A bus-sized telescope with X-ray vision flew into space Thursday morning in Japan.
It is not alone. Along for the ride was a robotic moon lander the size of a small food truck. The XRISM and SLIM missions will soon separate, one to spy on some of the hottest spots in our universe, the other to help Japan’s space agency JAXA test technologies used on large-scale lunar missions. Landing in the future.
Rising from the shores of Tanekashima, an island in the southernmost part of the Japanese archipelago, it was beautiful as a Japanese H-IIA rocket soared over a distant launch pad and was stopped by a few clouds in the blue sky. About 47 minutes after liftoff, launch officials were shown on a live video stream in the mission control room celebrating the arrival of the XRISM and SLIM spacecraft toward their respective cosmic destinations.
The X-ray Imaging and Spectroscopy Mission – abbreviated XRISM (and pronounced “Chrysm”) – is the launch’s primary passenger. From an orbit more than 350 miles above Earth, XRISM will study exotic environments that emit X-ray radiation, including objects orbiting black holes, clusters of blistering plasma, and remnants of exploding massive stars.
Data from the telescope will shed light on the motion and chemistry of these cosmic spots with a technique called spectroscopy, which extracts information about the composition of sources from changes in their brightness at different wavelengths. This technique gives scientists a glimpse into the universe’s highest energy phenomena and adds to astronomers’ detailed, multi-wavelength picture of the universe.
XRISM’s spectroscopy will “reveal energy flows between celestial objects at various scales” with unprecedented resolution, Makoto Tashiro, the telescope’s principal investigator and an astrophysicist at JAXA, wrote in an email.
The Japanese space agency is carrying out this mission in collaboration with NASA. The European Space Agency contributed to the telescope’s construction, meaning astronomers from Europe will be allocated part of the telescope’s observing time.
XRISM is a reconfiguration of the Hitomi mission, a JAXA spacecraft launched in 2016. The Hitomi telescope went out of control a few weeks into its journey, and Japan lost contact with the spacecraft.
“It’s a devastating loss,” said Brian J. Williams, an astrophysicist at NASA Goddard Space Flight Center. The little data gathered from Hitomi was a wonderful taste of what such a mission could offer.
“Since X-ray astronomy is the future, we realized that this mission needed to be replicated,” said Dr Williams.
Unlike other wavelengths of light, cosmic X-rays can only be detected from above the Earth’s atmosphere, shielding us from harmful radiation. XRISM joins other X-ray telescopes already in orbit NASA’s Chandra X-ray ObservatoryIt was launched in 1999 and joined the party in 2021 as NASA’s Imaging X-ray Polarimetry Explorer.
What sets XRISM apart from those missions is an instrument called Resolve, which must be cooled to a fraction above absolute zero so that it can measure small changes in temperature when X-rays strike its surface. The task force expects the resolved spectroscopic data to be 30 times sharper than the resolution of Chandra’s instruments.
Leah Corrales, an astronomer at the University of Michigan who was selected as a participating scientist for the mission, sees XRISM as “a pioneering vehicle” that represents the “next phase of X-ray observations.” To gain insight into the chemical evolution of our universe through its sophisticated spectroscopy, Dr.
European Space Agency astronomer Jan-Yve Ness, who will manage the proposal selection process for Europe’s dedicated observing time, said the high quality of data collected by XRISM’s spectroscopy will make it feel like seeing these extreme environments for themselves.
“I look forward to the spectral revolution,” he said, adding that it will set the stage for even more ambitious X-ray telescopes in the future.
XRISM also has a second tool called Xtend that works concurrently with Resolve. During Resolve Zoom, Xtend zooms in, giving scientists complementary views of the same X-ray sources over a larger area. According to Dr. Williams, Xtend is less powerful than the imager on the older Chandra telescope. Some of the most remarkable views of the X-ray universe Until today. But X-ray vision would photograph the extended universe with resolution comparable to the way our eyes perceive it.
Once XRISM is in low-Earth orbit, researchers will operate the instruments and conduct performance tests over the next few months. Scientific activities will begin in January, but initial studies of data may not appear for a year or more, Dr. Tashiro said. Ahead of any discovery, he’s excited to see the instruments in action, adding, “We’ll definitely see a new world of X-ray astronomy once they’re up and running.”
Above all, Dr. Williams is looking forward to the “unknowns” that XRISM might discover. “Every time we launch a new capability, we discover something new about the universe,” he said. “What will he have? I don’t know, but I’m interested in finding out.
The Smart Lander for Lunar Exploration, or SLIM, is the next robotic spacecraft headed for the moon, but may not land next.
A long, round trip that requires SLIM less propellant would take at least four months. The lander will take several months to reach lunar orbit, then spend a month orbiting the moon before attempting to land near the moon’s nearest Shioli Crater.
That means two U.S. spacecraft, powered by Pittsburgh’s Astrobotic Technology and Houston’s Intuitive Engines, will be able to beat SLIM to the surface, launching later this year and taking more direct paths to the moon.
Although SLIM carries a camera that can identify the composition of rocks surrounding the landing site, the mission’s primary objectives are not scientific. Rather, it is intended to show a precision navigation system that aims to be set within a football field’s length of the target site.
Currently, lunar landers can attempt to land within several miles of a selected landing site. For example, the landing zone for India’s Chandrayaan-3 spacecraft, which successfully landed on the moon’s south pole last month, is seven miles wide and 34 miles long.
Vision-based systems in many landing craft are limited because space-hardened computer chips have only one-hundredth the processing power of top-of-the-line chips used on Earth, JAXA said in its press kit.
For SLIM, JAXA developed image-processing algorithms that can run quickly on slow space chips. As SLIM approaches its landing, a camera will help the spacecraft land on the lunar surface; Radar and lasers measure the spacecraft’s altitude and downward speed.
Because of the risks of an accident that come with current systems, lunar landers are usually directed toward flat, less interesting terrain. A more precise navigation system could help future spacecraft land closer to rugged terrain of scientific interest, such as craters containing frozen water near the moon’s south pole.
At launch, the SLIM weighed more than 1,500 pounds; Two-thirds of the weight is propellant. In contrast, the Indian lunar lander and its small rover weighed about 3,800 pounds, and the accompanying propulsion module added 4,700 pounds from Earth orbit to the Moon.