In this contribution, we present the status and first data from the Radio Detector (RD) at the Pierre Auger Observatory, consisting of 1660 radio antennas deployed across the 3000 km² surface detector array. These antennas measure the radio emission from extensive air showers in the 30−80 MHz band, enabling electromagnetic energy measurements for air showers with zenith angles above 65∘. Combined with the muonic measurements from the water-Cherenkov detectors (WCDs), this allows mass composition studies at the highest energies. The large-scale deployment of the RD began in November 2023 and was completed in November 2024. A full end-to-end calibration shows consistency between Galactic and in-lab calibration to better than 5% and includes continuous monitoring for hardware failures, ensuring, for example, antenna alignment within 5∘. We present the first data, demonstrating a strong correlation between the electromagnetic energy measured by the RD and the total shower energy measured by the WCD, confirming that the detector chain - including triggering, data readout, absolute calibration, and reconstruction is well understood. We highlight a particularly impressive 32 EeV shower at a zenith angle of 85∘, producing a 50 km-long radio footprint, showcasing the unique capabilities of this detector.
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