Nearly half of the Discovery Centre's construction costs will be covered by government funding when it moves into its new home on the Halifax waterfront.​

Nova Scotia Premier Stephen McNeil and Conservative MP Peter MacKay were on hand to make the announcement on Monday.

The new $18.5-million science museum will be built in the Nova Scotia Power building on Lower Water Street. The Nova Scotia government is contributing $6 million and the federal government is kicking in $3 million.

The Discovery Centre will be responsible for the remaining cost and will also cover any cost overruns on the construction.

"It's an unbelievable day. It's wonderful news — a great way to start off 2014," said Dov Bercovici, the president and CEO of the Discovery Centre.

The centre currently leases space on Barrington Street. When it moves into its new digs, it will not have to pay rent —​ Emera, the parent company of Nova Scotia Power, is contributing the space rent-free for at least 25 years.

The new centre, which will be double in size to approximately 40,000 square feet, will feature an interactive planetarium that makes people feel as though they are travelling in space.

"It's similar to a planetarium but it's a completely immersive experience," said Bercovici.

"We are going to immerse people in experiences like being under the ocean as if you were a fish, being in the cosmos, flying through the cosmos and going from our solar system to the Orion Nebula."

Nathan Gray, the 10-year-old Nova Scotia boy who is the youngest person in the world to discover a supernova, said he's excited about the new Discovery Centre. (CBC)

Nathan Gray, the 10-year-old Nova Scotia boy who is the youngest person in the world to discover a supernova, said he's also excited about a touch tank with live sea creatures.

"It's usually, 'Don't touch because you can break it easily.' So it's going to be good," he said.

Travelling exhibitions will be brought to Nova Scotia with donations from corporations such as Wilsons Fuel and Medavie Blue Cross.

The new Discovery Centre is expected to be finished toward the end of 2015.

"At the moment we have all of the design development plans done. We go next to construction drawings and then to tenders and it's about a two-year process," said Bercovici.