54
#14 Psr B1620-26 B – Almost as Old as the Universe
With an estimated age of 13 billion years, the planet is twice as old as Earth's 4.5 billion years. It's as old as a planet can be, in that it formed around a young Sun-like star just 1 billion years after the birth of our universe in the Big Bang , the ancient planet having a remarkable history because resides in an unlikely and difficult area. It orbits a peculiar pair of stars burned into the crowded core of a cluster of more than 100,000 stars.
#15 Kepler-438b – The most Earth-like planet in terms of radius and mass.
Kepler-438b has an Earth Similarity Index (ESI) of 0.88, the highest known for a confirmed exoplanet to date, making it currently the most Earth-like planet in terms of radius and mass. The planet was announced as orbiting within the habitable zone of Kepler-438, a region where liquid water could exist on the planet's surface.
#16 Wasp-17b – Moving in the opposite direction