7 Things You Need To Know About Our New Planetary Neighbor: The TRAPPIST-1 Solar System

In May of 2016, researchers led by Michaël Gillon, an astronomer at the University of Liège in Belgium, announced that three rocky planets had been found orbiting a small red dwarf star called TRAPPIST-1. Over the following year, this research continued until finally the team published their results in the journal Nature that there are actually seven planets, and three could support life. Here are seven questions and answers you may have about this astounding new discovery.

Red dwarf stars are very cool-temperature, very small stars. Often, dwarf stars form after a larger star dies in a supernova and its core and other remnants form a new, smaller, colder star. However, red dwarf stars are not post-supernova remnants and are simply regular stars that just happen to be smaller and cooler to start with. TRAPPIST-1 is a particularly small red dwarf, only a little larger than our solar system's planet Jupiter.

Of the seven planets in the TRAPPIST-1 solar system, there are three that exist in an area called the habitable zone, or more amusingly, "the Goldilocks zone," meaning that their temperatures are most likely to be neither too hot nor too cold to support the existence of liquid water and therefore, possibly, life. Of these three, the most likely of all is TRAPPIST-1f, the most central planet. Here, you can see a diagram illustrating TRAPPIST-1's planet order:

First of all, all the planets are rocky like the inner planets of our solar system, like Earth. Second, hopefully, these planets would have liquid water on their surfaces, maybe even whole oceans. Planet F, which has the highest likelihood of habitability, is projected to be a little colder than Earth as a whole, but still has plenty of potential for water. The light of the planets would be 200 times less bright than the light the Earth gets from the sun and would also be pinkish or salmon-colored due to the red color of their star. Their star would also look three times larger than the sun does from the Earth. Looking out from the surface of one of the planets, you would also be able to see the other planets in the solar system, some as large as we see our moon since they're located so close together.

TRAPPIST-1 and its planets are located 40 light-years from Earth. That means that if we were able to travel at the speed of light, which we are not yet anywhere near figuring out how to do, it would take us 40 years to get there. However, the close location means that what we now see through our telescopes was happening in the TRAPPIST-1 solar system only 40 years ago, a pretty short amount of time by astronomical standards. So, while we are probably not going to be able to visit, we can study it very closely.

We don't know! If one of the planets can support water, it can support life, but we have no idea of knowing how life might evolve there or if it could at all. We don't know how advanced life would be. It would be thrilling to discover something as small as a microorganism, but figuring out if they have liquid water is the first and most important step.

Although we think of radio waves most often in terms of carrying sound, they're actually a form of electromagnetic radiation, meaning that they travel at the speed of light. Since TRAPPIST-1 is 40 light-years away, that means that if we shot a message out toward TRAPPIST-1 via radio waves, they would hear us in 40 years. If they were able to reply, it would be another 40 years before we would hear back. You're looking at about 80 years total to confirm contact if there happened to be intelligent life there with the means of receiving and responding to our message.

For the next decade, the scientists who discovered TRAPPIST-1 and its planets will be focusing their attention on planets e,f, and g, trying first of all to ascertain whether liquid water exists there and second to determine exactly what their atmospheres are made of. Other scientists will probably try to find even more red dwarf solar systems which may exist even closer than TRAPPIST-1.

Now, put your new TRAPPIST-1 knowledge to the test with our quiz!

And now that you've proven your planetary prowess, we want to know what you think!