What was the organization in charge of astronomy in Han Dynasty?

Problem description:

This is an institution similar to Qin, but it is definitely not it. Besides, does it belong to a surname?

Analysis:

There were Taishi Gong and Taishi Order in the Western Han Dynasty. There was only Taishiling in the Eastern Han Dynasty. This is not only an official name, but also an institution name. Its main functions are observing the sky, making calendars, waiting for the weather and adjusting the clock rhythm.

Taishi Museum is an astronomical institution established in Wei, Jin, Southern and Northern Dynasties.