Scientists on the planets are «dead» stars that might have life

© NASA/JPL-CaltechПульсар and its orbiting planet through the eyes of the artistScientists on the planets are «dead» stars that might have life© NASA/JPL-Caltech

Life could exist on the surface of planets orbiting pulsars, if the atmosphere has sufficient density to make the most of their x-rays and high-energy particles into heat, say astronomers in an article published in the journal Astronomy & Astrophysics.

«Our calculations show that the temperature at the surface of planets, shelled in a similar way, the pulsars will be high enough that water could exist in liquid form on the surface. On the other hand, we do not yet know whether planets orbiting pulsars suitable for this atmosphere,» said Alessandro Patruno (Alessandro Patruno) of Leiden University (the Netherlands).

In recent years, planetary scientists have discovered nearly two thousand planets outside the Solar system, almost all of which revolve around «normal» stars. Interestingly, the first exoplanets were discovered at «double» of the Sun or a red dwarf, and in the vicinity of the pulsar PSR B1257+12 in 1992 and 1994. Two more such planets were found near the pulsar PSR B1620-26 in 2000.

These planets, although similar to Earth composition and relatively small size, virtually was initially considered dead, scientists assumed that the powerful beams of x-rays and high-energy particle had to completely destroy life on the surface, if it existed. Even if the inhabitants of such worlds would somehow be protected from these problems, the process of formation of neutron stars a supernova explosion was supposed to completely destroy the atmosphere and any signs of life on their surface.

In recent years, as noted, Patruno, scientists have found that planets can be formed in the vicinity of pulsars after the death of a star from its «remnants» or fragments of the shells of her companion that made them wonder whether such worlds with atmosphere and if the most primitive life forms to survive on their surface.

Patruno and his colleagues Michel Kama (Mihkel Kama) from the University of Cambridge (UK) have checked whether this is in fact studying the properties of three planets orbiting PSR B1257+12. All these worlds are earth-like planets, and, as suggested by the astronomers, they might have atmosphere and significant water reserves.

The main threat to life on the surface, as the researchers note, are x-rays and high energy particles that will disperse powerful magnetic field «dead star». The power of this radiation and the number of particles, the astronomers measured, using data collected by the telescope «Chandra» during observations of PSR B1257+12.

As shown by these measurements, the power of this radiation and particle flux is quite modest for planets at a great distance from the «light», approximately 2 to 5 astronomical units, the average distance between the Sun and Earth could carry them.

To do this, however, requires that such planets have sufficiently large dimensions, «earth’s» magnetic field and thick atmosphere, preventing the x-ray and particles to reach the surface and prevents the rapid escape of water molecules into space.

In accordance with these calculations, the last two planets from PSR B1257+12, as noted, Patruno, located on the border of the «zone of life» — a special «bundle» of the orbits of the pulsar, where water can exist in liquid form due to heating of the planet under the action of x-rays and high-energy particles.

Scientists believe that this fact, given the existence of approximately 10 million planets of pulsars in the milky Way, suggests that potentially habitable worlds can exist in the vicinity of «dead stars».