Overview
- The COMPASS team using ALMA reported the first secure interstellar detection of fully deuterated methanol (CD3OD) on Wednesday, October 7, 2026, identifying ten clear spectral lines toward protostar IRAS4A2 in the Perseus cloud.
- Measured abundances place CD3OD at about 0.04 percent of ordinary methanol while singly deuterated forms show roughly 1 percent D/H and multiply deuterated variants reach near or above 10 percent.
- Current astrochemical models fail to reproduce this non‑statistical pattern and in some cases underpredict the CD3OD abundance by up to five orders of magnitude, indicating a missing formation process on cold ice-coated dust grains.
- The ALMA spectra include additional unidentified lines that likely belong to other multiply deuterated methanol isotopologues and labs at MPE have begun targeted spectroscopy to provide the reference data needed for firm identifications.
- COMPASS also found surprisingly frequent methanol maser signals in more than half of the surveyed young stars, a result that together with the deuteration pattern will reshape lab experiments and chemical networks used to trace how prebiotic molecules form and enter planet-forming disks.