WATCH | NASA held a press conference on its recent discovery.
New life in the search for inhabitable planets
A newly discovered solar system consists of Earth-sized planets that could contain life, NASA announced Wednesday.
The seven planets are 40 light-years (235 trillion miles) away and orbit around a star called TRAPPIST-1, an ultra-cool dwarf smaller than our solar system's sun. The three planets in the center of the series are in the habitable zone of their system, meaning they're far enough away from their sun to facilitate water and life as we know it.
The TRAPPIST-1 solar system is the first found to contain three Earth-sized planets -- technically called exoplanets since they are not of our home solar system -- existing in an inhabitable zone of a system around a star. And with seven Earth-sized planets total, it has the most Earth-sized planets of any system discovered.
It's named after the TRAPPIST ground telescope in Chile that discovered its first two planets in 2016. NASA's Spitzer space telescope found the other five planets after.
Planets "e" through "g" are in the habitable zone, NASA said.
The planets are Earth-size. Are they Earth-like?
NASA believes the seven newly discovered TRAPPIST-1 exoplanets are rocky, like Earth, and three of the seven (planets 1e, 1f and 1g) are at the proper distance from their star to be the right temperature to potentially keep surface water from either permanent evaporation or a frozen state.
Studies moving forward, NASA hopes, will try to determine whether, beyond being water friendly, these three exoplanets actually do harbor water.
How are they not Earth-like?
Since the TRAPPIST-1 star is smaller and weaker than the Earth's sun, its planets are much closer in orbit to it, and also much closer in orbit to each other. While standing on one of these planets, its closest neighboring Earth-size planet would appear in the sky larger than the Earth's moon, NASA said.
These planets are also tidally locked, which means they orbit their star with one side of the planet permanently facing it and permanently locked into daylight.
When are we flying over to scope out TRAPPIST-1?
As for one of the habitable TRAPPIST-1 planets serving as a nice place to escape Earth's current or future dangers, you should know that the system's 235-trillion-mile distance from Earth puts it a million times farther away than Mars. With SpaceX's latest calculations estimating a flight to the Red Planet as anywhere from one month to three months long, the limits of rocket power and the human lifespan mean there may never be a manned jaunt to, say, TRAPPIST-1f.
This is the most exciting result I have seen in the 14 years of Spitzer operations ... More observations ... are sure to reveal more secrets.