"The average temperature of outer space near Earth is 283.32 kelvins (10.17 degrees Celsius or 50.3 degrees Fahrenheit). In empty, interstellar space, the temperature is just 3 kelvins, not much above absolute zero, which is the coldest anything can ever get."
https://sciencing.com/temperatures-outer-space-around-earth-20254.html
"Thermal energy, or heat, is the energy that comes from the movement of atoms and molecules in a substance. Heat increases when these particles move faster. Geothermal energy is the thermal energy in the earth."
https://www.eia.gov/energyexplained/what-is-energy/forms-of-energy.php
"Temperature in outer space depends on many factors: distance from a star or other cosmic event, whether a point in space is in direct light or shade and if it is subject to a solar flare or solar wind. Variation in the temperature of space near the Earth is primarily based on location and time: Temperatures are drastically different on the light and shaded sides of the planet, which gradually change minute to minute based on the planet's rotation on its axis and its revolution around the sun."
"At the orbit of the earth the average solar wind consists of a strongly ionized gas having a proton and electron density of about 3 - 10 particles per cubic centimeter, with an average flow velocity of approximately 400 km/s. Occasionally stream structures are detected in the steady solar wind, which have peak velocities which tend toward a mean of about 750 km/s near the earth."
https://umbra.nascom.nasa.gov/spartan/the_solar_wind.html
"The sun is very hot, and it's a plasma.
HOST PADI BOYD: Stars, like our sun, are made of very hot gasses. The sun is so hot that most of its gas has been ionized into a plasma.
HOST PADI BOYD: When those plasma particles leave the sun and head out in all directions into space, we call that solar wind and we now know that every planet in our solar system encounters some of that plasma."
https://www.nasa.gov/mediacast/plasma-plasma-everywhere
""If spacetime is a kind of fluid, then we must also take into account its viscosity and other dissipative effects, which had never been considered in detail".
Liberati and Maccione catalogued these effects and showed that viscosity tends to rapidly dissipate photons and other particles along their path, "And yet we can see photons travelling from astrophysical objects located millions of light years away!" he continues. "If spacetime is a fluid, then according to our calculations it must necessarily be a superfluid. This means that its viscosity value is extremely low, close to zero"."
https://phys.org/news/2014-04-liquid-spacetime-slippery-superfluid.html
"a mixture of hydrogen and helium.
The Plasma electric universe theory is a hypothesis that the behaviour of ionized gas plays a major role in the structure of the large scale universe"
https://www.dapla.org/plasma-universe-theory/
"That hydrogen wall is the outer boundary of our home system, the place where our sun's bubble of solar wind ends and where a mass of interstellar matter too small to bust through that wind builds up, pressing inward. Our host star's powerful jets of matter and energy flow outward for a long stretch after leaving the sun — far beyond the orbit of Pluto. But at a certain point, they peter out, and their ability to push back the bits of dust and other matter — the thin, mysterious stuff floating within our galaxy's walls — wanes. A visible boundary forms. On one side are the last vestiges of solar wind. And on the other side, in the direction of the Sun's movement through the galaxy, there's a buildup of interstellar matter, including hydrogen."
https://www.livescience.com/63297-hydrogen-wall-glowing-interstellar-space.html