So another week, another poem. One of these days I’ll actually pause and go back to re record my old poems with some wording changes and some actual editing to the videos, but today is not that day only in part because I had two midterms this week and am writing this at 4 in the morning. Regardless let’s talk poetry. “The Sun” was an interesting poem to write in that I had to balance my urge to pour out everything I know about the Sun with actually making this a poem and not a documentary. To prevent myself from giving into that temptation I decided to personify the Sun to a very high extent by talking directly to it. I have always loved story telling poems, so narrating the life of our Sun back to our Sun seemed like a cool challenge. The parts that I liked the most were right at the end when I talked about the dying of the Sun. So… while I have you here let’s talk about star life cycles.

As we do with all good stories, we start at the beginning. (For those interested I am pulling most of my information from this website to make sure I am getting my facts correct) We begin with a nebula. The source of this nebula is not completely known, but approximately 4.6 billion years ago the cloud began to collapse. The collapse caused dense regions to form in the dust and gas, which caused a chain reaction of gravity that pulled more in more matter. As the dust and gas coalesced it also began to rotate at an increasing speed (Conservation of Momentum). This rotation caused the matter to form a disc around a central ball that would become the Sun. The pressure caused by gravity on the ball generated heat that built up in the young protostar for around 100,000 years before igniting nuclear fusion in the core. The young star was a T Tauri star, a very active young star that releases intense solar wind. This stage did not last long (only a few million years, so no time at all). The Sun, now settled into it main sequence stage where it converts hydrogen into helium. From what we know about the Sun we can say it has been in this sequence for 4.57 billion years. Unfortunately, our Sun like all stars only has so much fuel and will inevitably run out. This process of burning fuel creates more pressure through a shrinking of the core and an increase in gravitational pressure, which in turn prompts faster fusion of hydrogen that increases the luminosity of our Sun by 1%… every million years. In 1.1 billion years, the Sun’s increase in energy will heat the Earth causing a greenhouse gas effect. By 3.5 billion years the Earth will be more like Venus than the planet we know and love. When the hydrogen eventually runs out, the helium in the core will collapse and the Sun will expand as the core heats up forming what is know as a Red Giant. THis expansion will eat Mercury and Venus with the potential of reaching the Earth as well (is being consumed by the Sun or completely scorched worse?) At this point the Sun will be in its death spiral. It will spend around 120 million years in the Red-Giant-Branch phase before suffering a helium flash. The Sun will shrink to around 10 times its current size (its still huge) and will be around 50 times its luminosity, but it will be cooler than it is today. A 100 million years from then most of its helium core will be gone and it will be in the Asymptotic-Giant-Branch phase where it again expands and becomes more luminous. This phase last for about 20 million years where it loses mass from thermal pulses, but grows larger and more luminous. The Sun will lose most of its mass and the exposed core will cool into a white dwarf that will fade to black.

So, I talked a lot, but space is cool and so is the inevitable heat death of the Universe. Regardless, the Sun is a pretty cool guy. (Well maybe not that cool)