Within the ever-popular Star Trek fictional universe, Starfleet is described as a uniformed space force maintained by the United Federation of Planets (“the Federation”) as the principal means for conducting deep space exploration, research, defense, peacekeeping and diplomacy.
Within that narrative, Starfleet began as an Earth agency not unlike NASA, dedicated to space exploration and eventually utilizing interstellar starships such as the Enterprise to travel the galaxy.
On Star Trek’s version of Earth, warp drive (the ability to warp space / travel faster than light) was invented and first flown in 2063 by hipster scientist Zefram Cochrane. It was Cochrane’s achievement that signaled to observing Vulcan spacefarers that Earth was ready for open extraterrestrial contact.
So much for science fiction.
United States Manned
Back in the real world, the United States has undeniably led the way in human penetration of space. American astronauts first landed on the moon in June 1969, and did it five more times through 1972. Since then, for mainly political and economic reasons, no human has returned to the moon — though that will likely change soon.
United States Unmanned
Meanwhile, U.S. unmanned craft have explored much of our solar system, including multiple landings on Mars; and two U.S. deep space probes, Voyager I and Voyager II, have officially left our solar system and entered interstellar space. Remarkably, 43 years after launching from Earth, both Voyagers are still sending back scientific data.
In fairness, the U.S. certainly isn’t the only nation to boldly go into space. In the early days of manned spacefaring, Russia (then the USSR) briefly took the lead, achieving the first successful launch of a human, Yuri Gagarin, to low earth orbit in 1961. In 1971 and 1973, Russia became the only nation besides the U.S. to successfully land probes on Mars. Starting in October 2000, Russian Soyuz rockets have safely carried human passengers to and from the International Space Station many times. But no Russian rocket has carried crew beyond low earth orbit.
Meanwhile, several other nations, notably China, have announced ambitious plans to send humans to the moon and beyond. In 2019, China achieved the world’s first (unmanned) soft landing on the far side of the moon; and in December 2020, a Chinese spacecraft successfully brought rock samples from the moon back to earth. China says it plans to land humans on the moon by 2030, with the eventual intention of establishing a manned colony there.
European Space Agency
In addition, Russia, Japan, India, and the European Space Agency have sent orbital probes to the moon. In 2019, both India and Israel tried unsuccessfully to land probes on the moon, resulting in loss of their respective spacecraft.
As we enter 2021, the ongoing exploration and penetration of space by human beings is occurring along two related but separate paths: government/military on one hand, and private/commercial on the other.
- Of these, the private/commercial ventures are accelerating much more rapidly, involving multiple projects from multiple companies, with the prospect that the private sector might achieve (if Elon Musk of SpaceX has anything to say about it) a manned mission to Mars before any national government agency does so.
- As for the government/military side of U.S. space activities, primary attention for many years has been focused on launching and monitoring a wide range of reconnaissance satellites. In addition, the U.S. government has worked cooperatively with Russia and other nations in launching and maintaining the International Space Station, which in turn is the ninth habitable space platform to orbit Earth, having been preceded by several Soviet/Russian stations including Salyut, Almaz and Mir, and the U.S. Skylab.
Meanwhile, at the direction of President Donald Trump, the U.S. established in December 2019 a new branch of the Armed Forces known as the U.S. Space Force (USSF), to become fully operational over the next 18 months. Space Force is the successor to the Air Force Space Command, originally established in 1982, and will function within the Department of the Air Force, meaning the Secretary of the Air Force has overall responsibility for the USSF under the guidance and direction of the Secretary of Defense. Additionally, a four-star general known as the Chief of Space Operations (CSO) will serve as the senior military member of the USSF.
According to the Space Force website, the USSF will organize, train, and equip space-capable forces in order to protect U.S. and allied interests in space and to provide space capabilities to the joint force. USSF responsibilities will include developing military space professionals, acquiring military space systems, and maturing the military doctrine for space operations. NASA and the Space Force will partner on matters such as space domain awareness and planetary defense, and Space Force members can also be NASA astronauts. For example, Colonel Michael S. Hopkins, the commander of SpaceX Crew-1 to the ISS, was commissioned into the Space Force on December 18, 2020.
Despite its cooperative connection with Space Force, NASA’s primary focus with respect to manned spaceflight has been and remains civilian rather than military.
