In this letter, we report initial experimental results which provide the foundation for low-terahertz (low-THz) radar imagery for outdoor unstructured scenarios as expected in automotive sensing. The requirements and specifications for a low-THz single imaging radar sensor are briefly outlined. The imaging capabilities of frequency-modulated continuous-wave (FMCW) radar operating at 150 GHz are discussed. A comparison of experimental images of on-road and off- road scenarios made by a 150-GHz FMCW radar and a reference 30-GHz stepped-frequency radar is implemented, and their performance is analyzed.