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We imaged two starless molecular cloud cores, TUKH083 and TUKH122, in theOrion A giant molecular cloud in the CCS and ammonia (NH$_3$) emission with theVery Large Array. TUKH122 contains one NH$_3$ core "TUKH122-n," which iselongated and has a smooth oval boundary. Where observed, the CCS emissionsurrounds the NH$_3$ core. This configuration resembles that of the N$_2$H$^+$and CCS distribution in the Taurus starless core L1544, a well-studied exampleof a dense prestellar core exhibiting infall motions. The linewidth ofTUKH122-n is narrow (0.20 km s$^{-1}$) in the NH$_3$ emission line andtherefore dominated by thermal motions. The smooth oval shape of the coreboundary and narrow linewidth in NH$_3$ seem to imply that TUKH122-n isdynamically relaxed and quiescent. TUKH122-n is similar to L1544 in the kinetictemperature (10 K), linear size (0.03 pc), and virial mass ($\sim$ 2$M_{\odot}$). Our results strongly suggest that TUKH122-n is on the verge ofstar formation. TUKH122-n is embedded in the 0.2 pc massive (virial mass $\sim$30 $M_{\odot}$) turbulent parent core, while the L1544 NH$_3$ core is embeddedin the 0.2 pc less-massive (virial mass $\sim$ 10 $M_{\odot}$) thermal parentcore. TUKH083 shows complicated distribution in NH$_3$, but was not detected inCCS. The CCS emission toward TUKH083 appears to be extended, and is resolvedout in our interferometric observations.

Thermal Starless Ammonia Core Surrounded by CCS in the Orion A Cloud