The belief of the astronomers is that the planets are tidally locked for the reason that they are near to the sun. This is the situation when the time it takes a body to orbit goes well with the length of one rotation on its axis.
The outcome is that the same region of the body frequently faces the object it orbits around.
The implication for the planets of the TRAPPIST-1 system is that a part of each body is persistently blasted with the heat of their sun, despite the fact that the other sides are forever in darkness.
The discovery of TRAPPIST-1 new solar system is a great discovery that has given us a hint that looking for a second Earth is not just a matter of if, but when? Nevertheless, we do not need to wait to discover some other Earth resembling planets. This is in view of the fact that TRAPPIST-1 system has provided about seven such worlds, and they are right in our sights. All that is required from the scientists now is to point their telescopes at it and watch!