See all three of SpaceX's history-making rockets together in one room

After recent successes, SpaceX is going to need a bigger trophy room. So far, the private spaceflight company has safely landed a total of three rockets after launching them into space.

Following a successful landing of the first stage of a Falcon 9 at Landing Zone 1 in Cape Canaveral on December 22, the company outdid itself by landing two more first stages on the "Of Course I Still Love You" drone ship at sea. It nailed the ocean landing first on April 8 and then again on May 6 under even more difficult conditions.

The three successful landings bring SpaceX closer to achieving its goal of reusing rockets, which could potentially cut the cost of spaceflight by millions of dollars.

And now, as CEO Elon Musk joked in a recent tweet, the company is running out of storage space.

The most recently recovered Falcon 9 first stage, which survived an even hotter and faster reentry into Earth's atmosphere than its two siblings, was just transported to SpaceX's hangar 39A at Cape Canaveral in Florida on Sunday to join the company's two other recovered rockets. The 12-story-long rocket made the journey on the back of a gigantic truck.

The next step is for SpaceX to prove that it can successfully refurbish reusable rockets for future flights.

SpaceX has already said that it doesn't plan on relaunching the first Falcon 9 it successfully landed. Instead, SpaceX plans to display it at their headquarters in Hawthorne, California, following inspection.

Musk recently tweeted that the most recent rocket took too much damage during reentry to be relaunched, so instead that rocket will be used for ground tests.

That leaves us with the rocket from the first barge landing on April 8. Musk has announced that we can expect to see SpaceX reuse this rocket as early as May or June.

Here's a photo of SpaceX's three prized rockets cozying up in hangar 39A:

SpaceX's goal is to make almost all of its Falcon 9 rockets reusable, which would dramatically reduce the cost of spaceflight. A Falcon 9 might fly as many as 100 times before retirement, Musk told Ars Technica in April.