Is the deep sea/ocean on earth more dangerous than outer space?
I think it depends on how you want to measure danger. By the metric of how LONG one can stay in a vehicle before having to return to the safe and happy realm of Earth's surface, then I'd have to say deep ocean trips are more dangerous. If we want to consider how long we could survive, naked and exposed, then space wins. You could probably last a minute or so sudden exposure to the vacuum of space ( losing consciousness after 15 seconds) or so. Sudden exposure to the crushing depths of the deepest ocean would be instantaneously fatal. However, If we were to consider percentage of people who have actually DIED in attempting to explore that region, then I'd have to say space travel is more dangerous. Rockets are nasty, unpredictable brutes compared to submersibles- which, while less mobile, are far more reliable.
Is it true that space is freezing cold and without a space suit you'd get turned inside out? Why? How?
Turned inside out?No, that doesn’t happen.Freezing cold?Yes, but there is more to it.First, you might have heard space is 2.7 K. That is certainly cold, barely above absolute zero.But, space is almost a perfect vacuum. I believe there are approximately 1 atoms/meter^3 in interstellar space. So, very few atoms.But, without atoms, how can there be a transfer of heat? After all, don’t we feel heat through conduction? Without atoms to conduct our heat, how is space cold?Think about how you feel outside in the shade versus in the sunlight. If you are in the shade, heat is felt through conduction. In the sunlight, heat is felt through both conduction and the radiation from the Sun.Well, space has a temperature because of radiation. The 2.7 K temperature of space is due to the cosmic microwave background. Think of the CMB as a swath of radiation throughout all of space, giving it that 2.7 K temperature.But, a funny thing happens in space. Because there are no atoms to conduct and carry away heat, your body doesn’t freeze. At least not very quickly. So, unlike what you see in most movies, you wouldn’t instantly freeze because space is so cold. Instead, your heat would slowly radiate away.
How cold is outer space? Would someone die if they were to be bare-skinned in outer space?
The "reverse wind chill factor" (ie space is a vacuum), means there is nothing to convect your body temperature away which means even though it's very cold, this wouldn't kill you. Your skin is enough the prevent the low pressure from making your bodily fluids boil.Source: Human Body in a VacuumIf you don't hold your breath, you're likely to survive uninjured for about 30 seconds. If you do hold your breath, you're like to suffer lung damage from the pressure differential.One way or another lack of oxygen will be what gets you first.If you do have breathing apparatus of some sort (that is designed so as not to over-pressurise your lungs) then you could probably last quite a while but it definitely wouldn't be good for your health. It might even be sunburn that kills you.
Whats more dangerous underwater or space?
For space you have, 1.very low pressure 2.extremely cold 3.no breathable oxygen 4.radiation. For deep water you have, 1.very high pressure 2.very cold 3.no breathable oxygen 4.maybe some deep sea predators. Both have 4 main dangers. In space you would explode while in deep water you would implode. In space you would freeze instantly while in deep water you would slowly get colder but not freeze. In space you would suffocate from lack of oxygen while in deep water you would also suffocate from lack of oxygen. In space you would die from radiation from the sun while in deep water you might get killed by a deep sea creature (as there are many deep sea creatures that have not yet been found, that could have deadly venom and poisons etc). Space would probably be the most dangerous because you would instantly die from the cold but slowly die from the cold in deep water, and you would definitely die from radiation in space compered to taking your chances with dangerous creatures that may or may not exist in deep water.
How long would I survive on Titan without a spacesuit?
Well, the surface air pressure is 1.45x of that found on Earth, and nearly entirely made of nitrogen. The remaining 4% is methane, which is not toxic to humans. Anything else is just a trace gas. But there isn't any oxygen to breathe, so you are going to suffocate.The temperature on the surface is a very chilly −179.2 °C, so you can't just stand around in street clothes. In fact, your lungs would freeze trying to breathe the nitrogen atmosphere.And Titan's surface would be completely dark. Not only is the sun dim from that distance, but the clouds in the atmosphere absorb all of the light long before it reaches the surface.So, if you had protection from the cold and your own air, you could live indefinitely. If your use of the term "spacesuit" was meant to be a suit that survives in the vacuum of space, you don't need a pressure suit, just insulation and a standard oxygen mask mixing O2 into heated Titan air.(Well...5% methane plus oxygen is flammable, so that might be a concern.)
