As investors in public equities, we're sometimes deprived of access to some of the best businesses on the planet. I'd love to own shares in In-N-Out Burger, for example. Others clamor for access to Twitter and Pinterest.

Of them all, I'm most interested in SpaceX. Founded in 2002 by Elon Musk, a year before he helped birth Tesla Motors (NASDAQ:TSLA), SpaceX is a moniker, short for Space Exploration Technologies.

Like Tesla, SpaceX is a vertically integrated company that handles design and production in-house. And with good results: the company's Dragon unmanned vehicle docked with the International Space Station during a historic resupply mission in October. A second mission lifts off Friday.

All told, SpaceX is signed on for 12 resupply missions to the ISS. More than 40 missions are on the books between now and 2017, according to the company's launch manifest. That's a huge backlog and likely to be troubling for the United Launch Alliance of Boeing (NYSE:BA) and Lockheed Martin (NYSE:LMT), both of which have had a tougher time generating revenue from space missions in recent years.

Lockheed's Space Systems revenue improved 1.2% last year but remains down from 2010 levels. Boeing has suffered five straight years of declining revenue from space and defense contracts. SpaceX, the disruptor, has to be at least partially responsible for the decline.

At the very least, I find it telling that millionaire Dennis Tito, the first space tourist in American history, has outlined plans for a 501-day privately funded mission to Mars using SpaceX's Falcon Heavy launch rocket combined with a Dragon spacecraft.

So why not go public? To be sure, Musk has his hands full with Tesla and ramping production for the Model S sedan while battling The New York Times. Taking SpaceX public now would create added pressure at an inopportune time.

So be it. The competitive dynamics favor SpaceX about as much as they ever have, which improves the odds of a successful IPO. I'd love to see it, but you may have a different view. Please weigh in using the comments box below.