We spend so much time talking about the Arecibo radio telescope with regard to planetary radar that it’s nice to come back to its applications in deep space. Thus the news that astronomers using the instrument have found key ingredients of amino acids in a galaxy 250 million light years from Earth in the constellation Serpens. The molecules are methanimine and hydrogen cyanide which, with the addition of water, form the amino acid glycine, considered a key ingredient in life on Earth.
Arp 220 is known for a high rate of new star formation, and recent Hubble work has discovered more than 200 star clusters at its heart. Observing it at a range of frequencies and using the wide-band mode of the main spectrometer, the team, led by Arecibo astronomer Christopher Salter, found the characteristic emission of the molecules clearly evident. Says Emmanuel Momjian (NRAO), “The fact that we can observe these substances at such a vast distance means that there are huge amounts of them in Arp 220. It is indeed very intriguing to find that the ingredients of life appear in large quantities where new stars and planets are born.” This Cornell news release has more.
Image: The galaxy Arp 220, where the recent finds were made. The Hubble Space Telescope’s Advanced Camera for Surveys has uncovered more than 200 mammoth star clusters in its heart. The clusters are the bluish-white dots scattered throughout the image. The heftiest Arp 220 cluster — about 10 million solar masses — is twice as massive as any comparable star cluster in the Milky Way. Arp 220 collided with another galaxy about 700 million years ago, fueling the frenzy of star birth in a small region about 5,000 light-years across. The galaxy is a nearby example of the aftermath of two colliding galaxies. Credit: Credit: NASA, ESA, and C. Wilson (McMaster University, Hamilton, Ontario, Canada).
Bear in mind that Arecibo has recently been ugraded with new receivers, thus allowing the 800-MHz wide-band study the team performed on Arp 220. The galaxy itself has been the subject of intense scrutiny. Classed as an ultra-luminous infrared galaxy (ULIRG), it seems to have an active galactic nucleus (AGN) at its core. The high level of new star formation is thought to be related to a collision between two galaxies, making Arp 220 the brightest of the three galactic mergers closest to Earth. The star formation itself is occurring in a region about 5000 light years across, where gas and dust are dense enough to equal all gas and dust in the Milky Way. More on the latter finding in this Hubble news release.