A research team says the TRAPPIST-1 planetary system — a compact system of at least seven exoplanets with sizes similar to Earth — formed between 5.4 and 9.8 billion years ago. This is up to twice as old as our own Solar System. This illustration shows what the TRAPPIST-1 planetary system might look like from a vantage point near TRAPPIST-1f (at right). Image credit: NASA / JPL-Caltech. TRAPPIST-1 is an ultracool dwarf star in the constellation...