Without doubt, NASA’s proudest accomplishment to this day remains the crewed missions to the moon and back during the years 1968 through 1972, a feat that to date has not been matched by any other nation or space agency. But as of 2021, that will soon change, mainly due to the efforts of various commercial/private companies.
NASA’s moon missions relied upon the magnificent Saturn V rocket, which to date is still the tallest, heaviest and most powerful launch vehicle ever brought to operational status, and the only rocket that has carried humans beyond low earth orbit. The Saturn V was designed under the direction of Wernher von Braun at the Marshall Space Flight Center in Huntsville, Alabama, with Boeing, North American Aviation, Douglas Aircraft Company, and IBM as the lead contractors.
But the Saturn V is no more. Today, NASA’s hopes for manned missions to the moon and beyond rest with the Space Launch System (SLS), potentially the biggest and most powerful launch vehicle in NASA history. Its development began in 2011 but has been plagued by delays and cost overruns. At present, the first unmanned launch of the SLS is planned for late 2021, with a possible first manned mission by mid-2023.
Meanwhile, other rockets from private/commercial developers are poised to outpace the SLS in the race for manned space travel. Top contenders include:
Space Exploration Technologies Corp.
SpaceX is an American aerospace manufacturer and space transportation services company headquartered in Hawthorne, California, founded in 2002 by Elon Musk with the main goal of reducing space transportation costs to enable the colonization of Mars. SpaceX has developed several launch vehicles, notably its Falcon 9 rocket, as well as the Dragon cargo spacecraft. SpaceX has flown humans to the International Space Station in its Dragon 2 capsule.
Of all commercial companies, SpaceX is by far the current leader in actual mission accomplishments, which include:
- the first privately funded liquid-propellant rocket to reach orbit (Falcon 1 in 2008)
- the first private company to successfully launch, orbit, and recover a spacecraft (Dragon in 2010)
- the first private company to send a spacecraft to the International Space Station (Dragon in 2012)
- the first vertical take-off and vertical propulsive landing for an orbital rocket (Falcon 9 in 2015)
- the first reuse of an orbital rocket (Falcon 9 in 2017) and
- the first private company to send astronauts to orbit and to the International Space Station (SpaceX Crew Dragon Demo-2 and SpaceX Crew-1 missions in 2020)
Notable among these achievements was the December 2015 powered vertical landing of a Falcon 9 rocket. With this achievement, the Falcon 9 became the only launch vehicle other than NASA’s now retired space shuttle to safely land after orbital flight. Since 2015, SpaceX has repeated this landing feat multiple times, including on ocean landing platforms. In March 2017, SpaceX demonstrated that it could relaunch and safely land a previously flown Falcon 9. Reusability is a key factor in Elon Musk’s strategy to lower the cost of space travel.
In September 2016, SpaceX introduced the Interplanetary Transport System, a two-stage to orbit launch vehicle. Originally nicknamed the “BFR” for “big Falcon rocket” but later dubbed Starship, the vehicle is comprised of a Super Heavy first stage and the Starship orbital second stage. Taller and heavier than the mighty Saturn V, Starship is Musk’s candidate for manned deep-space travel, including to Mars. To date, Starship has performed a number of successful suborbital test flights and landings, although a hard landing on December 9, 2020 resulted in destruction of the vehicle. Once in service, the Starship with its Super Heavy booster will be the largest operational rocket in history.
Although SpaceX is currently well ahead in the commercial space race, several other companies have entered the fray, including:
Rockeet Lab is a private American aerospace manufacturer and launch service provider, originally founded in New Zealand in 2006 by current CEO Peter Beck. The company has developed a sub-orbital sounding rocket named Ātea and a lightweight orbital rocket known as Electron designed to launch small satellites. The company established headquarters in California in 2013, and its first commercial launch occurred in November 2018 from New Zealand. Among its products are two innovative rocket engines, the Rutherford and the Curie.
Virgin Galactic is an American spaceflight company within the Virgin Group headed by Richard Branson, which aims to provide suborbital spaceflights to space tourists and suborbital launches for space science missions. SpaceShipTwo, Virgin Galactic’s current suborbital spacecraft, is air launched from beneath a carrier airplane known as White Knight Two.
Branson’s original plan for a maiden flight by late 2009 was repeatedly delayed, most seriously in October 2014 by the in-flight crash of VSS Enterprise, the first version of SpaceShipTwo. On December 13, 2018, VSS Unity finally achieved the project’s first suborbital space flight with two pilots, reaching an altitude of 51.4 miles and officially entering outer space by US standards. In February 2019, the project carried three people, including a passenger, on VSS Unity VF-01, reaching an altitude of 55.9 miles and briefly achieving in-flight zero gravity.
