Julius Caesar discussion

In act 2 scene 1 the following exchange takes place:

DECIUS BRUTUS
Here lies the east: doth not the day break here?
CASCA
No.
CINNA
O, pardon, sir, it doth; and yon gray lines
That fret the clouds are messengers of day.
CASCA
You shall confess that you are both deceived.
Here, as I point my sword, the sun arises,
Which is a great way growing on the south,
Weighing the youthful season of the year.
Some two months hence up higher toward the north
He first presents his fire; and the high east
Stands, as the Capitol, directly here.

What is the point of this interaction??

I haven't read this since almost two years ago, so this interpretation may be completely wrong. But I'll go for it: They are discussing how the sun has many facets in its effects on the different parts of the earth despite where it rises from. The purpose of saying this is that their lofty Capitol is the symbolic "east" of where the sun has most strength.

I'm pretty sure Shakespeare just wanted some characters to speak so that it gives the audience the illusion that Brutus and Cassius are whispering, otherwise they'd be whispering for two minutes while it looks like the others are just listening in.

Good point, that must be it.. Thanks guys