The Fourth Satellite: Less Pluto

In the dark Pluto family addition: another satellite. A small body that has received a temporary index P4, found almost by accident.

For dwarf Pluto, which the new classification does not apply to the planets, and includes a separate family (read: “Now – Plutoid”), was discovered by satellite is the fourth – and youngest. Its diameter is estimated at 13-34 km, which is much smaller than Charon (1043 km), no one Hydra (32-113 km). It is not surprising that enormous distance – the distance between the orbits of Earth and Pluto is several billion miles – so far remained unnoticed P4 satellite.

“It is remarkable that the Hubble telescope has allowed us to consider such a tiny object from a distance of more than 5 billion miles, and so clear” – sums up one of the authors astronomer Mark Showalter finds (Mark Showalter). Observations Showalter and his colleagues carried out within the framework of New Horizons, an ambitious project NASA, which should culminate in sending long-range space missions to explore the surrounding area of ​​Pluto and even further – to the Kuiper Belt. If the satellite P4 has not been identified, it is difficult to imagine how the future was coming to New Horizons probe to Pluto.

P4 orbit lies between the orbits of Nix and Hydra, as observed recently in 2005 (close-Charon was discovered in 1978). Experts believe that the whole system of satellites of Pluto was formed as a result of its collision with another celestial body, which is comparable with the size, even at a young age the solar system. It is also assumed that the frequent strikes have micrometeorites strike the surface of Pluto’s small amounts of a substance that can form around a thin ring of the planet. That is what the ring tried to consider the astronomers using Hubble – but saw only companion.

For the first time P4 was found on a photograph taken Telescope on June 28. The find was confirmed in a series of subsequent images 3 and July 18. In previous observations of Pluto, he remained undiagnosed, believed to be due to less exposure. I wonder what a sad name will result in a new satellite. Recall that Pluto itself is named after the Roman ruler of the underworld, Charon – the carrier of souls across the river of oblivion, no one – the goddess of the night, and the monstrous Hydra needs no introduction. The last in this dismal company is rumored to be Cerberus.