Mentari Puspadini, CNBC Indonesia
Tech
Saturday, 29/07/2023 21:00 WIB
Photo: Illustration of a sore ear. (Doc. Freepik)
Jakarta, CNBC Indonesia – Have you ever had an earache while on a plane? It turns out that this phenomenon is related to the presence of the ‘end of the sky’ which borders outer space, you know! How come?
The limit of the sky with outer space has long been detected by experts. This boundary is known as the Karman Line.
The Karman line is named after Theodore von Karman, a Hungarian-American physicist in 1957. He was the first person to try to define the boundary between Earth and space.
According to NASA, each layer of the atmosphere plays a role in ensuring that Earth can support all types of life. Their functions range from blocking cancer-causing cosmic radiation to creating the pressure needed to produce water.
“As you get farther from Earth, the density of the atmosphere decreases,” said Arizona State University space physicist Katrina Bossert.
“The composition also changed, and lighter atoms and molecules began to predominate, while the heavier molecules remained closer to the Earth’s surface.”
As an object moves upwards into the outermost layers of the atmosphere, the pressure drops dramatically. Although airplanes have pressurized cabins, rapid changes in altitude can affect the eustachian tube.
“This is why your ears may feel popping during takeoff on an airplane,” says Matthew Igel, of the University of California.
Eventually, the air became too thin for conventional planes to fly. This point is the area that scientists have defined as the end of the sky and the beginning of outer space.
The purpose of establishing the Karman line is not only for aircraft limits, but also used to ensure spacecraft are able to leave Earth and ensure satellites can orbit the earth.
“The Karman line is an approximation of the area indicating the altitude at which a satellite can orbit the Earth without burning up or falling out of orbit before it has circled the Earth at least once,” explained Bossert.
Bossert explained there are various factors determining how much air resistance there is. It’s like the size and shape of a satellite. Air resistance impacts the satellite’s ability to orbit the Earth.
Satellites in low Earth orbit are classified as flying at a height of less than 1,000 km. However, there are also those whose orbits are about 160 km above the Earth’s surface.
Bossert said a satellite that is in low Earth orbit will crash in a few years. The reason is “the pull from Earth’s upper atmosphere gradually slows the orbital speed”.
Another explanation comes from Igel. According to him, the Karman line is defined as a distance of 100 kilometers above the earth. However, it is not impossible that there are orbiting below that line.
It is possible for an object to orbit the Earth at an altitude below the Kármán line, but that would require a very high orbital speed, which would be difficult to sustain due to friction.
“Therein lies the feeling one should have for the Karman line: It is an imaginary but practical threshold between air travel and space travel,” he explains.
Watch the video below:
Video: Satria-1 Satellite Successfully Flying With Elon Musk’s Rocket
(dce)
2023-07-29 14:00:00
#Mystery #Ear #Pain #Flying #Plane #Revealed
