In the constellation of weights, astronomers have found a unique ekzoplanetu, which is the light of the known planets located outside the solar system. It is heavier than the Earth is only two times, while most other ekzoplanet have much greater mass. The opening was made by an international team of astronomers using the 3, 6-meter telescope at La Silla (Chile). Planet, called Gliese 581 e, revolves around the red dwarf Gliese 581. Gliese 581 e interesting by the fact that, like predecessors Gliese 581 c and Gliese 581 d, rotating around the same star, is located in the so-called Fit for the zone. It is located not too close to their stars, and not too far away, just so that water could exist on it in the liquid state. The opening of this planet is no accident. Previously, scientists could only detect planets with masses of roughly the same as that of Jupiter. But recently they have developed new methods and tools that allow the planet to find the dimensions of the Earth. According to astronomers, the opening of Gliese 581 e is another significant step towards finding a double earth. The scientists suggest that Gliese 581 e may be not only a stony rock, and ice. According to the officers of the Geneva Observatory, Professor Mayor, opened the planet is the first candidate for the emergence of a new class of so-called planet-the oceans, which are entirely covered with ocean. The American Organization of NASA has recently launched its new Kepler telescope, which was created specifically for the study of planets, similar in size to the Earth. Their method of searching will be different from that offered employees HARPS/La Silla. There are currently active on the creation of a new generation of telescopes, which will be detailed to examine ekzoplanety with dimensions around the Earth.