Can Life Survive the Death of the Sun?
As summer settles down and temperatures climb into the northern hemisphere, it is impossible to forget how the sun affects life on our planet. It is massively the source of all our light and our warmth, offering just enough to maintain the delicate climate balance that we appreciate. It is not a coincidence; Life on Earth has evolved under the influence of the sun and, given time, adapts to any change.
The adaptation to the whims of a star is however not a small task. The sun may seem constant day by day, but let time extend for millions, even billions of years, and things change – a plot. And it’s not always for the best.
For example, in its thermonuclear nucleus, the sun merges approximately 700 million tonnes of hydrogen into 695 million tonnes of helium each second. The five million tonnes missing are converted to energy (via everyone’s favorite equation, E = MC2). It’s enough energy, it turns out that To feed a star. If you like mind -blowing numbers, the sun produces 4 x 1026 Watts of power – 400 Billion of Watts Billions. In other words, the energy that our star emits in a single second is sufficient to satisfy the total consumption of humanity for about 650,000 years.
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It is also enough to warm our planet to its current comfortable climate. In fact, using certain basic principles of physics, it is possible to calculate mathematically how much the earth should be taken from the sun’s energy emission rate. This solar energy flows into space in all directions of the sun, and a small fraction (about half a mini-milliardème) is intercepted by the earth, heating our planet. The quantity of heating takes place is a bit complicated, depending on the real radiant flow of the sun, the distance of the earth and reflectivity, and more. Execute the figures, the average of the land calculated Today, the temperature is around –15 degrees Celsius, colder than the water freezing point.
Real The measurements of the temperature of the earth, however, give a much warmer average, about 15 degrees C. The difference exists because the greenhouse gases in the air essentially imprison the heat of the sun, warming the earth above the calculated temperature. This warming comes mainly from natural greenhouse gases, be careful, but we add about 40 billion tonnes of carbon dioxide to the atmosphere each year, considerably increasing the warming effect. Note that this increase occurred during the last century, a time scale far too short to see a change from the sun; The current climate change of the earth is all us.
But energy production by the sun changes significantly – over hundreds of millions of years. The helium created in the nucleus is inert; Consider it as “ash” of nuclear merger. He moved to the center of the sun, accumulating over time (at the rate of 695 million tonnes per second!). As it gains mass, it is also pressed by the enormous weight of the sun layers above, so it compresses. A fundamental law of physics is that the compression of a gas heats it, so even if the fusion rate is mainly the same, the nucleus of the sun is still warming slowly over time – which means that the sun itself becomes brighter.
If we therefore pass the clock forward one or two, we find a disaster. As the sun becomes brighter, it will first increase the temperature of the earth that we will lose all the water vapor in our atmosphere and then, finally,,, All the surface waters of the planet. Our oceans evaporate. This global desiccation fairly firmly plants a stop sign for all life on earth. However, if it is comfort, it will not happen for three billion years.
The reactions that take place in the heart of the sun become very complicated after this point, but the greatest effect is that the energy production of our star will eventually increase. All this energy will be thrown into the outer layers of the sun. When you heat a gas, it develops, so the sun will swell in huge proportions – 100 to 150 times larger than today. At the same time, its surface temperature will drop, it therefore becomes rough, even if it radiates energy 2,400 times stronger than it does. This transforms the sun into a giant red star.
The sun will be so large, in fact, that it will consume Mercury and Venus. The earth can escape this fate; Astronomers support themselves if the sun is expanding will reach the earth or not. In the current state of things, things don’t look good.
Even if the earth survives, it will not be pretty. The temperature of our planet will be around 1,300 degrees C, hot enough to melt lead. During the day, the rocks on the surface melt and the earth will be a world of lava. In addition to that, our planet will lose its atmosphere in space when it will also become hot.
Is there a way for the land to escape this fate? How are other planets?
To answer these two questions honestly and in order, they were asked: “not really” and “not well”. There is a slight suspension because as the sun expands, its solar wind becomes much more powerful – so much, in fact, that the sun loses a substantial amount of mass. This means that the gravity of our star will weaken and that the planets will migrate outwards, far from the central top of the solar system.
But it is not enough. Jupiter, currently with a temperature of –110 degrees C cold, will heat up to more than 300 degrees C. Its frozen moons melt and begin to boil. We will not find a sanctuary there.
If you want to even find a climate marginally of clement anywhere in this distant solar system, you may have to look at Pluto, which, at the time, will be about 50 times further from the sun than the earth. Its surface temperature will be about –10 degrees C. It is still cold, but remember the greenhouse effect: there is a lot of frozen methane and carbon dioxide on Pluto, so that these ice can spray and possibly provide sufficient thermal retention to make the small world at least somewhat comfortable, if not exactly habitable.
What then? It gets worse, if you can imagine it. The sun blows from its external layers and the nucleus is exposed to space, transforming into what astronomers call a white dwarf. Although incredibly hot, the nucleus has only the size of the earth, so small that it offers very little warmth to the planets. They cool again, ending up falling well below the freezing point of any biologically useful molecule.
If there are a minimum of good news here, it is because all this will not happen for several billion years. Who knows what humanity will look like by then or if we will always be there? If we are, well, more stars are born all the time, and they will also have planets. Packing and moving is never fun, but if your house is on fire, there is not much choice. Perhaps we can find other land where we can settle for one or three before this whole process starts again.