If outer space is a vacuum how do they measure the temperature?
If space contained nothing, we could not define a temperature for it. However all space in the universe contains microwave radiation. Physicists think of it as a "relativistic gas" with a temperature of 2.7 Kelvin.However space contains other things too. For example, it contains starlight, and that is not correctly described as a gas with a precise temperature. Generally speaking, an object has a well-defined temperature only if it has reached a state of equilibrium, or an approximation to a state of equilibrium. That's why physicists define the temperature "in the shade"; the concept of temperature in the sunlight does not make much sense, since the flow of energy is so strong that material in the sun is not in equilibrium. The state of equilibrium means that the energy flow in the substance has fundamentally distributed itself to the maximum (technically, it has reached the highest accessible state of entropy) so changes in energy distribution no longer occur.
What would happen to your body if you were in the vacuum of space, without a space suit?
Well hopefully you exhale your breath as you do this because otherwise the air you are holding in your lungs will create a great deal of pressure on the inside of your body and cause a great deal of damage. So assuming you exhale, you are now without oxygen, you can breath normally but 'nothing' is going in and out of your lungs so you will have only a few minutes before the lack of oxygen kills you. But before that kills you, the essentially non existent pressure of space will cause you to get decompression sickness 'the bends' ie the nitrogen in your blood is becoming a gas. But before that kills you will experience the unusual sensation of any exposed liquid of your body boiling off, not that because it's hot, but that the pressure is so low. You'd feel your saliva boiling off your tongue, fluid from your eyes (if they are open), and from your nose and lungs. You experience some swelling of the body due the low pressure but you won't live long enough to get the 'ballooning' effect which would make you look like a body builder by the time it's done. Also the sun will be burning any exposed flesh, but not sci fi flesh burning and flaking, more like quickly getting a sunburn type of effect. The cold would actually not be an issue because there is no air to cool you down by convection, so you'd cool done by infrared radiation, a much much slower process. Doubt you'd lose any meaningful heat by the time you died. So asphyxiation is the main thing that will kill you in a few minutes, though if picked up before that time is up you have a good chance of surviving. (The earlier the better.)
What would happen to a plant in space?
Well, it would in fact freeze if the plant was in shadow, because molecules of heat would radiate away from it. Some of the water molecules might stay in the plant, others would evaporate. The effect would be a freeze-drying process, possibly rather soon, depending on the plant. It’s unlikely that they would burst from internal pressure because plants do not have a lot of internal pressure, not as much as humans, in any case.Yes, explosive decompression is a very valid possibility for a human, say if they were “spaced,” executed by being shoved into an airlock and the pressure dumped all at once. Hint: if you ever have to jump out of a wrecked spaceship without your suit or helmet, you’ll have a few minutes—four, maybe five—to make it to the next airlock, but don’t hold your breath. Seriously. Your lungs will rupture. You’re going to get a ferocious nosebleed, your eardrums will probably rupture along with the capillaries in your skin and eyeballs. Your eyeballs will dry out very fast, so squint or close them if you can. Also, fart. It will expel the air from your intestinal tract which will also expand and give you a king-sized tummy ache. You’re also going to get the bends. The nitrogen in your system will have nowhere to go except through your muscles and blood vessels. You’d better hope they have a decompression chamber available to reverse the process or you’ll be disabled for the rest of your life. SF writers have been trying to get NASA to carry beachball-shaped rescue pods, a big, tough plastic bubble that can be quickly zipped from the inside and carries enough air for about an hour. But NASA likes spacesuits, which take an hour to get into and require help in both micro-gravity and on Earth. So if the ISS takes a big meteorite, those that don’t die from the immediate impact—there will be a huge flash of oxidation, too—are going to die, painfully and kinda slowly, aware of it the whole time. Ugly way to go.