Common questions about Outer space

Short answers, pulled from the story.

What is the definition of outer space according to the Kármán line?

The Kármán line is set at an altitude of 100 kilometers as a working definition for the boundary between aeronautics and astronautics. This line is named after Theodore von Kármán, who argued for an altitude where a vehicle would have to travel faster than orbital velocity to derive sufficient aerodynamic lift from the atmosphere to support itself. The Fédération Aéronautique Internationale and the United Nations use this 100 kilometer altitude internationally.

Who first measured the distance to the nearby star 61 Cygni and when did this occur?

The German astronomer Friedrich Bessel successfully measured the distance to the nearby star 61 Cygni in 1838. This measurement showed the star had a parallax of just 0.31 arcseconds, corresponding to a distance of over 10 light years. This discovery helped astronomers begin to measure the vast distances between stars in the 19th century.

What happens to human fluids when exposed to the pressure of the Armstrong line?

At the Armstrong line, which is an altitude of around 100 kilometers, fluids in the throat and lungs boil away due to the matching vapor pressure of water at the temperature of the human body. This condition is called ebullism and occurs when pressure drops below 6.3 kilopascals. Exposed bodily liquids such as saliva, tears, and liquids in the lungs boil away, causing the body to bloat to twice its normal size.

When was the Outer Space Treaty passed and which countries signed it in 1967?

The Outer Space Treaty was passed by the United Nations General Assembly in 1963 and signed in 1967 by the Union of Soviet Socialist Republics, the United States of America, and the United Kingdom. As of 2017, 105 state parties have either ratified or acceded to the treaty. The treaty states that outer space is free for all nation states to explore and is not subject to claims of national sovereignty.

What is the warm hot intergalactic medium and how does it form?

The warm hot intergalactic medium is a rarefied plasma organized in a galactic filamentary structure that heats up to temperatures of 105 K to 107 K when gas falls from voids. This plasma contains filaments of higher density, about one atom per cubic meter, which is 5, 200 times the average density of the universe. Computer simulations and observations indicate that up to half of the atomic matter in the universe might exist in this warm, hot, rarefied state.

When did Voyager 1 become the first man-made object to leave the Solar System?

In August 2012, Voyager 1 became the first man-made object to leave the Solar System and enter interstellar space. This event marked a significant milestone after the spacecraft had performed fly-bys of the Moon and other planets. The placing of artificial satellites in Earth orbit has produced numerous benefits, including relay of long-range communications and precise navigation.

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