Parent volatiles in Comet 103P/Hartley 2 observed by Keck II with NIRSPEC during the 2010 apparition

► We conducted near-infrared high-dispersion spectroscopic monitoring observations of comet Hartley 2 by Keck2 with NIRSPEC in 2010. ► We detected 7 parent volatiles and their mixing ratios (relative to H2O) were consistent on different dates. ► Spatial profiles of parent volatiles along the slit were sometimes asymmetric (probably, attributed to jets or icy grains as distributed source). ► Parent volatiles might be segregated into two distinct phases (one is enriched in CH3OH and H2O while another is enriched in C2H6, C2H2, and HCN). ► Ortho-to-para abundance ratio of water is consistent with the results ever obtained.