On Wednesday, February 22, 2017, NASA announced its discovery of seven planets orbiting a cool dwarf star 12 times less massive than the sun. This planetary system is a mere 12 parsecs, or 39 light years, away from us. This is a HUGE discovery for a few reasons, which I'll outline below. First, let's look at the actual discovery.
What Is the Trappist-1 Planetary System?
As I mentioned above, Trappist-1 is a planetary system located 39 light years away from our Solar System. (That's just 351 trillion kilometers away, by the way.) It comprises seven planets of rocky composition that all orbit the star known as Trappist-1A.
Through careful observation astronomers have determined that the seven planets have similar sizes and masses to Earth, and their orbital periods (the time it takes for them to revolve around the star) range from 1.5 days to 12.35 days. So for one of the planets one year is achieved in 1.5 days and for another one year is 12.35 days.
In addition, the planets may be tidally locked to Trappist-1A, meaning that the same side is always the daytime side and the same side is always the night time side. This is because the planets are so close to Trappist 1-A that its pull keeps them locked.
Why Is the Discovery of the Trappist-1 System Important?
The discovery of the seven planets orbiting their sun in the Trappist-1 system is legendary for three main reasons. Two are the actual scientific significance and the third is my own reasoning.
1. The Trappist-1 Planets May Support Life
NASA has confirmed that three of the planets orbiting Trappist-1A are firmly in the habitable zone of the star, meaning that the planets can support liquid water given the right atmosphere. And of course, where there is water, they may very well be life. But the astronomers who made this discovery also believe that there could be liquid water on any of the seven planets given the right conditions.
This is the closest we have ever come to ascertaining whether there is life on another planet outside our Solar System.
As Thomas Zurbuchen, the associate administrator for the Science Mission Directorate at NASA stated: "The discovery gives us a hint that finding a second Earth is not just a matter of if, but when."
2. The Trappist-1 Planets Are the Most Such Planets Ever Found Around a Star
To date, there have been more than 3,400 exoplanets discovered in nearby star systems. However, the Trappist-1 system is unique because it is the most planets ever found orbiting the same star and as a result the most planets found that could potentially support life. They are also relatively close to us so that astronomers can continue observing them.
The telescopes the astronomers are using will be able to measure any gases in the atmosphere to see if they are similar to the gases in Earth's atmosphere. The presence of similar gases would pretty much seal the deal in terms of alien life on those planets.
3. The Trappist-1 Planets Represent Human Achievement and Unity
My own personal joy in this discovery comes from the fact that it is the culmination of many people working together and is a great step forward for humanity. I’m overjoyed that there is a group of us who have dedicated themselves to space exploration. I see it as the worthiest of goals and maybe, just maybe, looking up will give us perspective, get us out of our own drama and perhaps even unite us. Of course, it is important for scientific reasons to continue space exploration, but I believe it is just as important for humanistic reasons, as I mentioned in my post on Breakthrough Starshot.
You know, in Star Trek the rule of first contact, that is, making face to face first contact with an alien race, is that the race must have achieved warp speed (which is faster than the speed of light) before first contact is allowed. It is part of the Prime Directive. This is because in the Star Trek universe it is understood that once a race achieves that level of technological advancement, they are emotionally/psychologically/mentally ready for contact with aliens. Pre-warp civilizations are deemed not yet ready for such a development.
If we continue our space exploration, constantly improving and innovating our technologies, then maybe, just maybe, we will be ready for first contact one day too.
If you'd like to know more about this amazing discovery and the Trappist-1 planetary system, here are some helpful links:
- Trappist-1 Official Website.
- Journal article in Nature.
- The New York Times article.
- Another NYT article.
Also, if you'd like to learn more about the 3,400+ exoplanets already discovered, here is the Open Catalogue of them!