Description: This dataset contains measurements from the HEARER radiospectrometer aboard the Suomi 100 satellite acquired during the EISCAT heating campaign on December 8–9, 2020 (UTC). This version adds two passes from December 8 (morning and evening) and updates the December 9 file with an expanded time range. Files in this version Data_SUOMI100_satellite_HEARER_instrument_Day20201208_morning.txt Data_SUOMI100_satellite_HEARER_instrument_Day20201208_evening.txt Data_SUOMI100_satellite_HEARER_instrument_Day20201209_morning.txt (expanded range: sample indices 250000–350000) Metadata (also included inside each file) Spacecraft: Suomi 100 (COSPAR ID 2018-099AY) Instrument: HEARER Instrument type: Radio spectrometer Measurement dates: December 8–9, 2020 (UTC) Data rate: Approximately 1000 samples per second. The dataset includes gaps. Data format: Column 1: sample index (integer) Column 2: observation (integer) Prepared by: Esa Kallio (esa.kallio@aalto.fi), Aalto University, Finland Preparation dates: original files prepared Sep 8, 2022; updated for this version on Mar 21, 2026. Changelog (since v1.0, 2022‑09‑08) Added two new files from 2020‑12‑08 (morning and evening passes). Replaced the 2020‑12‑09 file with a wider time range (sample indices 250000–350000; previously 280000–319999). Updated title and metadata accordingly. Related publications Kallio et al. (2022), “Radar – CubeSat Transionospheric HF Propagation Observations: Suomi 100 – Satellite and EISCAT HF Facility”, Radio Science. Peitso et al. (2026), “Ionospheric Effects on Transionospheric HF Propagation During the Joint Suomi 100 CubeSat–EISCAT Heating Campaign”, submitted.