Researchers have detected an unusually large, previously undetected molecule in the Cat's Paw Nebula, a star-forming region about 5,500 light-years from Earth. At 13 atoms, the compound, called 2-methoxyethanol, is one of the largest molecules ever identified outside our solar system, the scientists reported April 12 in The Astrophysical Journal Letters.
"When we observe interstellar sources with radio telescopes, we can collect the rotational signal from the gaseous molecules in these regions of space," first study author Zachary Fried, an astrochemist at MIT, told Live Science in an email"Because the molecules in space obey the same quantum mechanical laws as those on Earth, the rotational transitions observed in the telescope data should line up with those measured in the lab.
"These molecules are typically much less abundant than smaller hydrocarbons that have simpler formation routes," Fried said."Additionally, the spectral signals of these molecules are distributed over a greater number of transitions, thus making the individual spectral peaks weaker and more difficult to observe."
Methoxy-containing species had previously been detected in a part of the Cat's Paw Nebula, also called NGC 63341, and in IRAS 16293, a binary system in the Rho Ophiuchi cloud complex, located 457 light-years from Earth. As such, the team had a good idea of where to look for the new molecule.