Photo: M. Kornmesser Observatory in southern Europe / Agence France-Presse
“Oumuamua” is spent in the orbit of Mars to the 1st of November and will cross in the vicinity of Jupiter in may 2018
A mysterious object rock with the shape of a cigar detected in October came from another solar system, an unprecedented observation, which was confirmed Monday by astronomers.
This detection opens a new window on the formation of other star worlds in our galaxy, the Milky Way, according to these scientists, the results of the data analysis published in the british journal Nature.
The asteroid, dubbed Oumuamua by its discoverers measure 400 meters long and its length represents approximately ten times the its width.
This unusual form is unprecedented among the approximately 750 000 asteroids and comets observed so far in our solar system where they are trained, according to these researchers.
Scientists have concluded, with certainty, to the nature of extra-stellar of this asteroid because the analysis of the data collected shows that its orbit cannot have its origin inside our solar system.
Astronomers estimate that an asteroid interstellar similar to Oumuamua going on inside the solar system approximately once per year.
But they are difficult to trace, and had not hitherto been detected. It is only recently that telescopes to monitor these objects are powerful enough to have a chance to discover.
According to these astronomers, this is anything unusual has traveled alone through the milky Way for hundreds of millions of years ago before moving into our solar system and continue on his way.
A strange visitor
“For decades we thought that such objects of another world could be found in the vicinity of our solar system, and now for the first time we have direct evidence that they do exist “, stressed Thomas Zurbuchen, deputy head of the scientific missions of Nasa, who funded this latest research.
“This discovery opens a new window to study the formation of solar systems beyond ours “, he estimated.
“It is a strange visitor from a star system very far away that has a form that we had never seen in our neighbourhood cosmic,” said Paul Chodas, director of the Centre for the study of objects moving near the Earth at the Jet Propulsion Laboratory of Nasa in Pasadena California.
Oumuamua, which means messenger in the hawaiian language, was discovered on October 19, with the telescope Pan-STARRS1 located in Hawaii who is tracking objects crossing close to the Earth.
Immediately after its discovery, other telescopes around the globe, including the Very Large Telescope of the european southern Observatory in northern Chile, began to observe the asteroid to determine the characteristics.
A team of astronomers, led by Karen Meech, Institute for Astronomy in Hawaii has found that the brightness of the object varied up to ten times the power then it turns on itself every 7.3 hours.
No asteroid or comet in our solar system knows of such magnitude in the variation of its brightness or such a ratio between the length and the width, they stress.
No water, no ice
These properties suggest that Oumuamua is dense and is formed from rocks and can also be of metal.
But it has neither water nor ice, and its surface has been reddened by the effects of cosmic radiation for hundreds of millions of years.
A few ground-based telescopes of great power continue to track down the asteroid so that it disappears quickly as you move away from the Earth.
Two space telescopes, Nasa, Hubble and Spitzer, the follow this week.
On 20 November, the object was traveling at a speed of 38.3 kilometres per second and was at about 200 million km from the Earth.
Oumuamua is spent in the orbit of Mars to the 1st of November and will cross in the vicinity of Jupiter in may 2018, before proceeding on the route beyond Saturn in January 2019 when he will be released from our solar system to take the direction of the Pegasus constellation.
The observations with large ground-based telescopes will continue until the asteroid becomes almost undetectable, that is, after mid-December.