Astronomers have caught an anomaly in their hunt for earth like planets. For the first time ever, they managed to observe a planetary system that has seven earth sized planets orbiting around a star. The star is tiny and dimly lit but many of the planets are supposedly capable of supporting life, according to the preliminary studies.
Situated about 39 light years away, the exoplanets circle the star and have majority of the requisite factors for a planet to sustain life. The fact that this planetary system is just 39 light years away is probably its second biggest attraction point. Instead of looking for evidence of alien life on our planet, looking elsewhere for the same is a better bet and that’s exactly what our scientists and astronomers have done. The star with these earth like planets is the TRAPPIST-1.
Now that the planets and the solar system has been discovered, expect a lot more information gathering over the next few decades. As time goes by, we should have more credible information on the probability of life on either of these planets.
Odd Planetary System
The star of this system isn’t your typical Yellow gaseous giant like our Sun. Instead, it is about 2000 times dimmer than the sun and is a dwarf star. Think of it as the size of Jupiter.
It was observed by a team operating an instrument at La Silla Observatory in Chile, which is called the TRAPPIST or Transiting Planets and Planetesmals Small Telescope. This explains the nomenclature of the star.
During observations, the TRAPPIST 1 exhibited multiple regular dimming events and this was initially accredited to three planets passing over the face of the star. Then in May 2016, the discovery team announced the existence of these three planets. All three planets were finalized to be the size of earth and categorized as possibly life sustaining by size and weight.
As further studies were conducted worldwide on this system, the odd transit of a few planets were questioned and because of this further evidence of more planets came forth. The transit of the visible planets and the dim star together pointed to the fact that there were more than just three planets. To further expand our understanding of the TRAPPIST 1 system, NASA spent three weeks on its Spitzer Space telescope during September through October 2016 analyzing the system. It was during this intense scrutiny that the final planet was declared to be actually total of three more worlds than initially thought taking the total count up to 7 planets along with 2 more exoplanets spotted by Spitzer.
All seven of these worlds are the size of earth with the smallest planet being around 75% the size of our own Earth and the largest just 10% greater in size and mass. The reason for such excitement is the discovery of not one but total of 7 planets in a single system that are similar to Earth. Typically, the number ranges between 0 to 3 per system but no more.
The seven planets all take up a strict orbit close to the TRAPPIST-1, closer than Mercury has with the sun. Because of this, it is believed that the inner most planet has an orbit that spans just 1.5 days at the very least and 12.5 days at most. In contrast, the outermost planet takes just 20 days.
More research shows that the six planets closest to their star are in near-resonance. This basically refers to their orbital periods being related with each other by just a couple of integers. Such an arrangement of planets occurs only when planets migrate closer to their stars over time. Unfortunately, at the time it is hard to figure out the complete composition of each planet beyond the fact that they are all rocky.