Circling the earth in the orbital spaceship, I marveled at the beauty of our planet.  “People of the world!  Let us safeguard and enhance this beauty — not destroy it!”   —Yuri Gagarin

Yuri Gagarin

It was 50 years ago today that the 108-minute orbital flight of Yuri Gagarin ushered in the modern space era.  On April 12, 1961, the 27-year old Gagarin made his way in the early morning to the Baikonur Cosmodrome in what is now Kazakhstan.  The launch pad from which he took off in the rocket that carried the single-man Vostok 1 spacecraft remains in use today:  the latest crew of the International Space Station was launched from the same site last week, and to this day cosmonauts ritually stop on the way to “take a leak,” just as Gagarin did that morning.  Gagarin completed a single orbit in his spacecraft before returning to Earth, ejecting himself from the craft at an altitude of about 4 miles and returning to land by parachute.  It was only a few years later, in 1968, that Gagarin would die in a routine training accident, shortly after he had been scheduled for a second mission into space. 

The launching of the “space race” is one that drew humanity together in a time when the world was plagued by the political divisions of the cold war.  To be sure, there was competition between Americans and Soviets in reaching landmark achievements in the exploration of space, but the world also saw the accomplishments of Gagarin, Armstrong, and others more majestically as the accomplishments of Man.  Many of my personal friends were influenced to pursue careers in astronomy and physics because of the excitement of exploration those role models exemplified.  And it is with a certain sadness that they note that it has been almost 40 years (December 19, 1972) since a human being walked on the surface of the Moon.  Like all things, the nature of Man’s relationship with space has changed, as perhaps most iconically exemplified at the moment by the planned termination of the U.S. Space Shuttle program. 

Today, the most pressing concerns for outer space are not its exploration as much as they are its commercial uses.  There are the numerous satellites that have been placed in orbit over the years to provide telecommunications services, resulting in the need to manufacture uplink and downlink terminals, transponders, mobile satellite telephone units, direct-to-home receivers, and other components in addition to the satellites themselves.  There is the use of satellite imagery in the fields of agriculture, geology, forestry, biodiversity conservation, military intelligence, and others, as exemplified by the GeoEye, DigitalGlobe, Spot Image, RapidEye, and ImageSat International projects.  There are the proliferation of satellite navigation systems in the form of global positioning systems in the United States, and the development of similar systems in Russia (GLONASS), China (Compass), and Europe (Galileo).  There is the current development of high-altitude platforms, which are quasi-stationary aircraft that may be deployed at altitudes of 17 – 22 km to provide services for several years.  There are even examples of space tourism as exemplified by Dennis Tito’s tourist flight to the International Space Station in 2001; several companies are now planning “economical” suborbital flights to altitudes of some 100 – 160 km so that tourists can experience the weightlessness and striking views of being in outer space. 

But where is outer space exactly?  The question is not an idle one and can have numerous effects because it defines what law is applicable:  is it the law as embodied in one of the five U.N. treaties related to space or is it a national aviation or other law of the sovereign territory “below” the relevant location?  Historically, the property law was deceptively simple:  “Cuius est solum, eius est usque ad coelum et ad inferos” (“the owner of the land owns everything up to the sky and down to the center of the earth”).  The simple idea that each of us owns all of the airspace above our homes is a quaint one but hopelessly unrealistic in modern times. 

As a principle of private ownership, usque ad coelum was soundly rejected by the U.S. Supreme Court in United States v. Causby when Thomas Lee Causby complained that flights of military aircraft at an altitude of 83 feet to a nearby Greensboro airport during World War II were so frightening to his chickens that he was forced to abandon his farm business.  The Supreme Court held that the airspace was a “public highway,” and that while a landowner might be entitled to compensation from the government, he has no right to prevent use of the airspace.  A copy of the decision can be found here.

The doctrine retains relevance in the form of national rights.  The 1944 Chicago Convention on International Civil Aviation asserts that “[e]very state has complete and exclusive sovereignty over airspace above its territory,” leading on occasion to international disputes when aircraft intentionally or accidentally enter another country’s airspace.  A copy of the Convention can be found here. 

But  just as Causby was frustrated by national rights superseding his private rights, so too nations may be frustrated by having a limit to the extent of their airspace rights.  The Outer Space Treaty rejects national rights over outer space, declaring that “the exploration and use of outer space shall be carried out for the benefit and in the interests of all countries and shall be the province of all mankind.” 

So far, there is no internationally recognized limit where national airspace ends and outer space begins.  When the topic has come up in past international discussions, it has generally been decided that there was no current need for a hard definition.  Indeed, the topic was again one focus of the 50th session of the Legal Subcommittee of the U.N.’s Committee on the Peaceful Uses of Outer Space last week.  During that session a number of potential ways of defining outer space were considered, including both physical definitions and functional definitions.  The various definitions that have been floated over the years appear to be converging around an altitude of 100 km, particularly at the von Kármán line where the Earth’s atmosphere becomes too thin for aeronautical purposes.  It is at the von Kármán line that a vehicle would have to travel faster than orbital velocity to derive adequate aerodynamic lift from the atmosphere to support itself. 

It is worth noting that even at altitudes far greater than 100 km, there are already disputes.  The geostationary orbit has a period equal to the Earth’s rotational period so that satellites placed in that orbit appear stationary relative to the Earth.  It occurs directly above the geographic equator at about 36,000 km.  In 1976, eight countries through which the equator passes (Brazil, Colombia, Ecuador, Indonesia, Congo, Kenya, Uganda, and Zaire) signed the Bogota Declaration to assert their claim that the geostationary orbit is a “scarce national resource” that is not a part of outer space.  Since the Declaration was signed, other equatorial nations have asserted claims of ownership to their overhead geostationary arcs.  Thus far, the Declaration has been ignored by nations wishing to place satellites in the geostationary orbit, and while the issue of the Bogota Declaration is repeatedly discussed at the U.N., it has been given no legal recognition.  A copy of the Declaration may be found here.

Even though only a handful of humans have been in outer space, it has always and still holds a fascination for us.  Just as we do, our ancient ancestors looked up at the sky — the Sun, the Moon, the stars — and saw reflections of every aspect of our humanity, whether it be romance or war.  To me, the legal issues of how we deal with outer space are, in their own way, just as fascinating as the scientific ones.