Venusian Neutrals Analyser (VNA) for the ISRO Venus Orbiter

Following the recent selection of three Venusian missions by NASA and ESA, Venus has become a key target for planetary research in the coming decade.

The Swedish Institute of Space Physics (IRF) was the Principal Investigator of the plasma package on ESA’s Venus Express mission. Scientists at the IRF are among the most active in Europe in the field of Venus–solar wind interaction.

IRF now has a unique chance to further contribute to advances in Venus research by participating in the Indian Space Research Organisation’s (ISRO) Venus Orbiter mission (launch in 2025).

Through this proposal, we apply for funding to cover the components, external services, and travel to India requisite for manufacturing and delivering a Swedish instrument, the Venusian Neutral Analyser (VNA), to ISRO’s Venus Orbiter mission.The VNA is a lightweight, low-power but highly capable energetic neutral atom (ENA) analyzer.

With the VNA measurements, we aim to better understand the dynamics of the induced magnetosphere of Venus. The plasma in the induced magnetosphere is highly dynamic and responds to variations in the solar wind. We will also investigate how the Venusian induced magnetosphere, ionosphere, and thermosphere couple.

The physics of the coupling is the missing information to understanding how the atmospheric content is energized and eventually escapes to space.

These questions are remained to be answered after the successful Venus Express/ASPERA-4 experiment, in which the Swedish space community has exploited data for more than 15-years. The VNA has the following stand-alone science questions: 1. How does the global plasma environment of Venus respond to solar wind variations? 2.

How do the Venusian induced magnetosphere, ionosphere, and thermosphere couple?To answer these questions, the VNA will pursue the following science objectives: 1a. Investigate the global dynamics using the innovative ENA imaging technique. 2a.

Establish the impact of the contribution of particle precipitation on the mass and energy balance in the upper atmosphere.The VNA will use the ENA imaging technique to address these science objectives. The VNA has already been selected by the ISRO to be part of its Venus mission.

The VNA will be developed by the IRF, Kiruna, and integrated into the plasma package, Venus Ionospheric and Solar Wind particle AnalySer (VISWAS), provided by the Space Physics Laboratory (SPL) in Trivandrum, India.

The VNA sensor will be a replica of the SCIENA instrument developed at the IRF for ESA’s Comet Interceptor, already funded by SNSA and ESA, in addition to the internal IRF contribution.Through this proposal, we apply for funding to cover certain costs during the implementation phase (2023–2024) up to the delivery of the VNA.

The deliveries of the engineering models of the VNA (two sets) in mid-2023, the proto-flight model of the VNA in mid-2024, and the flight model of the VISWAS at the end of 2024 are the relevant milestones of this project. The main tasks are to manufacture, validate, calibrate, and deliver the required VNA models.

We are applying the costs for the components, external services, and travel to India. All the personnel costs are covered by the IRF.

The IRF will also conduct the requisite science preparations, the development of the ground segment for operation and data processing, and the data archiving, which will also be covered by the IRF.