SpaceX's valuation has risen steadily as the company has raised funding for rockets, spacecraft and more over the past decade. Most recently, SpaceX was reportedly valued at $30.5 billion. The company has been able to draw investment from private markets with ease, as a person familiar with SpaceX's fundraising this year said both its equity raises were oversubscribed. In the most recent round, investor demand meant SpaceX could have raised between $300 million to $400 million more than it did, the person said.

Additionally, Musk's space company is now more valuable than his electric vehicle company. Tesla shares closed down on Friday giving the company a market value of $32.8 billion – just below SpaceX's valuation.

The value of SpaceX has risen to $33.3 billion, people familiar with the company's recent fundraising told CNBC. In an amendment of its April fundraising effort, a filing last week from SpaceX showed the company's latest round brought in $536 million at a price of $204 a share. SpaceX has raised just over $1 billion this year, as the company accelerates fundraising to develop its plan to beam high-speed internet to anywhere on Earth.

Tesla, on the other hand, has lost more than half its value since August. Shares of Tesla are down more than 43% this year, steadily dropping. The electric automaker faces slowing demand, increasing costs from the U.S. trade war with China and doubt from Wall Street about its financial health. Only a week after Musk deferred on questions about the company raising capital, Tesla raised $2.7 billion in a stock and bond offering. While he has said Tesla will end 2019 with a record number of vehicles delivered, analysts warn that deliveries will be lower than he forecast, especially in key markets such as China.

The space company has undertaken two ambitious and capital intensive projects: The building of a network of nearly 12,000 internet satellites, called Starlink, and the development of a rocket big enough to send 100 people to Mars, called Starship. Earlier this year, Musk said SpaceX "has to be incredibly spartan with expenditures" due to the projects. But the company's financial standing appears stable.

Musk told reporters this month that SpaceX has "sufficient capital" to get its Starlink satellite network "to an operational level." Musk believes SpaceX will be the key to funding his vision of colonizing Mars, as he estimates Starlink could generate at least 10 times the revenue that the company's business of launching rockets could. While SpaceX's annual launch revenue is estimated at about $2 billion, Musk sees that topping out at $3 billion in the coming years. But Starlink he said could bring in revenue of "more like $30 billion a year."

"Total internet connectivity revenue in the world is about $1 trillion and we think maybe we can access about 3%" with Starlink, Musk said.