ITU-FAA-SSDTL is designing and developing the first 6U CubeSat to house the Rubidium Atomic Frequency Standard (RAFS) based atomic clock prepared by TUBITAK-UME for the Turkish Space Agency (TUA). The TUA project aims to test RAFS in low earth orbit towards (LEO) use in national GNSS satellites. The CubeSat is planned to be launched into LEO by early 2026. The project, which is handled by ITUNOVA TTO and in PDR stage, has started in mid-2023. The main design challenges are thermal protection and control of RAFS payload (already managed by SSDTL) and its reference signal transmission which is handled by ITU-RF Lab. RAFS CubeSat EQM and FM units will be readied and tested during 2025 in ITU-FAA-SSDTL.