节气

var now = new Date();
var SY = now.getYear(); 
var SM = now.getMonth();
var SD = now.getDate();var sTermInfo = new Array(0,21208,42467,63836,85337,107014,128867,150921,173149,195551,218072,240693,263343,285989,308563,331033,353350,375494,397447,419210,440795,462224,483532,504758)
var solarTerm = new Array("小寒","大寒","立春","雨水","惊蛰","春分","清明","谷雨","立夏","小满","芒种","夏至","小暑","大暑","立秋","处暑","白露","秋分","寒露","霜降","立冬","小雪","大雪","冬至")
tmp1 = new Date((31556925974.7*(SY-1900)+sTermInfo[SM*2+1]*60000)+Date.UTC(1900,0,6,2,5))
tmp2 = tmp1.getUTCDate()
if (tmp2==SD) solarTerms = solarTerm[SM*2+1]
tmp2= tmp1.getUTCDate()
if (tmp2==SD) solarTerms = solarTerm[SM*2] solarTerms 就是最后得到节气的值 现在这段代码能实现把节气显示出来了。但是我想实现显示一个时间段的节气。 就是2007-08-01 到 2007-08-23 是大暑  2007-08-23 到 2008-09-12 是 秋分  这样的功能 
请问该怎么改那？