中性氢21厘米谱线,中性氢21厘米谱线,zhongxingqing 21 limi puxian,zhongxingqing,limi,puxian,[拼音]:zhongxingqing 21 limi puxian[外文]:celestial 21 cm-hydrogen line氢原子在它的基态,有两个超精细结构子能级。星际物质中处于...