NASA Announces a Single Star is Home to at Least 7 Earthlike Planets
It may host our best hope for life in Space.
The galaxy is getting very crowded. There may be 300 billion stars in the Milky Way, but until just over 20 years ago, we only knew of one of them that was orbited by planets. In the years since, the galactic census has exploded, with more than 4,700 confirmed or candidate planets discovered so far and astronomers concluding that every star in the galaxy is parent to at least one world.
The new findings are the result of more than six years of study of the small star Trappist 1, located just over 39 light years from Earth — barely one town over in a galaxy that measures 100,000 light years across. The star got it’s name from a rough acronym of the telescope in the Chilean desert that has studied it the most. The telescope looks for planets by watching for the portion of their orbit in which they transit — or pass in front of their star, causing a tiny but dimming in starlight.
Three Earthlike planets were discovered around Trappist 1 in early 2016 using this method. That prompted the astronomers who made the find to bring in some bigger guns. Conducting more surveys with ground based telescopes as well as NASA’s Spitzer Space Telescope, they found 4 more planets. All seven , except the outermost one are closely grouped and all orbit at the right , cozy distance to sustain biology, at least theoretically. They think that they have liquid water and life of some kind.
If there is any life on any of the planets, it could be discovered relativity soon. Sending a spacecraft to visit is out of the question, of course.Even traveling at the speed of light , which is nearly 671 million miles per hour,,, the ship would take 39 years to make the trip. Instead, the hunt for life on the newly discovered planets will be conducted by both orbiting and Earth based telescopes, which will study the spectrum of T-1’sstarlight as it streams through the atmospheres of any of the planets during their transits. The closer that the chemical fingerprint comes to matching that of Earth’s atmosphere, the likelier it is something’s living on one of the other worlds. So if the 7 planets do not harbor life yet, they still have plenty of time. T-1 is very young,,, just 500 million years old, compared to our 4.5 billion year old sun. That makes our sun middle aged with only another 5 billion or so years left. Red dwarfs, as they are now being called, burn through their hydrogen fuel much more slowly.
Trappist 1 will live on for one thousand billion years.. If life is going to emerge in the system,,,, it has all the time it needs…
I doubt we will ever know,,,, but we can hope.