High precision data from the archive of the TESS space mission are used as the basis of a study of the photometric variability of two young analogs of the Sun with planetary systems: the stars HD 63433 (TOI 1726), a member of the Ursa Major moving group of stars with an age of 414 million years and TOI 451 (CD-38 1467) from the Pisces-Eridani star stream (Psc-Eri) with an age of 120 million years. Manifestations of the activity of these stars with planetary systems are studied. Based on all the available observations we have estimated the rotational periods of the stars and the amplitudes of their brightness variability. The standard method has also been used to estimate the spottedness parameter A in an absolute measure. The areas of the spots on the surfaces of HD 63433 and TOI 451 greatly exceed the area of the spots on the Sun, 24500 m.s.h. and 12600-33200 m.s.h., respectively. The activity cycles of TOI 451 were estimated using data from the archive of the All Sky Automated Survey and indicated possible activity cycles of 125 and 1280 days. The data for HD 63433 suggest the existence of long-term changes in brightness, but are insufficient for quantitative estimates.

来自 TESS 太空任务档案的高精度数据被用作研究太阳与行星系统的两个年轻类似物的光度变异性的基础：恒星 HD 63433 (TOI 1726)，大熊座成员移动年龄为 4.14 亿年的恒星群和来自双鱼座-波江座星流 (Psc-Eri) 的年龄为 1.2 亿年的 TOI 451 (CD-38 1467)。研究了这些恒星在行星系统中的活动表现。基于所有可用的观测，我们估计了恒星的自转周期及其亮度变化的幅度。标准方法也已用于以绝对测量方式估计斑点参数 A。HD 63433和TOI 451表面斑点面积大大超过太阳表面斑点面积24500 msh 和 12600-33200 msh，分别。TOI 451 的活动周期是使用全天自动调查档案中的数据估算的，并指出可能的活动周期为 125 天和 1280 天。HD 63433 的数据表明亮度存在长期变化，但不足以进行定量估计。