The European interplanetary station Hera recently sent back the first images from space taken as part of the first activation and testing of on-board instruments. The station was launched on October 7 to study the effects of the DART probe hitting the Dimorph asteroid. The activation of three different cameras took place on October 10 and 11. The resulting images of the Earth and Moon were taken from distances of 1.4–1.6 million km. The James Webb Telescope operates at approximately this distance from Earth.
Location of instruments on the platform of the Gera station. Image source: ESA
In the optical range, test shooting was carried out with two monochrome Asteroid Framing Cameras, AFC (indicated by the letter A in the diagram). The image of the Earth and Moon was taken on October 11 from a distance of approximately 1.6 million km. In the photo, the Earth is oriented with its north pole up, and the Sun illuminates the Pacific Ocean. AFC cameras are manufactured by the German company Jena-Optronik based on the ASTROhead celestial navigator. In addition to scientific images, the cameras will navigate by stars.
The image of the Earth and the Moon in the infrared range was taken by the Thermal Infrared Imager (TIRI, letter B in the diagram). The image was taken from a distance of 1.4 million km. The north of the planet is also directed upward, and we can see the East Coast of the United States and the Atlantic Ocean. The TIRI camera was manufactured by the Japanese company Meisei Electric for JAXA. The camera is based on an asteroid research instrument used during the Hayabusa 2 mission. The device will create a temperature map of asteroids, which will clarify their composition and surface variations (based on the dynamics of thermal distribution and thermal inertia).
The third image was taken by the HyperScout (H) hyperspectral camera, which was manufactured in the Netherlands by Cosine remote sensing. The image was taken from a distance of 1.6 million km and shows the Earth in false colors. HyperScout H will observe the Dimorph asteroid in colors inaccessible to the human eye and help determine the mineral composition of the asteroid. The hyperspectral camera covers the wavelength range of 650–950 nm, with colors encoded so that blue represents the shortest wavelength and red the longest.
The Hera station will reach the binary system of near-Earth asteroids Didyma and Dimorpha in October 2026. The Dimorph asteroid was rammed by NASA’s DART probe in October 2022, causing its orbit around Didymos to deviate. “Hera” must collect the maximum amount of information on the deflection and objects of impact, which will improve models for calculating the impact deflection of asteroids dangerous to the Earth.