The world is entering an exciting new Space Age. Where once the superpowers competed in a space race to the moon, today commercial companies like SpaceX, Virgin Galactic and Blue Origin are finding new business models to finally realize the economic value of space.

As private companies dominate the economic market for low-earth orbit, the government is rightfully looking to the moon and beyond. New ambitious missions are being planned today to send larger probes beyond the confine of our solar system, all the way to interstellar regions — all of which will provide us with unprecedented knowledge about our universe and worlds to explore.

However, while these missions hold great promises and will prove transformative, we unfortunately lack the adequate deep-space propulsion capacity capable of carrying equipment and people reliably to the moon, to Mars and beyond.

Everyone is still using the propulsion technology developed by NASA in the first Space Age, when chemical rockets sent NASA astronauts to the moon over five decades ago.

Relying on today's propulsion technologies will result in long duration missions with significant unsafe exposure for humans to cosmic radiation and microgravity; combined with infrequent travel windows, difficult abort scenarios and limited reusability. Even in the case of scientific probes, the limitations are severe: reaching the confines of our solar system is at best done as "one-shot" flyby missions, which take years or even decades of nail-biting travel time to get there. In short, today's propulsion technologies and near-term concepts make for a risky and expensive endeavor to explore and develop our solar system and access its vast resources.

Fortunately, there is a realistic option just over the horizon: fusion power. Once harnessed, it will prove to be the key that can fulfill the promise of spaceflight. It achieves faster travel times, allows exploration and transport further than any other technology, produces less and cleaner waste and is highly reusable.

Fusion for energy is of great interest to many nations already: China has made serious investments in its own fusion reactor effort, closely followed by the U.K. Here in the U.S., Congress and the Department of Energy are agreeing on ambitious timelines for government research while private companies, funded by venture capital and industry consortia, are rapidly moving toward development of a power plant.

However, while fusion is the clear answer to sustainable space flight, there are no programs in the U.S. designed to leverage the capabilities being developed for on-earth fusion power. Put simply: Fusion propulsion is neither on the military's nor NASA's technology road maps, and the Department of Energy supports fusion energy research, but devotes nothing toward space propulsion yet. It appears that the space stakeholders are waiting to see it develop on earth first before considering it for space.

This is a mistake with huge consequences. Pushing a spaceship forward, which "simply" requires thrust generation, may be achievable earlier than sustainable large-scale electricity generating power-plants on Earth. The infrastructure work of adapting the latest discoveries in fusion and plasma science to space applications needs to start now. It will bear unquantifiable fruits soon.

In October, the heads of NASA and the DOE announced a memorandum of understanding meant to expand cooperation between the two agencies on space, focusing on space nuclear power, science and engineering. This follows the DOE being added as a member of the National Space Council in February.

Within this new interagency collaboration, there is great promise for cooperation on fusion propulsion. ARPA-E, the semi-independent "Advanced Research Projects Agency — Energy," advances high-potential, high-impact energy technologies, to prime the way for the private-sector to lead. ARPA-E has already advanced fusion programs.

Now, it is time to think of an "ARPA-S(pace)" like program. Whether as a funding subset within ARPA-E, or at NASA. It would build upon the excitement around space travel to create new private-public investment opportunities into fusion propulsion, so that America can once again lead the new Space Age.

Faster, further, safer, less wasteful space-propulsion engines and scalable space-based power-supplying technologies are very possible and should be in humanity's sustainable future, and soon. The only question is: Are we going to be the leaders in this exciting arena or will we need to buy those technologies from abroad?

Andrew Holland is the executive director of the Fusion Industry Association. Stephane Lintner is the acting CEO of the HelicitySpace Corporation, CEO of Jiko Bank, a former managing director at Goldman Sachs, and a Caltech Ph.D. alumni (e-mail: stephane.lintner@helicityspace.com). They wrote this article for the Baltimore Sun.