The success of the  Payload Preliminary Design Review of the  ESA Ariel in 2023 constitute for Ariel a new step. The selection of the industrial partner in charge of the satellite (Airbus Industrie) has launched the discussions on the interface payload/satellite. The construction of the instrument is progressing, with first models already in tests and the arrival of the detectors. A review of the Ariel mission and the AIRS instrument managed by France will be done during the Ariel day  on January 18, 2024.

Following the pattern of the annual Ariel France days held in 2021, 2022  and 2023, this new day should allow the whole French community to get involved in the mission, which includes in particular an opening to the international community in "open science". The insertion of Ariel in collaborations with other ground or space instruments is an important element to prepare the optimal scientific return.

We therefore invite researchers or PhD students to participate in this day, and to propose oral contributions on the various aspects, theoretical, observational or programmatic in relation to Ariel. This day will be held in a hybrid mode, with face-to-face sessions at IAP and remote connections.

Invited presentations will describe the progress of the mission, both technically and in terms of modeling. Contributions of 10 minutes are solicited, before the January 16 deadline.