Preparatory Lab Experiments for the Upcoming Rocket Lab Mission as Part of the Morning Star Missions to Venus
KEVIN JANSEN, Sara Seager, Janusz Petkowski, Christopher Carr, Darrel Baumgardner, Margaret Tolbert, Weston Buchanan, Iaroslav Iakubivskyi, Steven Benner, Jingcheng Huang, Massachusetts Institute of Technology
Abstract Number: 576
Working Group: Planetary Aerosols: From Earth to Exoplanets
Abstract
Interest in Venus has recently been reignited following the controversial detection of phosphine in the Venus atmosphere, a potential indicator for life. Following this renewed interest, the Morning Star Missions, a series of astrobiology-focused missions to Venus, have been planned to probe Venus clouds. The mission aims to determine if the clouds are either capable of supporting microbial life, or contain signs of organic species despite Venus clouds containing high concentrations of sulfuric acid (>70% by mass). The upcoming Rocket Lab Mission to Venus, the first part of the Morning Star series of missions and the first primarily privately-funded small and low-cost mission to another planet, is set to launch in early 2025. This preliminary mission will send a single, newly developed instrument called the Autofluorescence Nephelometer (AFN) with the aim of characterizing the asphericity and refractive indices (RI) of cloud particles, as well as detecting potential organic compounds through fluorescence. The AFN directs a 440 nm laser onto cloud particles through a pressure vessel window and subsequently measures both polarized, backscattered light and fluoresced light from the particles. To understand and calibrate the expected data retrieved from the upcoming mission, a series of laboratory prototype AFNs have been developed and tested using materials with known RI and fluorescence properties, along with organic/concentrated sulfuric acid mixtures to mimic possible Venus cloud particles. Using the prototype AFN, we have successfully observed changes in fluorescence using particles with varying concentrations of fluorescein, a fluorescent dye, as well as aged formaldehyde/sulfuric acid mixtures. In addition, polarized scattering measurements have been able to detect changes in RI and particle asphericity, paving the way for RI retrievals. Overall these preliminary AFN laboratory experiments show great potential for cloud particle detection in the upcoming Rocket Lab Mission to Venus, as well for experiments on Earth.