Astronomers have discovered an exoplanet that is around 13,000 light-years from Earth, making it the most distant planet ever found. Though, it is not an astounding discovery because of the exoplanet itself, but because what it means for the future of planetary studies and mapping.
NASA astronomers used the Spitzer Space Telescope and the Optical Gravitational Lensing Experiment (OLGE) to find the distant exoplanet, which has been named OGLE-2014-BLG-0124L. Besides its confusing name, not much else is known about it other than the fact that it is categorized as a gas giant – one half the size of Jupiter. The exoplanet is located in the Milky Way; not far from Earth, cosmically speaking. Although astronomers have found around 1,800 exoplanets and nearly 5,000 other possible rocky bodies, it shows how much more space in the galaxy is yet to be observed and studied. When engaging in the search for exoplanets, astronomers use three methods: the transit method, gravitational microlensing, and direct observation and imaging.
The transit method is one of the most commonly used methods in planetary science. Astronomers discovered the first ever found exoplanets by locating a possible host star. Then, when the planet crosses in front of the host star, the brightness decreases very minutely. Therefore, if the distance to the star from Earth is measured, as well as the relative sizes of the planet and the star, they can confirm the have found an exoplanet with a stable orbit.
When reaching out to far away exoplanets, like the one discovered 13,000 light-years from Earth, astronomers use a technique called gravitational microlensing. The massive gravitational pull of a host star acts like an optical lens that magnifies the light coming from a star in the background of view. If there is a planet in the area, it will affect the visual results in a very small, but still observable way.
With current telescopic technologies, direct observation and imaging is by far the toughest for astronomers to conduct. For example, the first exoplanet discovered using this method was found just six years ago. When using highly advanced imaging, the planet is typically in its infancy, emitting wavelengths of infrared light. It is far enough away from the star that the glare does not hinder the image.
Finding exoplanets is an extraordinary discovery. Though, finding those in the “Goldilocks zone” are even more remarkable. The Goldilocks zone is the area in which an planet is close enough and just far away from its host star that liquid water is present. Just as the Earth is 93 million miles from the Sun, it sits just within the region that the planet does not bake or freeze. Finding exoplanets in the Milky Way Galaxy, especially within the Goldilocks zone, gives astronomers hope that they will be able to locate a planet that may harbor extraterrestrial life. Although they have not found out if the planet they discovered 13,000 light-years away is within the Goldilocks zone, they will continue to use methods of planetary observation to find if it may be a habitable place.
By Alex Lemieux
Photo by Bill Lile – Flickr License