- 1Aurora Technology B.V. for ESA, European Space Astronomy Centre, Villanueva de la Canãda, Spain
- 2Instituto de Astrofísica de Canarias, La Laguna, Spain
- 3Department of Astrophysics, University of La Laguna, La Laguna, Spain
- 4Space Sciences Laboratory at University of California, Berkeley, CA, USA
- 5Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland
- 6Department of Mechatronics, Optics and Engineering Informatics, Budapest University of Technology and Economics, Budapest, Hungary
- 7ESA, European Space Astronomy Centre, Villanueva de la Canãda, Spain
- 8Astronomical Institute of the Romanian Academy, Bukarest, Romania
- 9University of Craiova, Craiova, Romania
The Hera mission was launched on 7 October 2024 and will reach its destination, the binary asteroids Didymos and Dimorphos, in late 2026. Hera carries the hyperspectral imager Hyperscout-H. Its sensor consists of 2048 × 1088 pixels arranged in macro pixel blocks of 5 × 5 pixels. The 25 pixels of each block are covered with filters in 25 different wavelengths where the center response ranges from 657 to 949 nm. Therefore, each of the 2048 × 1088 micro pixels provides brightness information for one wavelength, and the actual macro pixel resolution is only about 409 × 217 pixels. Any simple interpolation approach between micro pixels is strongly affected by pixel-to-pixel variations in spectra and by varying albedo and shading effects caused by surface inclination. This makes the resultant spectra very noisy.
To retrieve more accurate spectra with higher spatial resolution, we have developed a family of novel demosaicing methods. We separate the spectrum at each micro pixel into a normalized spectrum and a brightness scaling factor. Ratios of measured values from adjacent pixels are used to iteratively compute the normalized spectra, which are then brightness scaled to reproduce the measured values. This approach allows replenishment of the complete data cube of 2048 × 1088 × 25 pixels.
Four days after launch, the three cameras aboard Hera acquired images of the Moon and the Earth. Because of the large distance, the resolution of these images was limited. However, the Hyperscout-H images of the Earth demonstrated that color images at full micro pixel resolution can be reconstructed from the replenished data cube.
On 12 March 2025, Hera will perform a fly-by of Mars, and images of Mars and Deimos will be acquired from distances of about 20,000 and 1,000 km, respectively. Hyperscout-H is planned to acquire one image with both Mars and Deimos in the field of view. We will apply our demosaicing methods to replenish the complete data cubes and reconstruct color images at full micro pixel resolution.
How to cite: Grieger, B., de León, J., Goldberg, H., Kohout, T., Kovács, G., Küppers, M., Nagy, B. V., Popescu, M., and Prodan, G.: Superresolution color images of Mars and Deimos acquired by the Hyperscout-H hyperspectral imager aboard the Hera mission, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7092, https://doi.org/10.5194/egusphere-egu25-7092, 2025.
