Basedon the diurnal appearant motion of heavenly body and the better conditions of celestial fixing,this paper analyses the observation opportunity in several kinds of fixing,give the model of ob- servation and the method of observation opportunity.

The progress of research on in-situ observation technique for crystal growth in resent years is reviewed.

Selection on degasification temperature and observation time of radon observation sample;

To solve the contradiction between target tracking accuracy and observation interval,an algorithm of calculating observation time based on target estimate covariance control was presented.

Experiment study on the variation of water mercury content with observing time and its relation with observing environment;

The experiment of time sequence observation of laser orientation angel for transmitting laser beam through an optical element under heating of powerful laser has been carried out.