What is an exoplanet?
As NASA states, “An exoplanet is any planet beyond our solar system...” Therefore, it seems quite difficult to discover a new exoplanet as it demands to acquire knowledge of the characteristics that define an exoplanet and proper guidance.
How many exoplanets exist and being discovered?
According to NASA, more than 4,000 exoplanets have been discovered and are considered "confirmed". Since the first exoplanets were discovered in the early 1990s, the number of known exoplanets has doubled approximately every 27 months.
Are there cases where students had discovered exoplanet(s)?
Indeed, there are cases where citizen scientists and school students had discovered an exoplanet or a quarter of them. A recent article on late January 2021, informs us of a four exoplanets discovery by two 16- and 18-year-old high school students in USA, that participated into a research mentorship program at the Center for Astrophysics; Harvard and Smithsonian. There is only one problem here, the paper published that describes the findings, is not accessible openly and freely to all, without a subscription to the Astronomical Journal; it is not published on an open access journal.
How OpenAIRE enabled and offered freedom to publish and share the process of a new exoplanet discovery by students in Athens, Greece
In Athens, Greece, in late 2019, a team of school students successfully identified an exoplanet! The discovery process is open and available on the Open Schools Journal of Open Science (OSJ), supported by OpenAIRE. As the students (authors) of the article state in their abstract, “Since 2009, Kepler Space Telescope has been recording small reductions (eclipses) in the light of distant stars due to the transit of planets in front of them. Our goal is to detect planets in orbit around distant stars from Kepler's mission data, following the Reading Method using two programs written by our team in programme language C. If the readings are detected and confirmed, we proceed to their analysis. characteristics of the planet: Ray, inclination, distance from the star, and especially if it is in the so-called "habitable zone" which will make it possible to maintain life. However, we have already identified such an exoplanet in orbit around the star KIC 1432789, the characteristics of which our team analyzed for the first time.” 
Download the new exoplanet discovery article from Open Schools Journal for Open Science
The Open Schools Journal for Open Science offered the opportunity to these brave young researchers to get exposed to the beauty of science and the magnificence of a scientific discovery. On behalf of OpenAIRE and OSJ, we wish them this discovery to keep inspiring them and to be only the beginning of their beautiful relationship with the field of research.
The article is available to all to download at the Open Schools Journal in Open Science Vol3 No1 (https://ejournals.epublishing.ekt.gr/index.php/openschoolsjournal/article/view/22398) or on Zenodo Open Schools Journal for Open Science community: https://zenodo.org/record/4549784#.YDEId2gzZnI
 The article is in Greek language and for the purposes of this article, the information is translated into English).