Astronomers and physicists alike have long speculated that other stars must have planets that orbit them just as they do in this solar system. It is quite exciting to realize that such a consensus has turned out to be true. In the past couple of decades, advances in distant space observation by means of orbiting telescopes have revealed hundreds of such planets orbiting other stars. Moreover, some of these planets are now classified as “super earths.” However, before you read any further, it should be pointed out that the term “super earth” can be misleading.
At first guess, the lay person may assume that a “super earth” is just like this planet, i.e., a world teeming with continents, oceans, and a breathable atmosphere, except bigger. Disappointing as it may be, a “super earth” has very little in common with this planet. Exoplanets classified as super earths have masses around 10 times that of good old Terra Firma. But at the same time, such a planets’ mass will still be lower than that of Uranus or Neptune, hence the term, “super earth.” Such worlds are larger than earth, but smaller than the gas giants. Unfortunately, for any hopeful people out there, the term super earth has nothing to do with a planet’s surface characteristics.
However, a significant event took place in May, 2012. For the first time, astronomers detected light from a small, rocky body outside of this solar system. Back in 2004, a star known as 55 Cancri, located about 41 light years out in the constellation of Cancer, was found to have five planets. One of these planets is 55 Cancri e, which orbits at extremely close range to its parent star. The planet’s year lasts all of 18 hours as opposed to Mercury’s 88 days or Earth’s 365 days. Up until this time, exoplanets have been detected by observing a slight decrease in a star’s magnitude as one of these orbiting bodies pass in front of it. Another way to detect such planets is to observe an apparent wobbling of a star as a body orbits it. However, the Spitzer Telescope, launched by NASA in 2003, detected infrared light directly from 55 Cancri e itself. While this isn’t the first time such light has been found coming directly from an exoplanet, it is the first time such light has been detected from a super earth in particular as opposed to a “hot Jupiter,” which describes very large planets composed of gas.
Interesting observations from Spitzer have revealed that 55 Cancri e is very hot on the side that faces its parent star, with an estimated temperature of some 3140 degrees Fahrenheit (1726 degrees Celsius). In all probability, the planet lacks a sufficient atmosphere to warm its dark side. In addition, the planet is said to be oozing. It is believed that about 20% of the planet is composed of light elements including water, but a supercritical fluid state exists due to the extreme temperatures. Picture a surface that resembles oatmeal being overcooked in boiling water, and to add to the fun, some of that gaseous steam collects to form a liquid. That is what is meant by supercritical fluid. To summarize, 55 Cancri e is likely a rocky world immersed in volatile water and topped off with steam, so this place isn’t exactly what one would call a vacationer’s paradise.
NASA’s next major infrared space telescope will be known as the James Webb Space Telescope, and is scheduled for a 2018 launch. With the Spitzer’s discoveries, it is hoped that the James Webb Telescope will focus its attention and provide mankind with detailed information of more habitable worlds yet to be discovered.
