The 210 degrees longitude line in Antarctica runs through the Eastern Hemisphere, passing through East Antarctica.

Here's why:

* Longitude lines run from North to South, marking distances east or west of the Prime Meridian (0 degrees longitude).

* Antarctica is situated in the Southern Hemisphere and is roughly centered around the South Pole.

* East Antarctica is the portion of the continent that lies to the east of the Queen Maud Land region.

Therefore, the 210 degrees longitude line falls within the Eastern Hemisphere and runs through East Antarctica.