I look at knowledge with a new wonder!
Centaur's alpha star system, just 4,3 light-years away from our solar system, has a planet with a mass similar to Earth's. Visible to the naked eye in the southern hemisphere, we now know that there is a world, new to us, one of the brightest stars in the sky.
What appears to be just a star to our eyes is actually a system composed of two Sun-like stars (alpha from Centaur A and B) that rotate around each other and, in a further outer orbit, the star Next to the Centaur, smaller and less bright, which runs around the other two. A stellar ballet.
The discovered planet revolves around the alpha of Centaur B. It was discovered through the 3,6 meter telescope at the La Silla Observatory in Chile, from the European Southern Observatory. A team of astronomers from the Astrophysics Center of the University of Porto, led by Xavier Dumusque, and other European colleagues, published their discovery in the October 18 issue of the journal Nature.
With current technology, it would take 40 years to reach this planet. The light from the alpha of Centaur B, which researchers examined, is the one the star emitted 4,3 years ago. Because the starlight we behold has to “travel” to us. The speed of light is finite, although it is too large for our steps (about 300 km/s), and what we see in the cosmic firmament is the past of the stars' lives. It takes forever to embrace the knowledge of the Universe.
Eight minutes is the time it takes for sunlight to reach dawn each day. Don't be late because you've always arrived like this. When life emerged from molecular courtship, sunlight also took eight minutes. A measly eight minutes compared to the nearly one billion years it would have taken cellular life to “emerge” around here.
And how did life “come into existence”? There are many hypotheses formulated by the life that studies this subject. What is more consensual is that the development of the first cells was preceded by molecular evolution, an abundant synthesis of the molecular building blocks that are common to life on Earth today. Evolution that started with mineral elements and other substances available and soluble in water, galvanized with energy from volcanic activity and underwater “chimneys”, atmospheric electrical discharges, ionizing radiation from the Sun and space.
Many of the substantive properties of life seem to flow from the “behavior” of the ancestral molecular systems that now constitute, downstream, cellular metabolism. One of the characteristics of life is cooperation between different cells, with a view to survival that would be impossible, or more difficult, without this cooperation.
American biochemists have discovered a cooperative interaction at the boundary between “inanimate chemistry” and what is postulated to have been the first biomolecules with self-replicating and self-catalytic capacity in the history of life. Ribonucleic acid (RNA) molecules – one of the nucleic acids in cells and viruses today (the other is the DNA of our genes) – when mixed in the laboratory, interact in a network and sequentially in a very dynamic and cooperative way. This system of RNA molecules “has been shown to be able” to grow faster than other molecular systems with uncooperative autocatalytic cycles. This work was published in the same issue of the journal Nature indicated above.
These experiences illuminate the hypothesis that cooperative systems have advantageously preceded life on Earth itself! In fact, by cooperating we achieve what we alone cannot or take longer to achieve. That's the way it is with life, it's like that with the astronomers at the European Southern Observatory, and in general with all of us.
Antonio Piedade
Science in the Regional Press – Ciência Viva
Articles Reference:
Xavier Dumusque, Francesco Pepe, Christophe Lovis, Damien Ségransan, Johannes Sahlmann, Willy Benz, François Bouchy, Michel Mayor, Didier Queloz, Nuno Santos, Stéphane Udry. An Earth-mass planet orbiting α Centauri B. Nature, 2012; IT HURTS: 10.1038 / nature11572
Henning Tidow, Lisbeth R. Poulsen, Antonina Andreeva, Michael Knudsen, Kim L. Hein, Carsten Wiuf, Michael G. Palmgren, Poul Nissen. A bimodular mechanism of calcium control in eukaryotes. Nature, 2012; IT HURTS:10.1038 / nature11539
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