Nope.
NO
No, humans could not live on Neptune. Neptune's extreme cold temperatures, high wind speeds, and lack of a solid surface make it inhospitable to humans. Additionally, the planet's atmosphere is mainly composed of hydrogen and helium, which are not breathable for humans.
No. Humans could not live on Neptune. The planet is extremely cold, its atmosphere is not breathable, and there is no solid surface to stand on. Although in the distant future we could see a space station in orbit around Neptune which would send probes, and ships into the atmosphere for scientific study.
Without a suit? No, the planet's atmosphere is thin and without oxygen.
yes they can. they actually used to live without humans in herds, until they were domesticated by humans and used for traveling purposes. there are still about 25,000 wild herds of horses.
yes. no.
we can not live without water, vegetables, protein and meat. Foods that we could live without are greasy foods,soft drinks and some other rich in fat and sugar foods.
troposphere
The layer of the atmosphere in which humans live is called the troposphere. It is the lowest layer of the atmosphere and is where weather events occur, as well as where most of Earth's air mass is concentrated.
Humans cannot currently live on the moon without significant life support systems. The moon lacks a breathable atmosphere, protection from harmful radiation, and extremes in temperature that make it uninhabitable for humans without proper technology and infrastructure.
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Yes humans can live with out heads if they are an zombie.