We all have grown up with space being limited to only the planets in our solar system, the Sun, the moon and the stars. As we grew older, we came to realize that there is a lot more to our universe than we always thought. There is a whole cosmos outside our 9 planets; celestial bodies like exoplanets. Exoplanets are planets that orbit stars other than the Sun, several light years away from the Earth. The word ‘exo’ comes from a Greek term, which means outside and was first noted in the year 1977. According to astronomers, there are approximately more than 4000 exoplanets orbiting a star and around 1000 more that are waiting for confirmation.
Given below is a list of ten of the most unusual planets in the universe other than the planets in our solar system.
HD 209458 b
HD 209458 b goes by the nickname of ‘Osiris’, who was an Egyptian god that has lost a part of his body. It is an exoplanet that travels around the solar-type star HD 209458, 159 light years away from us in the Pegasus constellation. It revolves around a Sun that is approximately 6437376 km away. Astronomers believe that it is one of the only exoplanets found that has detectable carbon and oxygen in its atmosphere. Its radius is 7 million km or one-eighth the radius of the orbit of Mercury. What is weird about this exoplanet is that it is evaporating at a very fast rate, which have led scientists to create a new category called Chthonian planets.
Kepler 16 b
The next exoplanet in this list of unusual planets outside the solar system is Kepler 16 b. Previously known as Kepler 16 (AB) b, this extrasolar planet is a Saturn mass planet that consists of 50% gas and 50% rock & ice. It completes an orbit in a period of 229 days and what is wonderfully weird about it is that it orbits a binary star. This makes it a confirmed circumbinary planet (a planet that orbits 2 stars, not 1). Another interesting fact about this planet is that it is nicknamed Tatooine, after the home planet of Luke Skywalker in Star Wars.
Kepler 22 b
Roughly twice the size of Earth, Kepler 22 b is known as the New Earth. It is said to be one of the most promising findings of the Kepler Space Telescope in December 2011. Located in the Cygnus constellation, it is about 587 light years or 180 parsecs away from Earth. The temperature on the exoplanet is around 72-degree Fahrenheit and comes within the habitable belt of its star. Some scientists believe that Kepler 22 b may have a rocky center and is most probably covered in an ocean, just like Neptune.
PSR B1620 26 b
Unofficially nicknamed as the “Methuselah” & “the Genesis planet”, PSR B1620 26 b is an exoplanet in a circumbinary orbit (the first one discovered ever) located in the Scorpius constellation, 12400 light years away. It is the oldest known planet in the universe, formed 12.7 billion years ago, just 1 million years after the big bang. Interestingly, the 2 stars that the Methuselah orbits are in fact dead stars that are burnt out. In the beginning, scientists were confused whether to consider it a planet or a brown dwarf. In the end, they concluded that it was not rare and classified it as an exoplanet.
TrES 2 b
Orbiting the star GSC 03549-02811 in the constellation of Draco, TrES 2 b is located around 750 light years away from our solar system. It was discovered in 2011 as one of the darkest known exoplanets. It reflects only 1% of the light that hits its surface. It is often called as the coal black planet. It is still unclear what makes the planet so pitch black.
Kepler 452 b
Known as the Earth’s cousin, Kepler 452b’s discovery was announced by NASA in 2015. It is about 1400 light years away from here. It has almost 5 times the mass that of Earth. The star it orbits is a red dwarf with an orbit of 130 days. When it comes to the age of Earth 2.0, it is older than the Sun, born 6 billion years ago. However, a 2018 study implies that the exoplanet has still yet to be proven and must be considered a potential candidate until proven otherwise.
Proxima Centauri b
The next planet in our list is the closest exoplanet to the Sun, which is named Proxima Centauri b. It orbits in the habitable zone of Proxima Centauri, which is a red dwarf star, located only 4.2 light years away from Earth. It is roughly the size of Earth and is locked tidally to Proxima Centauri, just like the Earth is tidally locked to the moon. While life may be possible on Proxima Centauri b, it is being bombarded with a lot of high-energy radiation and the fact that it has a strong enough magnetic field to prevent it from being blown away, is still not known.
TRAPPIST 1f
Located 39.6 light years away from the Sun in the Aquarius constellation, TRAPPIST 1f is an exoplanet that orbits around the habitable zone of TRAPPIST 1. It is one of the four new planets observed from the Spitzer Space Telescope that orbits the TRAPPIST 1. The mass and radius of the exoplanet is almost the same as the Earth. It is a part of the seven wonders rocky planets that could potentially have liquid water.
GJ 504 b
This is probably the most interesting one. GJ 504 b or Gliese 504 b is a magenta pink jovian planet in the system of solar analogs 59 Virgins, approximately 57 light years away. It was discovered in 2013 using NASA’s Kepler space telescope. It is believed to be one of the youngest planets known, just a *mere* 100-200 million years old!
55 Cancri e
Dubbed as the “diamond planet” in the past, 55 Cancri e is an exoplanet discovered in 2004 by McArthur. It is equal to 8.63 times the mass of Earth, with twice its diameter. It was the first super-Earth that was discovered circling a main sequence star. It completes the orbit within 18 hours and is the innermost exoplanet in its own planetary system. It is also known as the ‘Hellfire Earth’ as its temperature measures around 4900 degrees Fahrenheit!