, with a launch target date in the 2030s. NASA expects to release further details on mission milestones, international partnerships, and opportunities for the broader scientific community in coming months.
Artist rendering of the PRIMA Observatory.
Credit: NASA/JPL-Caltech
