By Mariam Malik ‘22

A planet is a celestial body that rotates around a star in an elliptical orbit. Separate from fixed stars, each planet has its own unique motion. New and combined research from multiple universities around the world shows the discovery of a new planet, NGTS-4b, which is smaller than Neptune but found in an area where most Neptune-like planets are not found, which may reveal information on the planet’s durability. 

At the European Southern Observatory’s Paranal Observatory, located in Atacama Desert, Chile, the planet was observed from August 2016 until May 2017. Researchers looked for any signs of transit-like signals when a celestial body moves across another celestial body. When a transit occurs, the planet moving across a star causes a decrease in the light of that star. Therefore, when astronomers are searching for new planets, they look for drops in the light of the star. 28 transits were recorded and the team also discovered that the new planet is located in the Neptunian Desert, a region of space near the stars where no planets the size of Neptune can be found. The Neptunian Desert obtains strong irradiation, causing an inability of planets to preserve their gaseous atmosphere. However, NGTS-4b still possesses its gaseous atmosphere. Researchers, such as Dr. Richard West of the University of Warwick, UK, believe that “The Forbidden Planet” must have entered the Neptunian Desert pretty recently, within the last one million years, or that it was once very large and its atmosphere is still evaporating. 

What is unique about the discovery of NGTS-4b is that it was found through a K-dwarf’s light dimming by less than 0.2%, showing the improvement and precision of space technology. After believing that most Neptune-sized planets do not survive in the Neptunian Desert, the discovery of NGTS-4b is noteworthy provides insights into other planets that may exist in the Neptunian Desert. 

References:

1. G. West, et al,. NGTS-4b: a sup-neptune transiting in the desert. Monthly Notices of the Royal Astronomical Society 486, 5094-5103 (2019). doi: https://doi.org/10.1093/mnras/stz1084
2. Image retrieved from: https://pxhere.com/en/photo/635208