A twisted ring of gas stretching more than 600 light-years across the heart of the Milky Way galaxy has been observed in its entirety for the first time. The gaseous ring, which gives birth to new stars, has a kink in the middle, giving it the look of a cosmic infinity symbol.
Parts of the ring have been seen before, but the European Space Agency's Herschel Space Telescope has just made unprecedented observations of the whole structure. The Herschel spacecraft is specially suited to peer into the Milky Way's center because it detects infrared and sub-millimeter light, which can penetrate through the dust hovering between here and there.
According to a statement from the Jet Propulsion Laboratory in Pasadena, Calif., astronomers were shocked by what they saw when they aimed the telescope at the galaxy's inner ring: "[The] ring, which is in the plane of our galaxy, looked more like an infinity symbol with two lobes pointing to the side," the laboratory said. "In fact, they later determined the ring was torqued in the middle, so it only appears to have two lobes. To picture the structure, imagine holding a stiff, elliptical band and twisting the ends in opposite directions, so that one side comes up a bit." [Top 3 Questions People Ask Astrophysicists (and Answers )]
Scientists don't yet understand why the newly observed infinity symbol is twisted and kinked, and little is known about how gas rings, and even rings within larger rings, form in spiral galaxies in the first place. And there's yet another mystery: The torqued portion of the new ring appears to be slightly offset from the center of the galaxy, wherein lies a massive black hole .
"This is what is so exciting about launching a new space telescope like Herschel," said Sergio Molinari of the Institute of Space Physics in Rome, lead author of a new paper on the ring in the journal Astrophysical Journal Letters. "We have a new and exciting mystery on our hands, right at the center of our own galaxy."
What If Our Solar System Had Formed Closer to the Milky Way's Edge?