A few months ago, the American Space Agency (NASA) presented a new camera whose nature may surprise you. This camera, whose aim is to uncover the secrets of the formation of galaxies and the nature of dark matter, has a sensor of only a few dozen pixels.
A microcalorimeter spectrometer
Launched at the end of 2021, the James Webb space telescope is characterized by an image definition of 122 megapixels. However, NASA’s latest camera is equipped with a sensor of only 36 pixels. Called Resolve, this equipment is in reality a microcalorimeter spectrometer capable of measuring minute temperature variations. However, the device does not just capture images. In fact, its detector makes it possible to measure the temperature of each X-ray that hits it. In other words, Resolve ensures unprecedented precision for chemical composition analysis observed objects, notably supermassive black holes.
The device in question is the central element of NASA’s X-Ray Imaging and Spectroscopy Mission (XRISM), carried out in collaboration with the European Space Agency (ESA) and the Japanese Space Agency (JAXA). The mission has already started, the satellite having been launched from the Tanegashima space center (Japan) in September 2023. Furthermore, you should know that the mission also integrates other equipment : the Xtend, an X-ray imager.
What is NASA hoping for?
“XRISM will provide the international scientific community with new insight into the hidden X-ray sky. We will not only see X-ray images of these sources, but also study their compositions, movements and physical states. »declared Richard Kelley, the principal investigator of the mission at NASA’s Goddard Space Flight Center in a press release published in January 2024.
Each pixel of the Resolve spectrometer generates a spectrum of visual data that covers a wide energy range, i.e. from 400 to 12,000 electron volts. The device can therefore perceive the movements of elements within a target with an almost three-dimensional perspective. In fact, the spectrometer is capable of identify the elements present in a specific region of space, to evaluate their temperature, but also to identify their physical properties or the gases and materials found there.
For NASA, mapping the movements of matter with unprecedented precision can open new doors in the field of space exploration in general. This will make it possible, in particular, to understand hot gas flows in galaxy clusters or to follow the movement of elements in what remains of supernova explosions.
