A lot has changed at SpaceX in the last 18 months. The company has made resupply missions to the International Space Station seem routine, performed the first attempt to recover a rocket for reuse, and announced a $1 billion investment from Google that will help it develop more robust Internet connections for Earth and, eventually, human colonies elsewhere in the solar system. However, nothing has changed with plans for SpaceX stock, which will remain in private hands. Sorry, space enthusiasts.

Although we'll have to wait a bit longer for a SpaceX IPO, there are a dozen or so companies involved in Space Race 2.0. They may not get the hype of Musk's baby -- or have the technological prowess, whether real or perceived -- but the potential market for space supply and transport is large enough to support many successful players. Here are a few you can actually invest in.

Company

Spacecraft/Launch Vehicle

First Mission

First Manned Crew

Space X

Dragon/Falcon

May 22, 2012

late-2017 (latest expected date)

Orbital Sciences (OA) & Alliant (NYSE: ATK)*

Cygnus/Antares

September 18, 2013

Cargo only

Lockheed Martin (LMT -0.55%) & NASA

Orion/Space Launch System (NASA)

December 5, 2014

2021

Boeing (BA 0.39%) & Bigelow Aerospace

CST-100/Multiple**

Early 2017

Mid-2017

*Will merge into one company, Orbital ATK, on February 10, 2015. **Designed to be compatible with Atlas V, Delta IV, and Falcon 9 rockets. Sources: Company websites and disclosures.

Not all companies with space ambitions are created equally, however, and success has been difficult to come by for those targeting ISS resupply contracts. Let's survey the spacecraft first.

Beam me up?
Orbital Sciences is developing the Cygnus spacecraft under a cargo resupply contract with NASA. Although it will never ferry humans back and forth from the ISS, Cygnus will provide more flexible options for American space ambitions than relying on our Russian partners. While the biggest obstacle for Cygnus might be its launch vehicle Antares, merging with Alliant, a leader in rocket propulsion systems, will certainly provide a big boost. Will it be enough to match the costs expected to be achieved by SpaceX's Dragon/Falcon combination?

Long before it expected to merge with Orbital Sciences, Alliant actually designed a capsule named Liberty, but scrapped the project after it wasn't selected by the Commercial Crew Integrated Capability program at NASA. A longtime partner of national space programs sponsored by the United States, the company is working with NASA on the Orion/Space Launch System combo -- providing the launch abort motors for the Orion spacecraft and heat shield components. After the merger, Orbital ATK will be the only company in the new commercial space race with major, direct stakes in two spacecraft/launch vehicle combinations.  

Meanwhile, Lockheed Martin is going full-steam ahead developing the Orion spacecraft. While capable of resupplying the ISS, Orion is intended to allow humans to explore the Moon, asteroids, and eventually Mars. It would also figure to play a prominent role in NASA's proposed Mars practice run, which plans to establish a permanent human presence in the atmosphere of Venus in the next several decades. However, Orion isn't expected to conduct its first manned mission until at least 2021. That's nearly four years after the current deadline for a manned mission from SpaceX, although the deadlines for all companies in the table above have shifted in the last 18 months.

A view of the Earth, moon, and sun from space

Image source: Getty Images.

Not far behind is the CST-100 spacecraft from Boeing, which is designed to be rocket agnostic. In fact, the company is actually in the lead in terms of scheduled manned launch dates and funding received from NASA. It's also the only company not named SpaceX that was awarded a NASA contract to provide manned launches to the ISS. Yet, despite earning an identical contract with identical milestones, Boeing is eligible to receive up to $1.6 billion more than SpaceX.

It is rocket science
Let's face it: Falcon from SpaceX sits atop the leader board in nearly all launch categories including costs, reusability, and modernity. It's a big part of the reason you wish you could buy SpaceX stock. And although the company failed to land Falcon on a drone barge after it effortlessly dropped a Dragon capsule into orbit for another rendezvous with the ISS, you have to admit it was excitingly close.

Orbital Sciences lit up the night sky for a different, and much less fortunate, reason last October when its Antares rocket exploded on the launch pad. There were no casualties save the cargo-loaded Cygnus that was on its way to the ISS. While the launch failure postponed the shareholder vote on whether to merge with Alliant, the merger willl proceed as expected. Just in case, Orbital Sciences signed a supply deal with Russia’s Energia to replace Antares’ first stage with newer, more powerful rocket engines. It’s a good near-term fix, but Alliant is widely expected to provide the critical long-term fix Antares needs.

Meanwhile, NASA has tapped Alliant to provide the solid rocket boosters for its Space Launch System, a family of launch vehicles that are the administration's long-awaited replacement to the Space Shuttle program. The rockets will do the dirty work for getting the Orion capsules into orbit and other destinations in the solar system and could also be used to launch commercial and exploratory satellites and probes.

Last but not least is United Launch Alliance, the joint venture of Lockheed Martin and Boeing that provides launch services on three launch vehicles: Delta II, Delta IV, and Atlas V. The company is also working on a new design that will succeed the Atlas V and, as widely expected, provide a little more competition to SpaceX. Investors are still awaiting an update from the company. 

Don't forget about Space Race risks
You may wish you had the opportunity to invest in SpaceX, but you probably aren't jealous about missing out on the risks involved, either. The company isn't shy about the fact that it's still proving its technology. In other words, it accepts a certain degree of failure as it figures things out. Could you imagine what would happen to SpaceX stock if it encountered a catastrophic failure for one of its launches? One failed launch may not even matter in the big picture, but Mr. Market isn't always so forgiving. Just ask Orbital Sciences. 

With that in mind, there are several viable alternatives to SpaceX stock since it won't be going public anytime soon. Just remember that development timelines are described in decades, deadlines are likely to move around, and the enormous expenses involved make lucrative government contracts key to floating programs until launches become more regular. After digesting all of that, you can sit back and enjoy the wild ride ahead.