What is the purpose of the poet’s use of the phrase “learn’d astronomer” in line 1 of the poem

There could be several reasons but having seen the poem would provide a clearer answer.

Explanation:

They could use this phrase as an attempt of creating a concise understanding that the astronomer was qualified or learn'd from. It could be a use of imager or even personification. If the poem was posted, I would be able to answer it better.

a) the british government verbally threatens the colonies.

b) the british government has sent navies and armies to the colonies.

c) the british government argues against separation in the house of commons.

d) the british government has sent petitions and letters to all of the colonists.