Soon in space will be new, powerful telescopes. It’s time to think about what we should see in order to make the most of their potential.
The Kepler Space Telescope has allowed astronomers to the discovery of thousands of planets outside our solar system. Similar hopes are in the TESS (Transit Exoplanet Survey Satellite). His role will be to detect exoplanets using the transit method, or find drops the brightness of stars caused by a planet moving across the face of the star. The beginning of the mission is planned for 2017 years.
However, the search for planets where conditions exist to enable the origin of life will belong to the second modern telescope. James Webb Telescope, which the launch is scheduled for 2018, will have the opportunity to explore the composition of the atmospheres of planets similar to Earth during transit spectroscopy – this represents a significant advance on the road to a better understanding of exoplanets and the search for extraterrestrial life.
Due to time constraints and costs, which generates the use of such equipment, number and type of subjects planets must be carefully selected. That’s why astronomers from the University of Washington – prof. Rory Barnes, prof. Victoria Meadows and research assistant Nicole Evans – have developed an indicator of the extent to which a planet can promote life. “We created a method of prioritization on the basis of observational data. In this way, out of hundreds of possible destinations will be able to choose those whose best place to start research “- said Barnes.
So far, astronomers have focused in their quest for the so-called. ekosferach, less formally known as “Goldilock zones”, which places the space around the star on which the orbiting planet could be liquid water, and thus is the basis for the formation of life. However, this approach gives only signal zero-one: the planet or is in the zone conducive to life, or not. According to the assumptions made by researchers from Seattle to make an additional divisions at the same zone. The index takes into account many of the values that will ultimately give the number corresponding to a probability with which a given planet has a chance to maintain liquid water on its surface.
One of the variables is the content of the rocks (rocky planets – as they like Earth – they scored above), another – the variability of the orbital-reflective indicating the total amount energy the planet receives from its star. The higher albedo causes greater part of the radiation is reflected from the planet’s surface, and this results in its weaker expose and worse conditions to support life. The large eccentricity, in turn, makes the quantity of energy supplied to the planet varies depending on the position in orbit. According to Barnes, the planets closer to the inner edge of the habitable zone life should have higher albedo to cool the surface by the reflection of infrared wavelengths. On the other hand, the planet on the outer edges of the ecosphere would show a higher eccentricity, so as to be able to provide the necessary energy a planet to live near periapsis.
Barnes, Meadows and Evans qualified in this way exoplanet discovered in both the Kepler mission and its continuation – K2. By the way, they discovered that the best candidate for inhabited planets should receive from its star 60 to 90 percent of the energy the Earth receives from the Sun, which is consistent with current knowledge about the areas capable of sustaining life.
“The potential indicator will grow together with our knowledge of egzoplanetach, derived both from observation and theory” – recognizes Meadows. “This is an innovative step allows you to go beyond the two-dimensional ecosphere to create a flexible framework to set priorities for a wide variety of properties and the factors that affect whether the planet can support life.”
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