I’m pretty sure you’ve heard by now of the latest big discovery, that being four new exoplanets orbiting TRAPPIST 1, a star in the constellation of Aquarius. Aquarius is visible on the Northern Hemisphere, but TRAPPIST 1 cannot be seen with the naked eye.
TRAPPIST 1 is an ultra-cool dwarf star, at least 500 million years in age. That is a minimum age estimate, and in reality the star could be several billion years old. At about 8% Solar mass and 11% Solar radius, TRAPPIST 1 is likely to live much longer than our Sun.
TRAPPIST 1 is about 39,5 light years away. With our current methods it is of course unreachable, but I’m thinking this would be a strong candidate for my story. Three of the planets are within habitable zone, and assuming the have any sort of atmosphere they may also have water.
I suck at math, but from a few calculations I did last night (and probably botched), a generation ship could cover the distance in less than ten generations with even 50% light-speed. Now, for the sake of fiction that might be plausible.
So, the planets. Three planets were found already back in 2015, but now the team had more data and found four more planets. Even more new data will become available early this coming March (to the public on the 6th). This new data is by the Kepler telescope and spans over 70 days of observation. It might give new insight as to whether there are even more planets on orbit, what the planet masses are for the currently discovered planets and the orbital period of 1h. Also, Kepler takes observations on the overall brightness of TRAPPIST 1.
So, the three most interesting are the ones in the habitable zone, called 1e, f and g. 1e is about 0,7 Earth masses, f the smallest at about 0,6 and g the largest at 1,1. G gets about as much light from TRAPPIST 1 as the zone between Mars and the asteroid belt get from the Sun, f about as much as Mars. 1e is the most Earth-like, as it gets about as much light.
Even more new information can be discovered after the launch of the James Webb Space Telescope, scheduled to launch 2018. JWST is accurate enough to give readings on the gas composition of the planets’ atmospheres and the presence of water or other gases usually resulting from life (I say usually, because oxygen and ozone can also be created by chemical reactions or the star’s unusually high UV radiation). Among these gases are oxygen, ozone and methane. These readings will be available in about five years.
As TRAPPIST 1 is rather small, the planets are quite close together. This causes the planets to have gravitational impact with each other, which could also cause consequences on planet surface. The strength of the impact is dependent on the strength of the planets’ possible atmospheres. The positive side of this effect is that it allows the planets’ masses to be more carefully measured than otherwise.
The other negative effect are the solar flares. TRAPPIST 1 has flare occurrences weekly and bigger flares bi-annually. Unless the planets have magnetic fields they cannot resist the radiation and will most likely be uninhabitable.
SETI is observing TRAPPIST 1, but so far nothing has been received. It’s also been pointed out that due to the extreme distance the signal would most likely be static anyway.
Apart from these news I also discovered a couple interesting points I need to explore further in my story. I’ve been trying to figure out how I could make a generation ship work – how medical care skills, engineering skills and so on can be passed on as the first Earth-trained generation ages and dies away.
That’s the main issue: spare parts can be stocked up and the amount of fuel must be system-regulated and present at takeoff. The engines and other systems must be kept in operating condition through the journey, though, and the passengers must arrive in acceptable health and numbers to settle.
I have some solutions thought out, but I doubt none of the first-level solutions will be manageable all the way through. We’ll see.
So long for now, the Sun is shining and I’m going to enjoy that while it lasts.