The recent announcement of the discovery of the hottest yet planet determined specialists to turn their attention to other, equally extreme space bodies. As humanity continues exploring the solar system, it seemingly also finds new, bizarre and unexpected planets, and the wonders will most likely keep appearing. As it is, specialists released a list of the seven most extreme planets currently know.
Extreme Planets, Either Very Hot, Too Cold, Or Very Big
The recently discovered KELT-9b is presently considered as the hottest exoplanet. Observations revealed its star host, KELT-9, as being some 2.5 times more massive than our Sun. Its surface temperature was measured at reaching almost 10,000 degrees Celsius. KELT-9b, on its own, is a Jupiter-type of gas giant with a surface temperature of 4,300 degrees Celsius.
Specialists offer, in contrast, OGLE-2005-BLG-390Lb, which is the currently coldest planet. Believed to be a rocky star, it has a temperature of only 50 degrees above absolute zero or minus 223 degrees Celsius. Its host star itself is a cool, low-mass star known as a red dwarf.
Planet DENIS-P J082303.1-491201 b has the honor of being the most massive planet known at the moment. NASA’s exoplanet archives state that this has 28.5 times the mass of the gas giant Jupiter. Its great size is still causing debates as to its classification. Some are wondering if this shouldn’t be considered a brown dwarf star, just as its host.
Kepler-37b is the currently smallest exoplanet ever discovered. It is smaller than Mercury and just slightly larger than the Moon. Its closeness to its host star also makes it too hot to support liquids or life.
Planets can Also Be Very Young, Extremely Old, or Have Incredible Weather Conditions
The unenviable title of the planet with the worst weather goes to Venus. Although about the same size as Earth, this is covered by sulfuric acid clouds, with an atmosphere moving faster around the planet than its own rotation speed. With an atmosphere made up of mostly carbon dioxide (95 percent), and some 100 times denser than that of Earth, Venus hosts some hellish temperatures, of over 462 degrees Celsius.
The currently oldest planet is titled PSR B1620-26 b and is believed to be some 12.7 billion years old. As our Universe is considered to have 13.8 billion years, this planet is ‘just’ a billion years younger. It is also a gas giant, with a mass 2.5 times that of Jupiter.
In contrast, the youngest known planet is just around 2 million years old. Called V830 Tauri, this gas giant currently has three-quarters of the mass of Jupiter but is most likely still growing. It is acquiring more mass through its frequent collisions with other space bodies, such as asteroids. This also makes it quite an unsafe companion to be around.
This list of the seven most extreme exoplanets was developed by Christopher Schroeder, a lecturer at the University of Sterling’s Environmental Science and Planetary Exploration. As some point out, this list can also change as humankind discovers yet other space bodies.
Image Source: JPL/NASA