A team of Japanese researchers has observed for the first time an extragalactic hot molecular core (HMC), a large cloud full of complex chemicals around a newborn star.
The core is located around a massive star called ST11 in the Large Magellanic Cloud, which is a satellite galaxy of the Milky Way, about 160,000 light-years from us. Although similar in structure to the HMCs found in the Milky Way, this one has a very different chemical composition, suggesting that the universe’s chemistry could be a lot more varied than we thought.
In a paper, published in the Astrophysical Journal, the researchers studying the HMC found that it has a mass 115 times that of our Sun.
The most prominent molecules in the HMC around ST11 are sulfur dioxide, nitric oxide, and formaldehyde. It was, however, found to be lacking in organic compounds like methanol, which are usually abundant in HMCs in the Milky Way.
“The observations suggest that the molecular compositions of materials that form stars and planets are much more diverse than we expected,” said lead author Takashi Shimonishi, from Tohoku University in Japan, in a statement.
The Large Magellanic Cloud has a lower abundance of elements heavier than helium compared to the Milky Way, so that could explain the different chemical composition seen around ST11, which is estimated to be 50 solar masses.
These observations were possible thanks to the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, which has now demonstrated itself to be sensitive enough to detect a huge array of different molecules even in a compact region such as this.
"This is the first detection of an extragalactic hot molecular core, and it demonstrates the great capability of new generation telescopes to study astrochemical phenomena beyond the Milky Way," added Shimonishi.
The chemicals found around young stars are believed to play a crucial role in the formation and composition of planets, and in the case of Earth, in the formation of life. Such a dramatic change in chemical composition across the universe might mean there are different ways for planets and even life to form.
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