Rare element found in exoplanet’s atmosphere

Newswise —

The planet KELT-9 b holds the record for being the hottest exoplanet in the galaxy, located approximately 670 light years away from Earth and orbiting a distant star. With an astounding average temperature of 4,000 degrees Celsius, this celestial entity has captured the attention of astronomers worldwide since its initial discovery in 2016. Recently, a study published in Astronomy & Astrophysics has uncovered novel insights regarding the peculiar and searingly hot planet’s atmosphere.

Nicholas Borsato, a PhD student in astrophysics at Lund University, explains that they have devised a fresh approach that enables them to gather more comprehensive data. Through this innovative technique, they have identified seven elements, among them the uncommon element terbium, which has never been detected in the atmosphere of any other exoplanet.

Terbium is categorized as a rare earth metal and is classified as one of the lanthanoids. The element was first discovered by Swedish chemist Carl Gustaf Mosander in 1843, at the Ytterby mine situated in the Stockholm archipelago. Terbium is exceedingly scarce in the natural environment, and currently, approximately 99 percent of the world’s terbium production occurs in the Bayan Obo mining district located in Inner Mongolia.

“Finding terbium in an exoplanet’s atmosphere is very surprising”, says Nicholas Borsato.

The majority of exoplanets are typically detected through measurements of their host stars’ luminosity. During an exoplanet’s transit, its passage in front of the host star leads to a reduction in the star’s brightness. With their sophisticated measurement technique, the scientists have successfully eliminated the primary signals from KELT-9 b’s atmosphere. This breakthrough allows for the potential discovery of additional information regarding other exoplanets’ atmospheres.

Nicholas Borsato elucidates that gaining further knowledge about the denser elements can aid in ascertaining crucial information such as the exoplanet’s age and the manner in which it was created.

Exoplanets, also known as extrasolar planets, refer to planets that exist in solar systems other than our own. The first confirmed detection of an exoplanet was made in 1992, which was orbiting a neutron star. Subsequently, in 1995, the first exoplanet revolving around a sun-like star was discovered. To date, scientists have documented over 5,000 exoplanets. The presence of exoplanets often raises inquiries about the likelihood of extraterrestrial life in the universe.

The identification of dense elements within the atmospheres of ultra-hot exoplanets marks another milestone in comprehending the mechanics of planetary atmospheres. As we continue to deepen our understanding of these celestial bodies, we enhance our likelihood of discovering a “second Earth” in the future. This optimistic sentiment is conveyed by Nicholas Borsato to conclude his remarks.