Found! Solar system neighbour with Earth-like planets

This is what TRAPPIST-1f would look like, as imagined by an artist. As it is one of the outer exoplanets, it would be icy. Notice how the other exoplanets are visible in the sky (Image courtesy: NASA)

The search for life in outer space has come closer to a discovery with scientists finding a solar system like our own 40 light years away. The system consists of a star like our sun called Trappist-1 that has at least seven planets, of which at least three could contain some form of life. This is the first ever time seven Earth-sized planets orbiting (going around) a single star have been found, said US space agency NASA which made the announcement of the discovery.

Exciting discovery

The new star system is called Trappist-1, after the telescope Transiting Planets and Planetesimals Small Telescope (TRAPPIST) that was used to find it. In 2016, a group of scientists studying data from TRAPPIST announced that they may have found three planets around a star close to Earth. Further study led to the latest discovery that TRAPPIST-1 is a solar system much like our own with seven planets orbiting the star. Since these planets are outside our solar system, we call them exoplanets.


What do we know about Trappist-1?

  • The star at the centre of TRAPPIST-1 is much smaller than our Sun and is called an “ultra-cool” dwarf star. It is so cool in temperature that liquid water could survive in planets orbiting quite near it. In fact all seven of exoplanets found are closer to the star than Mercury is to our Sun
  • The exoplanets have been named Trappist 1b, c, d, e, f, g, h with 1b being the one closest to the star. TRAPPIST-1d, e and f receive approximately the same amount of heat energy as Venus, Earth and Mars respectively. Each of these three rocky worlds could have liquid water on its surface-a key ingredient for life as we know it.

What’s next?

In 2018, NASA will be sending up a new telescope called the James Webb telescope. The new telescope will check the planets for the presence of water, methane, oxygen, ozone, any of which could prove life exists. The Webb telescope also will study the planets’ temperatures and surface pressures, which are also indications on how ‘livable’ these planets would be.

The planets are so close to each other that people standing on the surface of one planet could gaze up and potentially see geological features or clouds of neighboring worlds, which would sometimes appear larger than the moon in Earth’s sky.

What’s a light year?

Three of the TRAPPIST-1 planets are most likely to have water on them, and the ones further away could be icy planets. (Image courtesy: NASA)
Three of the TRAPPIST-1 planets are most likely to have water on them, and the ones further away could be icy planets. (Image courtesy: NASA)

Distances in space are so vast that we measure them in light years, as light travels faster than most objects. A light year is the distance travelled by light in one year and is equal to 9.5 trillion kilometres. At 40 light years, TRAPPIST-1 is just right around the corner from Earth!