spiral arm tracer meaning in English
示臂天体
Examples
- Spiral arm tracer
示臂天体 - Interstellar hydrogen will emit a characteristic wave with wavelength 21cm . most of the sources of this wave are gas clouds in the spiral arms . second to the 21cm emission , the radio wave emitted by the molecular gas clouds in the arms are also good spiral arm tracers
在旋臂中的氢气分子云，会发射出波长为21厘米的无线电波，只要探测这些无线电波在天空中的强度分布，便可推算出旋臂的结构。