The time has come. The beginning of the end of our Universe. It is now 10 to the power of 14 years. Our Sun is ancient history in cosmic terms. It expanded into a Red Giant billions of years ago, swallowed the Earth and exploded in a supernova explosion.
Credit : National Geographic Magazine
At this point it is safe to say Earth is gone as we can currently measure the power output of the Sun and how long it will take to expand. Humans will only live to see and feel The Degenerate Era if we colonise other planets. I mentioned before, the Trappist-1 star burns at a much slower rate than ours. It’s life span will be approx 12 trillion years so it is possible inhabitants of that system will live during this period.
Dark Energy makes up 69% of the Universe. It drives the expansion and makes it accelerate. For every 32 million light years the Universe expands at 71km per second. So if you look 13.7 billion light years away with a telescope, galaxies are moving away from us faster than the speed of light! As our Universe expands, the less of it we will see. These galaxies will be accelerating away from us at such a speed that their light will never reach us.
Credit: Square Kilometer Array.
So can Dark Energy be overcome? The short answer is no. There isnt enough regular matter to rein it in and reverse the expansion. So in that regard, the Universe will expand forever!
At the beginning of the Degenerate Era all we will see will be white dwarfs – the cores of exploded stars, Brown/Red Dwarf Stars which burn at much slower rates and Black Holes.
Brown dwarf stars are much smaller and fainter stars which didnt grow to a sufficient mass to fuse hydrogen to helium like our star. Instead they are thought to fuse deuterium and lithium.
The Universe will have become a very dark place. Most other galaxies will have accelerated away from us and Astronomers born at this time, could easily assume we are the only galaxy that ever existed.
Unfortunately, these stars will not last forever either. Proton Decay will occur the left over stars. The matter from the Stars will slowly fade into smaller subatomic particles, making the stars much dimmer.
Credit : Dreamstime.com
A white dwarf fuelled by Proton Decay will generate around 400 Watts of power. Your microwave in your kitchen will generate more power than that but they will appear like a bright star looks to us now.
The planets orbiting these stars will slowly freeze. As the stars lower in mass, the gravitational force will weaken as the mass reduces. The Planets could escape the star’s gravity or be flung out if another rogue star drifts near the system. There will be significantly more Black Holes in the cosmos as the high mass stars that collapsed, never to be replaced.
The Black Holes will significantly disrupt any order within the few stars and planet systems at this time. This era will be frantic, chaotic and downright terrifying!
Eventually, all the remaining stars will have decayed. Imagine this, the last remaining star. The very last ultra cool low mass Brown Dwarf. If there is a planet orbiting this star with a humankind civilisation, they will live in fear knowing they are the only ones left. Hopelessly outnumbered by Black Holes.They could be living their lives one second and literally gone the next.
Credit : BBC.com
One day that star and planet will be gone. Kaput. No life left in the cosmos. Over a period of quadrillions of years. So that is the end of The Universe then? Not quite. Then we will enter The Black Hole Era.