Abstract DGP2026-46

Design of a Baffle System for VERITAS VEM QM Laboratory Measurements

S. M. Patwardhan (1), Y. M. Rosas Ortiz (1), S. P. Garland (1), N. Müller (1, 2), G. Alemanno (1), A. Maturilli (1), S. Adeli (1), A. C. Plesa (1), T. Hagelschuer (1), M. Pertenais (1), G. Peter (1)

(1) German Aerospace Center (DLR e.V.), Institute of Space Research, Berlin, Germany (2) Freie Universität, Berlin, Germany

The Venus Emissivity Mapper (VEM) is a multispectral push broom imager developed for the NASA Venus Emissivity, Radio science, InSAR, Topography, And Spectroscopy (VERITAS) mission and the ESA EnVision mission [1]. The main aim of VEM is to determine the surface emissivity of Venus [2], in order to distinguish basaltic from felsic regions. The instrument consists of an electronics box holding the control unit and power supply, an optics barrel with lenses and filters, an FPA with a detector, a turn-window unit, and a baffle unit [1].

The baffle unit consists of a two-stage assembly mounted in front of the turn-window unit. The first stage consists of an inner, multi-vane baffle cone designed to suppress potential stray light entering the VEM optical system. The second stage is a baffle shield mounted on top of the baffle cone, which interfaces with the spacecraft which prevents high temperatures on the baffle cone caused by direct sun illumination. The main function of the baffle is to protect the instrument’s optical system from stray light.

This system has been developed for the instrument when used in space, however we need to develop a system serving similar purposes for use during lab measurements with the VEM Qualification Model (QM). The goal of these measurements is to demonstrate VEM’s capability to distinguish rocks of basaltic and felsic composition through measurements of Venus analogue rock samples at Venus surface temperatures using the emissivity chamber at the Planetary Spectroscopy Laboratory, DLR Berlin [5]. In order to perform these measurements a new baffle for the VEM instrument must be constructed to fit the geometry and requirements of the emissivity chamber. The baffle system will be tested prior to VEM QM measurements using an emulator of the VEM instrument [3,4]. This contribution will detail the design considerations for the baffle and for the laboratory measurement campaign with the VEM QM.

[1] T. Hagelschuer et. al., SPIE, Oct. 2024, doi: 10.1117/12.3028082.

[2] S. E. Smrekar et al., 2022 IEEE AERO, Mar. 2022, doi: 10.1109/AERO53065.2022.9843269

[3] S. Garland et al., SPIE, Oct. 2024, p. 18. doi: 10.1117/12.3028083.

[4] S. Garland et al., SPIE, Aug. 2025, doi: 10.1117/12.3064430.

[5] A. Maturilli, et al., LPSC, Mar. 2023, no. 2806, 2023.