Even though the Sun is 150 million kilometers distant from us, we may feel its warmth every day. It's amazing how a far burned object can radiate heat across such a long distance.
We're not talking about temps that are hardly noticeable. Kuwait's temperature reached 63°C under direct sunshine in 2019. If you stand in such conditions for a long time, you risk dying from heatstroke.
What is most perplexing is that even when the planet scorches millions of kilometers away, outer space stays chilly. So, why is it so hot outside?
To comprehend this perplexing occurrence, it's first necessary to distinguish between two concepts that are sometimes used interchangeably: heat and temperature.
Heat vs. Temperature: What Makes It Different
Heat is the energy held inside a thing, and temperature is the measurement of that thing's hotness or coolness. As a result, when heat is transmitted to an item, the temperature of the thing rises. When the heat is taken from the item, the temperature value decreases.
Heat may be transferred in three ways: conduction, convection, and radiation.
In solids, heat is transferred by conduction. As the solid particles heat up, they begin to vibrate and clash with one another, transferring heat from hotter to cooler particles.
Convectional heat transfer is a process that occurs in liquids and gases. This mechanism of heat transmission also happens between solids and fluids near the surface.
When a fluid is heated, the molecules rise higher, carrying with them the heat energy. The finest demonstration of convective heat transmission is a room heater.
When the heater heats the surrounding air, the temperature rises and the air rises to the ceiling of the room. A convection current is created when cold air at the top is pushed to flow down and get heated.
Radiation heat transfer is a process in which an item releases heat in the form of light. Based on their temperature, all materials emit some amount of thermal energy.
All objects, including humans, emit heat as infrared radiation at ambient temperature. Thermal imaging cameras can identify objects even in the dark because of radiation.
The more a thing radiates, the hotter it is. The Sun is an excellent model of how heat is transferred across the solar system through radiation.
Space Can Burn or Freeze You; There's No in Between!
Sciencing said when an item is exposed to direct sunlight outside of the Earth's atmosphere, it will heat up to roughly 120°C. The temperature of objects on Earth and in space that does not get direct sunlight is roughly 10°C.
The heating of certain molecules that escape the Earth's atmosphere accounts for the 10°C temperature. The temperature of the empty vacuum between celestial bodies in space, on the other hand, is just 3 Kelvin above absolute zero.
The important message from this is that the Sun's temperature can only be felt if there is stuff to absorb it. Because there is practically no matter in space, it is frigid.
Two Sides of the Sun's Heat
Shaded areas are known to be chilly. The finest example is at night when temperatures drop because no radiation reaches that portion of the globe.
However, things are a little different in space. Yes, items shielded from the Sun's rays will be cooler than those exposed to sunlight, but the difference is significant.
On both sides, the item in space will experience two temperature extremes.
Take, for instance, the moon. Space.com said the portions of the moon that get sunlight will be heated to 127°C, while the dark side will be a frigid -173°C.
But why isn't the Earth affected in the same way? The Sun's infrared rays are absorbed by our atmosphere, and those that do reach the Earth's atmosphere are uniformly dispersed.
This is why, rather than experiencing excessive hotness or coolness, we experience a gradual temperature shift.
The effects of the Sun on the Parker Solar Probe are another example of temperature polarity in space. Science Times said NASA's Parker Solar Probe is a probe launched into orbit to investigate the Sun.
The probe was just 15 million miles from the Sun in April of this year. It employed a heat shield to defend itself.
When the heat shield was assaulted with solar radiation, it reached 121°C, while the remainder of the probe remained at -150°C.
Space is the Ultimate Thermos
The temperature of a system remains constant when there is nothing to heat up. This is the situation when it comes to space. Although the sun's light passes through it, no molecules or atoms can absorb the heat.
Even if the sun's energy heats a rock to over 100°C, the area around it will not absorb any heat for the same reason. There is no temperature transmission when there is no matter.
Check out more news and information on Space in Science Times.
