What’s Outside Space?
By: Loops Facts
Tags: Time Out Space, Science, Space, Space Exploration, Space Travel

Outer space is the expansion that exists beyond the Earth and between celestial bodies. The outer space is not completely empty — it is a hard vacuum that has a low density of particles, mainly a plasma of hydrogen and helium, as well as electromagnetic radiation, magnetic fields, neutrinos, dust, and cosmic rays. The base temperature of outer space determined by background radiation from the Big Bang is 2.7 Kelvin (45270.45 ° C; 4454.81 ° F). Approximately half of the baryonic (ordinary) matter in the universe consists of plasma between galaxies; It has a density of less than one hydrogen atom per cubic meter and a temperature of millions of Kelvin. Local concentrations of matter have condensed into stars and galaxies. Studies indicate that most galaxies have 90% mass in an unknown form, called dark matter, which interacts with the other matter through gravity, but not electromagnetic force. Observations reveal that much of the mass-energy in the observable universe is dark energy, a type of vacuum energy that is poorly understood. The vast majority of space occupies space, but even galaxies and star systems have almost completely empty space.

Outer space does not start at a certain height above the Earth’s surface. The Personnel Line, located at an altitude of 100 km (62 mi) above sea level, is traditionally used in space treaties to record outer space debuts and aerospace records. The framework of international space law was established by the Outer Space Treaty, which came into force on 10 October 1967. The treaty does not incorporate any claim to national sovereignty and allows all states to independently explore outside space. Despite drafting UN resolutions for the peaceful use of outer space, anti-satellite weapons have been tested in Earth orbit.

Humans began the physical exploration of space during the 20th century with the advent of high-balloon flights. This was followed by the rocket flights of the crew and then, in 1961, for the first time in Earth orbit, achieved by Yuri Gagarin of the Soviet Union. Due to the high cost of going into space, the human spacecraft is limited to low Earth orbit and the Moon. On the other hand, all known planets in the solar system have reached the spacecraft.

Outer space represents a challenging environment for human exploration due to the dangers of vacuum and radiation. Microgravity also has a negative effect on human physiology which causes muscle atrophy and bone loss. Apart from these health and environmental issues, the economic cost of putting objects, including humans, into space is very high.

According to the Big Bang theory, the very early universe was an extremely hot and dense state about 13.8 billion years ago [9], which rapidly expanded. About 380,000 years later the universe was sufficiently cold to allow protons and electrons to form hydrogen and the so-called recombination era. When this happened, matter and energy decomposed, allowing the photon to travel freely through the continuously spreading space. The case that remained after the initial expansion has come since the fall of gravity to form stars, galaxies, and other celestial bodies, leaving behind a deep vacuum that is now called outer space. Since light has a finite velocity, this theory also constrains the shape of the directly observable universe. These leaves open the question of whether the universe is finite or infinite.

The current shape of the universe has been determined from measurements of the cosmic microwave background using satellites such as the Wilkinson microwave anisotropy probe. These observations indicate that the spatial geometry of the observable universe is “flat”, meaning that photons on a parallel path at a point remain parallel, as they travel to the space of the observable universe, leaving the local universe.

The present-day shape of the universe has been determined from measurements of the cosmic microwave background using satellites such as the Wilkinson microwave anisotropy probe. These observations indicate that the spatial geometry of the observable universe is “flat”, meaning that photons on a parallel path at a point remain parallel, as they travel to the space of the observable universe, leaving the local universe. The flat universe, combined with the measured mass density of the universe and the accelerated expansion of the universe, shows that space has non-zero vacuum energy, called dark energy.

Estimates are equivalent to 5.9 protons per cubic meter of the average energy density of the present-day universe, including dark energy, dark matter, and baryonic matter (simple matter composed of atoms). Atoms account for only 4.6% of the total energy density or a density of one proton per four cubic meters. The density of the universe is clearly not uniform; This ranges from relatively high densities in galaxies — including very high densities in structures within galaxies, such as planets, etc. Stars and black holes — positions in huge voids whose density is very low, at least in terms of visible matter. Unlike matter and dark matter, dark energy is not concentrated in galaxies: although mass in the universe may account for the majority of energy, the effect of dark energy is 5 orders of magnitude smaller than the effect of gravity by matter. And Dark Matter within the Milky Way.

Outer space is the closest known approximation to a complete vacuum. This is effectively no friction, which allows stars, planets, and moons to move freely along their ideal orbits, following the initial formation phase. Space is not devoid of the deep vacuum substance of space, because it contains a few hydrogen atoms per cubic meter. By comparison, the air humans breathe contains about 1025 molecules per cubic meter. The low density of matter in outer space means that electromagnetic radiation can travel large distances without scattering: the average free path of a photon in space is about 1023 km or 10 billion light-years. Despite this, extinction, which is the absorption and scattering of photons by dust and gas, is an important factor in galactic and space astronomy.

Stars, planets, and moons maintain their atmosphere by gravitational attraction. There is no clear upper limit for atmospheres: the density of atmospheric gas gradually decreases with distance from the object until it becomes indistinguishable from outer space. The Earth’s atmospheric pressure falls to about 0.032 pA at an altitude of 100 kilometers (62 mi) compared to the 100,000 pA of the International Union of Pure and Applied Chemistry (IUPAC) of standard pressure. Above this altitude, the pressure of isotropic gas becomes increasingly insignificant compared to the radiation pressure from the Sun and the dynamic pressure of the solar wind. The thermosphere of this range has large gradients of pressure, temperature, and composition, and varies greatly due to space weather.

The temperature of outer space is measured in terms of the kinetic activity of the gas, as it is on Earth. Radiation from outer space has a different temperature than the kinetic temperature of the gas, which means that the gas and radiation are not in thermodynamic equilibrium. All observable universes are filled with photons that were created during the Big Bang, known as Cosmic Microwave Background Radiation (CMB). (There is a large number of very large neutrinos known as cosmic neutrino backgrounds.) The current black body temperature of background radiation is about 3 K (−270 ° C; 4454 ° F). Gas temperature in outer space can vary widely. For example, the Boomerang Nebula has a temperature of 1 K, while the solar corona reaches a temperature of 1.2–2.6 million K.

Despite harsh environments, many life forms have been detected that can withstand extreme location conditions for extended periods. The species of lichen carried at the ESA bio pen facility remained at risk for ten days in 2007. The seeds of Arabidopsis thaliana and Nicotiana tabacum germinated after being in space for 1.5 years. There are 559 days left when a strain of Bacillus subtilis, which is exposed to the Earth’s orbit or a simulated martyr environment. The hypothesis of lithopanspermia suggests that rocks emanating from life-exploiting planets into outer space can successfully transport life forms to another habitable world. One speculation is that just such a scenario occurred in the history of the solar system, in which potential microorganism-bearing rocks were exchanged between Venus, Earth, and Mars.

Even at relatively low altitudes in the Earth’s atmosphere, conditions are unfavorable to the human body. The altitude where atmospheric pressure corresponds to water vapor pressure at human body temperature is called the Armstrong Line, named after the American physician Harry G. Armstrong. It is situated at an altitude of about 19.14 km (11.89 mi). Over or above the Armstrong line, fluid is boiling in the throat and lungs. More specifically, bodily fluids such as saliva, tears, and fluid in the lungs are boiling. Therefore, at this height, human existence needs a pressure suit or pressurized capsule.