Blue Origin, LLC, an American privately funded aerospace manufacturer and spaceflight services company headquartered in Kent, Washington. Founded in 2000 by Jeff Bezos, the company’s strategy for cheap space travel is based, like SpaceX, on reusable launch vehicles. Blue Origin is taking an incremental approach from suborbital to orbital flight, with a focus on developing rockets that take off and land vertically.
The company began flight testing its suborbital New Shepard launch vehicle in 2015, but as of late 2020 had not yet begun commercial flights. It is also developing an orbital launch vehicle called New Glenn as well as a large rocket engine dubbed BE-4. In may of 2019, Bezos announced plans to develop a moon lander called Blue Moon, to be ready by 2024. As of 2020, Blue Origin is part of a consortium of companies working with NASA’s Artemis program aimed at returning humans to the moon.
United Launch Alliance (ULA)
United Launch Alliance (ULA), an American spacecraft launch service provider founded in 2006 as a joint venture between Lockheed Martin and Boeing.The company manufactures and operates a number of orbital and deep space rocket vehicles. Its customers include the U.S. Department of Defense and NASA.
The company currently utilizes two heavy-lift, expendable launch systems, the Delta IV Heavy and the Atlas V, with which it has orbited a variety of weather, telecom, national security and scientific satellites. In addition, a modified Atlas V is rated for human spaceflight, and to date has launched one unmanned test mission of the Boeing CST-100 Starliner, a capsule capable of carrying up to seven occupants. On that flight, the Starliner rendezvoused with the International Space Station, though it did not dock, and later landed safely in New Mexico.
As the foregoing demonstrates, humankind is making notable progress toward reliable, routine space travel. Humans could return to the moon before 2025, and a manned mission to Mars might be accomplished — if Elon Musk is correct — in less than a decade.
But what about eventual travel to another star system such as Proxima Centauri, our nearest stellar neighbor, some 4.2 light years away? Here, by most accounts, the challenge is currently beyond human capability.
The Problem in a Nutshell
Human spacecraft can’t achieve the speed required for a trip of reasonable (even survivable) duration. Say, for example, that our vehicle were traveling at the same velocity as Voyager 1, until recently the fastest-moving object ever launched by humans at roughly 38,000 miles per hour. At that speed, Voyager would take over 75,000 years to reach Proxima Centauri.
A few months ago, on September 27, 2020, NASA’s Parker Solar Probe reportedly reached a temporary velocity of roughly 290,000 miles per hour, taking advantage of a powerful gravity assist from the sun. No man-made object has ever traveled faster. But even at that speed, it would take a spacecraft roughly 9,800 years to reach Proxima Centauri.
For interstellar travel to be feasible, our spacecraft would have to achieve at least a modest fraction of the speed of light. If we could achieve 10% of light speed, for example, our trip to Proxima Centauri would take perhaps 44 years. Not impossible to imagine; but still a very long time. The problem, again, is that we simply don’t have the capability to achieve even 10% of light speed.
What we’re missing is the energy to reach such speeds. All types of spacecraft propulsion currently use some kind of chemical fuel carried within the vehicle. This puts a serious limit on maximum speed. That speed can be somewhat augmented by, for example, the sort of gravity assist utilized by the Parker Probe; but we’re still just poking along, relative to light speed.
Wanted: Warp Drive
That said, a variety of more exotic concepts have been proposed by propulsion scientists, though in practical terms we can’t do any of them — at least not yet. One example is the proposal by physicist Miguel Alcubierre for a literal version of Star Trek’s warp drive, in which the fabric of spacetime is manipulated to achieve relativistic speed. Alcubierre has stirred a lively debate as to whether his concept is even theoretically feasible within the limits imposed by Einstein’s general relativity. Meanwhile, however, the basic problem remains: even if theory permits it, colossal, probably impossible amounts of energy would be required.
As of this writing, most reputable scientists doubt that humans will ever achieve anything like warp speed technology. If that remains true, then it might also be true that Earthlings will never travel to even our closest stellar neighbors in space, and Star Trek will remain an unfulfilled dream. On the other hand, human ingenuity has busted through apparent limits time and time again. We really don’t know how to do Star Trek yet, even in theory. But a hundred years from now? Maybe.