Ever since Galileo pointed his telescope to the stars and discovered whole planets, humans have been fantasising about colonising other worlds. While in our own solar system, the likelihood of creating a “second earth” is unlikely, chances are there are thousands, if not billions, of life-sustaining planets out there with similar earth-like qualities. The trick is to find them.
This is a task that scientists have been eagerly working on in a bid to find theoretically inhabitable planets in case things take a turn for the worse here on Earth. Judging by the way we are destroying the natural resources and the rate of climate change, we might need to vacate our planet sooner than we think. The good news is that NASA and a group of international scientists are already finding potential candidates.
How to Find a Planet in a Haystack
To date, there have been 30 confirmed discoveries of exoplanets that are thought to be relatively close in size to earth, and potentially capable of sustaining life. The term exoplanet refers to a planet outside our own solar system and one orbiting a star. Recently a group of scientists have discovered another 20 potential planets that could be added to the list to make up at least 50 possible candidates for our eventual exodus.
How and when we are going to travel to these distant worlds is another problem for another time, but for now we can focus on finding and confirming a potential new home while doing everything we do here; from going out for dinner to playing at an online casino, to studying or going to work can be done.
So how does one go about finding a planet millions of light years away, which is supposedly capable of supporting human life? The first step is to find a planet that is not too small, not too big and has the perfect orbit duration. This is the time it takes for the planet to travel around its star (sun). In our case, it is around 365 days.
The Kepler Telescope
To do this, scientists use light sensors to measure the point where the planet blocks out a bit of the sun’s light. When the planet comes around again (completes its orbit), it will dim the light to the exact same reading giving us an idea of its solar orbit. In 2009, the space telescope Kepler was launched to do just this job. While it broke down in 2013, over the four-year period it was in operation, it recorded an area of space containing over 150 000 stars.
Scientists whittled down the list of exoplanet candidates to around 4000 with orbits of between 6 hours and 632 days. Of the 4000 odd planets, the team singled out just 20 planets that have the potential to sustain human life. One planet in particular has been causing a ripple of excitement through the astronomical community. Planet KOI-7923.01 is apparently 97% the size of earth and it has an orbit of 395 days; just a few more than what we are used to.
In terms of gravitation force and seasons, it will be a very close match to earth. It is thought that the surface of the planet is cold tundra, but not so cold that it will freeze all liquid water or be unable to sustain life. If there was one planet so far that we could potentially send an “Interstellar” style mission to explore, it would be KOI-7923.01.
While the scientists are reasonably confident about their findings and their evaluations, the next step is to make conformations about their habitability by pointing the Hubble Telescope at them or by studying them with ground-based instruments. The idea is that if, by the time we create interstellar travel, we will have a good idea of where to go!