Why do scientists believe earth is the only planet with life as you know it?
Earth is the only planet known to have life on it, however with the vastness of space the likelihood of life not existing anywhere else is astronomically low. We just havent found it yet.
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So far, Earth seems to be the only planet in our solar system with abundant carbon-based lifeforms. There are likely some remnants of such life on the other solar planets, if …only as transplanted by meteoric collisions with Earth. It is unknown if the conditions for Earth-like life exist elsewhere, or if any actually developed in those conditions. Life has not yet been found anywhere else other than on Earth. So, to answer your question - to the best of our knowledge to date, yes.
It is not clear that Earth is the only planet with life. For all we know there might be, and most astronomers expect that there probably are, planets with life on them orbit…ing a significant fraction of the hundreds of billions of stars in each of the hundreds of trillions of galaxies in the universe. Present technology is barely able to detect that planets are there orbiting other stars, we cannot yet tell whether any exoplanets (as planets of other stars are called) have life on them. As for the other planets in this solar system, Mercury and Venus are too hot to have liquid water on them, and Neptune and Uranus are too cold to have liquid water on them. Mars might have life remaining in its underground water, and there are speculations that life of a sort might be possible on Jupiter, Saturn, and the moon Titan, but (a) that's a long shot, and (b) we haven't looked yet. A previous answer to this question said that Earth is the only planet with life because it is the only planet with nitrogen. That is utterly wrong. Mars, and Titan also have atmospheres consisting mostly of nitrogen, besides which nitrogen is a minor constituent of the atmospheres of Venus, Jupiter, Saturn, Uranus, and Neptune.
Because it is the perfect length away from the sun so it will not burn through the atmosphere
Earth is a great planet because, Earth is just right where it is, if Earth was closer to the Sun then it would be too hot and the water like lakes and oceans would boil and th…ere will be no water.. But if we were farther away then it would be really cold to live on Earth.. We are living on Earth because it is just right to be living on it.
The operative part there is "so far as (we) know". Although dozens of extra-solar planets have been discovered, as well as the other seven or eight in our solar system, our s…cience so far is unable to determine if any of them have "life", as least "life" as we know it. Our definition of life is 'earth-based', in other words we can only define life by the kinds of lifeforms we observe here on earth. So if we can't imagine any life forms from earth existing on other planets, we say they are "lifeless". This may or may not be true, but we don't have any other way do define life.\n. \nCertain moons of the outer planets have what may be the proper environment for some kinds of life - Europa, or Io for example. We believe there may be liquid water there, in some areas, and that is one of the major requirements for life. We don't believe that intelligent life forms can exist on frozen planets, or those with barren rocky surfaces and high temperatures - Mercury and Venus, for example. Jupiter and Saturn are huge balls of gas, and probably don't have any solid surface - so if any life forms exist there, they'd have to be wildly different from anything we know here. Neptune and Uranus are similar gas balls, but we're not sure if they have any life. They are so far from the Sun, and so cold, that life as we know it could not exist there.\n. \nMany people believe that Mars once had life of some sort, because there is evidence that Mars had liquid water, and some atmosphere. Our probes there now are searching for any thing that would support that hypothesis.\n. \nWe just don't know enough about the planets we've discovered around other stars yet. However, given the number of stars, and the number of planets we've discovered, it would be foolishly earth-centric to believe that we are the ONLY life in the universe. The cosmos is probably teeming with life, we just haven't recognized it yet.
Earth is the only planet that has life on it because it is just the right temperature to grow plants, and as you know,that plants give us oxygen to breathe in which is why me …and you are alive right now!! If you ask someone why is there no life in Mercury, he/she will say that mercury is way too close to the sun and is too hot to grow any plants. Therefore Earth gets the right amount of heat to grow plants in. A Extra Fact Earth is the only planet we've taken a really close look at. For all we know, there are half a dozen other planets and moons in our system supporting life at this very moment.
Earth is the only planet "so far" - we've only just begun to explore other planets. Earth is the only planet with enough oxygen to sustain life. Also, the ozone layer prote…cts us from the harmful rays that come from the sun.
Scientists do NOT Believe anything. They use known information and theories that are supported by some evidence to try to make reasonable explanations. Some people also it w…as created by god. Answer Earth formed about 4.6 billion years ago along with the other planets in this Solar System. Heavy elements (those that are present in the current Solar System) had to have been formed by then, perhaps as a result of a pre-Sol supernova (where Sol is the name of the star at the centre of this Solar System, also known as the Sun). The heavy elements would have accumulated together via gravity. The larger the collection of elements, the more would have been attracted (the greater the mass, the greater the gravity, or, within the talk of General Relativity, the greater the space-time warpature). The collection would have continued via gravity, forming stones, then boulders, then meteor-sized objects. The coalescence of these meteors would have formed items as massive as planets, such as the Earth. This is the story science has managed to envisage so far.
In our solar system, Earth is in a favorable position with idealtemperatures for life not too close to the Sun (where water wouldbe gaseous) and not to far away (where water w…ould be solid and itwould be a frozen world). Tidal effects are also believed favorableto life; as is the Earth's powerful magnetic field which helpsprevent the atmosphere being swept away by the solar wind as mayhave happened on Mars, leaving it dry and arid. Some scientistsindicate our solar system is also in a favorable position in thegalaxy in terms of distance from the galactic core. Current thinking is that there may be as many as 40 billionEarth-liike planets just in our galaxy alone and that likely manyof these are likely to have life on them. It's also possible theremight be life in subsurface oceans in moons of our gas giantsJupiter and Saturn, like Europa, Encedalus, and Titan - whoseoceans are liquid because of warming effects from tidal forces.
cell form and larva in the water witch grew to fish to monkey to man
Not all scientists believe this. The topic of Earth being the only planet in the known universe to support life has been and still is a heated debate amongst many scientists.
Their has been evidence on more they one planet that ice and water were their with can led to a form of live . One is mars. But no evidence confirming that live was their has …bee yet discovered.
In Planetary Science
In Planetary Science
You need water to live and other planets don't have water
In Planetary Science
Actually not exactly... They think MARS can have life. They found WATER on mars, so, no, Earth might not be the only planet with life.
In Planetary Science
There is life due to the following reasons: 1) Atmosphere: Our atmosphere has the correct thickness to filter the harmful UV radiations from the Sun. Although not essentia…l for all life, oxygen is important for much of the life on Earth. 2) The temperature seems to be almost ideal. 3) Liquid surface water - Life started in water. It is a precious resource needed to sustain all life, as we know it. For more details, visit the link below.
In Planetary Science
Earth is only one planet on solar system which has sustainable atmosphere. In other words, Earth got all the factors that can support the life. Edit: Temperature is important… too, and liquid water seems to be essential.