LMC68 nova explosion 100 times brighter than sun

Astronomers have made a surprising discovery about a nova called LMC68, located in the Large Magellanic Cloud, using near-infrared light. This study is the first of its kind for a recurrent nova beyond our Milky Way galaxy. They found high temperatures and unusual chemical signatures, indicating a very powerful explosion. Nova explosions happen in binary star systems where a white dwarf star siphons material from a cooler companion star. The material accumulates and eventually explodes in a thermonuclear event. While most novas explode only once, recurrent novas like LMC68 can erupt many times, typically every few years. LMC68 was first observed in 1968 and has erupted multiple times since, making it the first extragalactic recurrent nova found. After its latest explosion in August 2024, researchers used large telescopes to study its light to learn more about its conditions and chemical makeup. The astronomers used a method called spectroscopy to analyze LMC68’s light. They expected typical signatures of various heavy elements, but instead found a bright signal from ionized silicon, which was surprisingly intense. This ionized silicon was nearly 100 times brighter than our sun. The absence of other expected elements raised questions. Researchers believe that the surrounding environment of the nova may affect the explosion and its visible signatures. LMC68's companion star likely has fewer heavier elements, a situation more common in the Large Magellanic Cloud. The high temperature of 5.4 million degrees Fahrenheit in LMC68 might explain the unique observations. High energy and low metallicity could lead to more powerful explosions and affect how elements behave during the event. The team suggests more studies are needed to understand these phenomena better. Their research highlights the importance of using advanced telescopes to study novas in different environments and improve our knowledge of these cosmic events. The findings were published in a scientific journal.