Direct Detection In Planetary Research

For our lab presentations, Natalie Lutz and I chose to research other planetary systems. We knew this was a topic that would lightly be discussed in class and therefore decided we could educate our peers further on the topic. It offered a look into the different types of ways planetary systems are discovered and the different ones that have already been discovered. Extrasolar planets are defined as planets rotating around other stars- or remnants of stars. This is comparable to our planet rotating around the Sun. We have known for centuries that these other stars existed. Despite this, it wasn’t until the 1990’s that the first extrasolar planets were discovered (Bennett et al, 2016) In order to discover the planets, we must have ways of …show more content…
Direct detection is where astronomers obtain direct images of exoplanets. It’s very difficult for astronomers to detect this way mainly because of distance. The telescopes used today are not exactly as technologically advanced as needed but despite this some discoveries have been made. Since it’s rare for discoveries of exoplanets to be made with this type of detection, some astronomers fear that they are not truly exoplanets (Bennett et al, 2016). The indirect method is the more popular method for detecting exoplanets. The indirect method is astronomer’s way of detecting exoplanets without actually seeing the planet. This method has two approaches to it. Astronomers can observe the planets indirectly by observing the gravitational tugs on a star or they can observe the changes in a star’s brightness. Each approach has certain methods under them that are used to detect the star’s exoplanets (Bennett et al, …show more content…
This method is based on the motion of the star. Objects don’t just rotate around a star, they are actually rotating around a center of mass. This center of mass is created from each planet and the stars heavy masses. An astronomer will use this center of mass to their advantage. If they can observe that a star is seen “wobbling” around this center of mass, it is easy to assume that the cause of this is an exoplanet. The way they can observe if a star is seen “wobbling” is looking for small changes in a stars position in the sky. This is often difficult because it’s hard to see such little change in movement when we’re thousands of light years away, thus it requires many, many years of detection of the planets. This method is better suited for finding massive planets orbiting far from their stars. Despite being used the longest, this method has found few exoplanets (Bennett,