SpaDeLab - Space Debris Laboratory of the University of Coimbra

We present the SpaDeLab - Space Debris Laboratory, a laboratory for the study of space debris (SDs) analogs born out of an interdisciplinary team combining astronomy, astronomical instrumentation, surface and mechanical engineering.

Detecting and cataloguing space debris (SDs) is vital in order to ensure the safety of space assets. However, it is equally vital to identify their composition and estimate their sizes and shapes accurately. The impact energies of SDs depend on these parameters. To estimate the sizes of SDs, crude assumptions of their reflectivity as a function of the Sun-debris-observer angle, known as the phase-function F(φ), are used, potentially leading to large errors.

Making use of the existing spectroheliograph at the Geophysical and Astronomical Observatory of the University of Coimbra (OGA), with its moving system of mirrors (coelostat), we have redirected the solar light into a second room where an object can be suspended with controlled rotation and axial orientation. Its reflected light is analysed along a moving arm holding a CCD camera and a photometer equipped with astronomical standard broadband filters (Jonhson BVRI and Sloan g’r’i’) to fully measure its brightness (magnitude) phase-function.

With SpaDeLab we are now able to perform a systematic study of different shapes and different compositions of space debris analogs, both from off-the-shelf and from 3D-build objects, with different coatings, different rugosities, and different rotational properties, using the real solar spectrum.