Question

How many miles from the surface of Earth does space begin?

Answer 1

Hint: Before we understand how far is the space from the surface of Earth, it is important to understand the concept of space with respect to planetary Earth. Also, different organisations all over the world have different standards to define the term space.

Complete answer:
In science, space is defined as the boundless three-dimensional extent wherein there are objects and events that have relative position with reference to a fixed point, commonly defined as origin. Space is commonly associated with time, to form a part of a boundless continuum called space-time.
However, in terms of the planet Earth, space is defined as what exists above the surface of the Earth. Even though the space is considered for any distance above the surface of Earth, which is gauged when we look up at the sky, it is important to define the confines of the boundary of the space in order to aid the astronauts and objects that fly across Earth to space.
Several people have tried to define the exact boundary to define the point from which space starts. In the 1900s, a Hungarian scientist by the name Theodore Von Karman fixed the boundary of the start of outer space at a distance of 50 miles above the Earth’s surface (roughly about 80 kilometres). This was termed as Karman Line.
However, the organisation National Oceanic and Atmospheric Administration of the US Department of Commerce recalibrated the Karman line to a distance of 62 miles above the Earth’s surface. This is equivalent to 100 kilometres. Similarly, the Federation Aeronautique Internationale, responsible for tracking standards in aeronautics and astronautics, defines the space line at about 100 kilometres or 62 miles, approximately.

Note: This distance of 62 miles is also, the line where it is approximately, considered as the end of the atmosphere, which is a blanket of air covering the Earth. Also, the Karman line serves as the boundary separating the outer space from the atmosphere of Earth.