In 1975, Yasuho Yamashita noted that some higher temperature carbon stars displayed the typical spectral characteristics of a CH star, but did not have the same kinematic properties. That is, they did not have the higher space velocities characteristic of the older stellar population.
Yasuho Yamashita's 1975 study revealed that some higher temperature carbon stars exhibited the usual spectral features of a CH star, yet lacked the same level of space velocity characteristic of the older stellar population.