WRITTEN BY PHYLLIS SHEN

Exoplanets are planets that exist outside of our Solar System that orbit other stars. Over 4,000 exoplanets have been observed by space telescopes thus far. Recently, many more exoplanets have been discovered and classified by Dr. Markus Mugrauer, an astrophysicist at the Friedrich Schiller University, using data provided by the Gaia space telescope, operated by the European Space Agency. These findings greatly benefit researchers who study astronomy because studying exoplanets allows them to compare and contrast our Solar System to other similar planetary systems and thus better understand our own Solar System. Mugrauer closely examined the host stars of 1,300 stars, each around 1,600 light-years away, through the Gaia space telescope. In addition, using the same telescope, Mugrauer also observed around 200 companion stars, which are other large stars that are often unseen by space telescopes but can be observed through its effects on the orbits of surrounding planets (Friedrich-Schiller University). These systems ranged from 20 astronomical units to 9,000 astronomical units wide. For comparison, our own Solar System is around 80 AU in diameter (Cornell University).

Mugrauer’s observations revealed the behaviors of exoplanets in relation to the evolutionary changes of nearby stars. The researcher compared stars of different ages, including Red Dwarfs, which are the youngest types of stars, and White Dwarfs, which are much older and have cores that have been burnt-out over time. The presence of exoplanets surrounding nearby White Dwarfs revealed that exoplanets can often survive the harsh conditions of existing near a dying White Dwarf. This suggests that the planets in our own Solar System may be able to exist for longer than previously believed. Continued observations of stars that are similar to that of our own Solar System as well as their relationships with surrounding exoplanets that are similar to Earth can provide more precise inferences regarding the future of our Solar System. In addition, Mugrauer also examined star systems with multiple stars affecting the gravity of the same nearby exoplanets. These systems contained stars that were located about five times farther from each other than average stary systems, making the frequency of stars in those systems much less than that of ordinary ones. The masses of the stars in these systems ranged from 8% of the mass of our sun up to 1.8 times the mass of our sun. This is a matter of particular interest to astronomers because the sizes and placements of stars affect the formations and orbits of surrounding exoplanets. This is due to the gravitational fields formed by the gravitational pulls of these stars. Using these new observations, Mugrauer plans to continue classifying different exoplanets and their behaviors due to the presence of surrounding stars within their star systems (Friedrich-Schiller University). 

Cornell University. (2019, January 29). What is the size of the Solar System? Retrieved from http://curious.astro.cornell.edu/our-solar-system/159-our-solar-system/the-sun/the-solar-system/219-what-is-the-size-of-the-solar-system

Friedrich-Schiller-Universitaet Jena. (2019, November 13). Distant worlds under many suns: Astrophysicist discovers numerous multiple star systems with exoplanets. ScienceDaily. Retrieved November 13, 2019 from www.sciencedaily.com/releases/2019/11/191113103726.htm.