How close to the Sun can you get without burning up?
Heat coming off the sun dissipates over distance, but a person drifting in space would begin encountering that kind of heat (the five-yard line) some three million miles from the sun. “It would then be a matter of time before the astronaut died,” Mcnu*tt says.
first, we can feel the sun's heat from 150 million kilometres because: the sun emmits MASSIVE ammounts of heat and other radiation, so much that at this distance we still receive over a thousand watts per square meters.
A difference of one mile either way would make absolutely no difference whatsoever to life on Earth. The distance between Earth and Sun varies by three and a half MILLION miles during one orbit: the orbit has a minimum radius of 91 million miles and a maximum of 94.5 million miles.
“If the Earth was one inch closer to the Sun, would we all burn to death?” Nope. Not even close. In fact, the Earth gets about *three million miles* closer to, and farther from, the Sun every year.
Well, there is no “surface” of the sun. It just gradually peters off into spaaaace. There is a point at which the plasma becomes translucent, so the light can escape, but even that is a tenuous layer, thousands of miles thick, and very low pressure, so you can neither point to it nor stand on it.
Space, however, is a vacuum—meaning it's basically empty. Gas molecules in space are too few and far apart to regularly collide with one another. So even when the sun heats them with infrared waves, transferring that heat via conduction isn't possible.
The boundary between the Sun's interior and the solar atmosphere is called the photosphere. It is what we see as the visible surface of the Sun. The photosphere is not like the surface of a planet; even if you could tolerate the heat, you couldn't stand on it.
The Kármán line is a boundary 62 miles (100 kilometers) above mean sea level that borders Earth's atmosphere and the beginning of space. However, defining exactly where space begins can be rather tricky and depends on who you ask.
As you drill deeper into the Earth's interior, the temperature increases due to the geothermal gradient, which is the rate of temperature increase with depth in the Earth's crust and mantle. On average, the geothermal gradient is about 25 to 30 degrees Celsius per kilometer (77 to 86 degrees Fahrenheit per mile).
It wouldn't be good. At the Equator, the earth's rotational motion is at its fastest, about a thousand miles an hour. If that motion suddenly stopped, the momentum would send things flying eastward. Moving rocks and oceans would trigger earthquakes and tsunamis.
Can we live without the sun?
All plants would die and, eventually, all animals that rely on plants for food — including humans — would die, too. While some inventive humans might be able to survive on a Sun-less Earth for several days, months, or even years, life without the Sun would eventually prove to be impossible to maintain on Earth.
Stars like our Sun burn for about nine or 10 billion years. So our Sun is about halfway through its life. But don't worry. It still has about 5,000,000,000—five billion—years to go.
Earth will be scolded and become bone-dry. In about 5.5 billion years the Sun will run out of hydrogen and begin expanding as it burns helium. It will swap from being a yellow giant to a red giant, expanding beyond the orbit of Mars and vaporizing Earth—including the atoms that make-up you.
Even in Antarctica, the coldest place on our planet, temperatures seldom drop below minus 50°C. Without the sun's radiation, the temperature would be anywhere near the absolute zero of minus 273°C. Life would have never continued nor even have come into existence.
The Sun does not have a solid surface like a planet. Instead, it is composed mainly of plasma, which is a hot, ionized gas. The Sun's structure consists of several layers, including the core, radiative zone, convective zone, photosphere, chromosphere, and corona.
Touching the Sun is not possible for humans, as the Sun is a massive, extremely hot ball of gas. If a human were to somehow approach the Sun, they would be exposed to intense heat and radiation, which would be instantly fatal.
We can't smell space directly, because our noses don't work in a vacuum. But astronauts aboard the ISS have reported that they notice a metallic aroma – like the smell of welding fumes – on the surface of their spacesuits once the airlock has re-pressurised.
In space or on the Moon there is no atmosphere to scatter light. The light from the sun travels a straight line without scattering and all the colors stay together. Looking toward the sun we thus see a brilliant white light while looking away we would see only the darkness of empty space.
If we were above the atmosphere, say on the International Space Station and looked at the sun (through our filtered visor), the sun would appear white! Why? Because though the sun emits strongest in the green part of the spectrum, it also emits strongly in all the visible colors – red through blue (400nm to 600nm).
Parker Solar Probe now holds the record for closest approach to the Sun by a human-made object. The spacecraft passed the current record of 26.55 million miles from the Sun's surface on Oct.
What is our sun made of?
The Sun is a huge, glowing sphere of hot gas. Most of this gas is hydrogen (about 70%) and helium (about 28%). Carbon, nitrogen and oxygen make up 1.5% and the other 0.5% is made up of small amounts of many other elements such as neon, iron, silicon, magnesium and sulfur.
To live on Mars, we would need technology to protect us from radiation, supply breathable air, and provide warmth. Scientists and engineers are exploring solutions such as building habitats underground or using Martian soil to shield against radiation.
Remarkably, life on Earth only has a billion or so years left. There is some uncertainty in the calculations, but recent results suggest 1.5 billion years until the end. That is a much shorter span of time than the five billion years until the planet is engulfed by the Sun.
In the 1900s, Hungarian physicist Theodore von Kármán determined the boundary to be around 50 miles up, or roughly 80 kilometers above sea level. Today, though, the Kármán line is set at what NOAA calls “an imaginary boundary” that's 62 miles up, or roughly a hundred kilometers above sea level.
Outer space does not begin at a definite altitude above Earth's surface. The Kármán line, an altitude of 100 km (62 mi) above sea level, is conventionally used as the start of outer space in space treaties and for aerospace records keeping.
