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We report direct evidence for asymmetry in the early phases of SN 1987A viaoptical spectroscopy of five fields of its light echo system. The light echoesallow the first few hundred days of the explosion to be reobserved, withdifferent position angles providing different viewing angles to the supernova.Light echo spectroscopy therefore allows a direct spectroscopic comparison oflight originating from different regions of the photosphere during the earlyphases of SN 1987A. Gemini multi-object spectroscopy of the light echo fieldsshows fine-structure in the H-alpha line as a smooth function of position angleon the near-circular light echo rings. H-alpha profiles originating from thenorthern hemisphere of SN 1987A show an excess in redshifted emission and ablue knee, while southern hemisphere profiles show an excess of blueshiftedH-alpha emission and a red knee. This fine-structure is reminiscent of the"Bochum event" originally observed for SN 1987A, but in an exaggerated form.Maximum deviation from symmetry in the H-alpha line is observed at positionangles 16 and 186 degrees, consistent with the major-axis of the expandingelongated ejecta. The asymmetry signature observed in the H-alpha line smoothlydiminishes as a function of viewing angle away from the poles of the elongatedejecta. We propose an asymmetric two-sided distribution of 56Ni most dominantin the southern far quadrant of SN 1987A as the most probable explanation ofthe observed light echo spectra. This is evidence that the asymmetry ofhigh-velocity 56Ni in the first few hundred days after explosion is correlatedto the geometry of the ejecta some 25 years later.

Asymmetry in the Outburst of SN 1987A Detected Using Light Echo Spectroscopy