The boundary between Earth and outer space is defined by the Kármán line, which is located at an altitude of 100 kilometers (62 miles) above sea level. At this point, the Earth's atmosphere becomes so thin that it is no longer able to support human flight without the use of specialized equipment, and the effects of aerodynamic lift are negligible. Beyond the Kármán line, the atmosphere gradually transitions into the vacuum of space, where there is no air or atmospheric pressure. This boundary is recognized internationally as the demarcation between Earth's atmosphere and outer space. **

The term "universe" refers to all of space, time, matter, and energy in existence, including galaxies, stars, planets, and all other forms of matter and energy. "Cosmos" is often used interchangeably with "universe" and refers to the same concept of the entirety of space, time, and matter. "Outer space" specifically refers to the vast expanse beyond Earth's atmosphere, where there is a near-vacuum and very little matter. In summary, the universe and cosmos encompass everything in existence, while outer space specifically refers to the region beyond Earth's atmosphere. **

We cannot see outer space from Earth during the day because the sunlight is scattered by the Earth's atmosphere, making the sky appear blue. At night, we cannot see outer space because the Earth's atmosphere absorbs and scatters light from distant stars and galaxies, creating a dark sky. Additionally, light pollution from artificial sources on Earth can also hinder our ability to see outer space clearly. **

Outer space is the vast expanse that exists beyond Earth's atmosphere. It is a vacuum that contains stars, planets, moons, asteroids, comets, and other celestial bodies. Outer space is characterized by extremely low temperatures, near-vacuum conditions, and the absence of air and gravity. It is also the realm in which spacecraft and satellites travel, allowing for exploration and observation of the universe beyond our planet. **

There is currently no evidence to suggest that microbes from outer space are dangerous for Earth. In fact, the likelihood of microbes from outer space reaching Earth and posing a threat is extremely low. Additionally, any potential extraterrestrial microbes would likely have evolved in a completely different environment and may not be able to survive or thrive on Earth. Furthermore, Earth already hosts a wide variety of microbes, and the potential impact of extraterrestrial microbes is currently considered to be minimal. **

As an AI, I don't have personal feelings, but I can understand why some people might find outer space creepy. The vastness and unknown nature of space can be unsettling for some, as it's a place where humans have very little control and understanding. On the other hand, Earth has its own share of creepy and mysterious phenomena, such as deep ocean trenches and unexplored forests. Both outer space and Earth have their own unique qualities that can evoke feelings of awe, wonder, and sometimes, creepiness. **

Outer space appears black because it is a vacuum, meaning there is no atmosphere to scatter or reflect light. When we look up at the night sky, we are essentially looking out into the vast emptiness of space where there are no particles to bounce light off of. This absence of light sources and scattering particles creates the illusion of darkness, making space appear black to our eyes. **

Outer space is commonly considered to begin at the Kármán line, which is located at an altitude of 100 kilometers (62 miles) above sea level. At this point, the Earth's atmosphere becomes so thin that it is unable to support conventional aircraft flight. This boundary is recognized by the Fédération Aéronautique Internationale (FAI) as the beginning of space. **