The left picture shows the galaxy M51 as seen with the Hubble Space Telescope optical light. On the right, an SMA observation of the same galaxy, translated into so-called 'false colors' to represent different intensities. While the galactic spiral structure is clearly visible in both pictures, the SMA observations reveal gas, dust and regions of active star formation at exactly the positions of the dark regions in the optical image. By revealing such complementary information and examining the features of the gas and dust that are not visible in optical light, the SMA will further our understanding of the galaxy M51 and many other interesting astronomical objects.
(optical picture credits: N. Scoville, T Rector et al., Hubble Heritage Team, NASA)
S. Matsushita, K. Sakamoto, C.-Y. Kuo, P.-Y. Hsieh, D.-V. Trung, R.-Q. Mao, D. Iono, A. B. Peck, M. C. Wiedner, S.-Y. Liu, N. Ohashi, and J. Lim,
Submillimeter Array 12CO (J=3-2) Interferometric Observations of the Central Region of M51,
2004, ApJ, 616, L55