Zoom into the central light-year of the Galaxy. Images show CO (J = 3–2) high-speed channel maps (left: v_LSR = −250 to −200 km s⁻¹, middle: v_LSR = +150 to +200 km s⁻¹, and right: v_LSR = +200 to +250 km s⁻¹), showing the integrated line intensity from 0 to 130 K km s⁻¹, and revealing molecular gas close to Sgr A^*. Green contours show the ionized gas emission (Irons et al. 2012). The yellow and magenta tracks are segments of the Keplerian elliptical orbits along the eastern and northern arms respectively (Zhao et al. 2009).