The nearest planets, orbiting within a distance similar to Earth's orbit around Sun, are trillions (1,000,000,000,000 = one trillion) of miles away. The first planet, of this kind, was confirmed in 1992, according to some websites. Water, which appears necessary in sustaining life, has not been detected on any of these Earth like planets. The five closest planets orbiting around distant stars are extremely brief, compared to Earth, which completes orbit around the Sun (a star named Sol) in about 365 days.
Even microscopic life needs time to adjust to dramatic changes, which occur during dry seasons and rainy seasons. In other areas Summer climates are much warmer than Winter conditions. Not only plants but also animals need time to adjust to profound variations in the weather. Spring and Fall allows complex life forms a chance to adjust and reproduce, before weather conditions become harsh.
Evidence of the closest Earth-like planets was produced decades ago, in many cases. In other cases, light - the fastest moving phenomenon known - was emitted from these planets centuries ago. Plenty of large asteroids and comets roam through the universe; and any of these newly detected, distant planets could have been destroyed by a large meteor last week. If intelligent life existed on a planet before impact with a large meteor, those creatures are either destroyed or technologically impaired after a relatively common collision. Not only travel but also communications to or from these distant planets is unlikely.
Even so, the sheer number of Earth-like planets, orbiting around distant stars, is so staggering that theorizing life exists on other planets is the most reasonable assumption. Based on Kepler space mission data, astronomers reported, on November 2013, there could be about 40 billion Earth-sized planets orbiting in the habitable zones around Sun-like stars and red dwarfs in the Milky Way. The Milky Way is a relatively small part of the universe.
Most likely, there is life on other planets; but if highly evolved space creatures discovered life on Earth they would conclude - due to the way humans treat other life and the planet - that there is no intelligent life on Earth. Which intelligent life form would really find a use for increasing polluted oceans, on a planet where people appear to be doing everything possible to accelerate Climate Change, while denying that it exists? Who wants to spend their precious time attempting to communicate with fools?
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