Madrid, 29 feb ( EFE).-International team of astronomers, with Spanish participation, has tried to land a new technique to determine signs of life on other planets, a method that analyzes terrestrial light reflected on the Moon and dealing of overcome the difficulties posed by conventional techniques.
The results of this trial, in which participated the Canary Islands Astrophysics Institute (IAC) are published in the journal Nature.
The key of the work has been studying the Earth as if they were on a planet outside the solar system and observe not directly, but through reflex projected onto its satellite, the moon.
The team investigated the phenomenon with the telescope of long-range (VLT, by its acronym in English), located in the Atacama desert (Chile).
The sun shines on the Earth and this light is reflected at the same time on the lunar surface; the satellite, therefore, acts as a large mirror that returns the land to us, light explained the researcher from the European Southern Observatory and main author of the work, Michael Sterzik, according to a release of the IAC.
Researchers have tried to find indicators such as for example certain combinations of gases in the Earth’s atmosphere, believed to be signs of organic life (the simultaneous presence of methane, water vapour and oxygen implies a biomarker of life).
In contrast to previous research, the new technique explodes polarization.
When the light is polarized its magnetic and electric fields have a fixed orientation (waves vibrate in a specific direction).
That have measured the researchers in this work is precisely how polarized light depending on the surface above reflected, explained to Efe Enric Pallés of IAC.
Is that, depending on whether it is ice, clouds, land or ocean surface, the reflected light is polarized in a degree and certain color.
The Group analyzed the light reflecting the Earth on the moon as if it were the first time they saw our planet and that light told them that the Earth’s atmosphere is partially cloudy, that part of its surface is covered by oceans, and other “especially crucial information”: that there is vegetation.
Scientists could even detect changes that occur in the land cloud cover and the amount of vegetation in different parts of the planet (everything with the reflection on the Moon).
This new form of search for extraterrestrial life is to overcome the difficulties posed by conventional methods: the light of a distant Exoplanet is very difficult to analyze because it is overshadowed by the powerful radiance of the star that illuminates.
For Stefano Bagnulo, researcher at the Armagh Observatory (United Kingdom), “is comparable to observe a grain of dust with a powerful light bulb”.
However, the reflection of the planet on its satellite is polarized (oriented in one direction), thus enabling your analysis easily through technical polarimetric (separate polarized light of which it is not).
From the headquarters of the southern European Observatory (ESO) in Garching, to the South of Germany, experts told Efe in Berlin that this finding can contribute to future discoveries elsewhere in the universe.
“If it exists, finding life outside the solar system depends exclusively on having appropriate techniques”, said Palle, who pointed out that these techniques could be applied in telescopes in ten or twelve years.
In his view, this work is an important step to achieve that ability: “the espectropolarimetrÃa will make easier the detection of biomarkers in the surface of a planet”.
The team admitted that this new “method will not showcase data on green midgets or intelligent life, but its application in the new generation of more powerful telescopes could easily give mankind the news that there is life beyond its planet,” concluded the IAC. EFE
ngg/egw/jcb/ik/Nablus
