What is the 42 solar terms?

I've only heard of the 24 solar terms.

24 solar terms is: beginning of spring, rainy, startled, vernal equinox, Qingming, Grain Rain, Changxia, Xiaoman, Mangzhong, Summer Solstice, Slight Summer, beginning of autumn, Early Summer, White Dew, Autumn Equinox, Cold Dew, Early Frost, beginning of winter, Light Snow, Heavy Snow, Winter Solstice, Slight Cold and Severe Cold. Each solar term is about half a month apart and divided into twelve months. The beginning of the month is called the solar term, and the middle of the month is called "Zhongqi".

There is also a 24 solar term song:

The spring rain shocks the spring and the valley, and the summer is full of mountains and summer heat.