The boundary between Earth's atmosphere and outer space has long been a focal point for both scientific inquiry and legal debate in the context of space exploration.

Traditionally, this boundary has been defined as the Kármán line, set at an altitude of 100 kilometers above Earth's surface.

However, recent research suggests that this definition might need reassessment. New findings indicate that this boundary could more accurately be situated at approximately 80 kilometers above the Earth's surface.

This revision not only holds significant implications for scientific research but may also impact future space policies and legal frameworks.

Most scientists currently agree that the boundary of outer space is established at 100 kilometers above the Earth's surface. This altitude is regarded as the limit of Earth's atmosphere, beyond which the air is so tenuous that it cannot generate sufficient resistance to maintain orbital flight.

This conventional view is attributed to the aerodynamic pioneer Theodore Von Kármán. Although Von Kármán suggested in 1963 that the boundary should be set at 100 kilometers, it is worth noting that the term "Kármán line" was coined by Andrew Haley, recognized as the world's first "space lawyer."

Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, has questioned the traditional definition of this boundary.

McDowell, who is deeply involved in compiling rocket launch records, argues that the 100-kilometer mark does not align with existing evidence, especially regarding low-orbit satellites.

He points out that numerous satellites orbit at altitudes below 100 kilometers, challenging the conventional definition. For instance, the "Electron-4" satellite operated at altitudes of 85 kilometers or lower and did not fully re-enter the atmosphere until 1997.

McDowell further analyzed atmospheric effects using satellite telemetry data provided by the North American Aerospace Defense Command. His simulations and calculations over the past 50 years revealed that atmospheric drag is relatively minimal within the altitude range of 66 to 88 kilometers.

Consequently, he argues that the Kármán line should not be set at 100 kilometers. McDowell plans to publish these findings in the *Journal of Astronautics*, offering a more precise definition for the Kármán line.

Support for this revised definition also comes from Thomas Gangale, a former US Air Force official and legal scholar. Gangale asserts in the *Journal of Space Law* that Von Kármán never advocated for setting the Kármán line at 100 kilometers in his research.

He suggests that the ongoing debate about this boundary is rooted in a misinterpretation of Von Kármán's work, which continues to influence international law and policy formulation.

Additionally, Alan Stern, a planetary scientist based in Boulder, Colorado, concurs with McDowell's findings. Stern, who serves as the chief scientist for the high-altitude balloon company Worldview, supports McDowell's redefinition of the Kármán line.

Stern underscores that while defining the boundary of outer space might seem like a matter of detail, the precise delineation is crucial for scientific research and policy development.

Clarifying the boundary between Earth's atmosphere and outer space extends beyond academic interest. It encompasses legal, international, and policy dimensions, particularly as countries like the United States have historically maintained their legal definitions of outer space.

McDowell suggests that reaching a scientific consensus on this issue could resolve numerous legal and policy challenges and foster greater international cooperation and development.

Reevaluating the Kármán line's altitude will enhance our understanding of the transition from Earth's atmosphere to outer space and support future space exploration efforts and legal frameworks.

With the increasing prominence of space travel and commercial space activities, accurately defining this boundary has become more critical than ever. Continued discussion and research by the scientific and legal communities will help establish a more solid foundation for humanity's exploration of space.