The sculpture titled Helios, created by UK artist Luke Jerram, will be on display in the Corn Exchange for ten days starting from Saturday, March 28.
The globe is an impressive seven metres in diameter and represents the sun on a scale of approximately 1:200 million.
It blends solar imagery with animated lighting and is accompanied by a surround-sound composition by Duncan Speakman and Sarah Anderson for a fully immersive experience.
Access to the installation, presented in partnership with Dorchester Town Council, will be free.
There will also be a special relaxed viewing session on the morning of Monday, March 30.
Visitors will also be able to view a separate exhibition featuring sun-themed artworks from the Dorset community and take part in creative activities including writing, movement, drawing and music, all centred on the theme of the sun.
Thousands of visitors are expected to come to see Helios, following the popularity of previous exhibits Museum of the Moon and Mars.
The project has been co-commissioned by the National Trust, Cork Midsummer Festival, Liverpool Cathedral, Old Royal Naval College and University College London.