ぴかぴか光る[pikapikahikaru] to sparkle
旭光[kyokkou] rays of the rising sun
威光[ikou] power
稲光[inabikari] (flash of) lightning
曳光弾[eikoudan] tracer bullet

栄光[eikou] glory
円光[enkou] halo
炎光[enkou] flame
黄道光[koudoukou] zodiacal light
可視光線[kashikousen] visible ray

観測[kansoku] observation
観測ヘリコプター[kansokuherikoputaa] observation helicopter
計測[keisoku] measurement
再測量[saisokuryou] resurvey
三角測量[sankakusokuryou] triangulation

実測[jissoku] survey
実測図[jissokuzu] measured map
写真測量[shashinsokuryou] photographic surveying
推測[suisoku] guess
測候所[sokkoujo] weather measurement station