M51 from the NOAO 0.9m at KPNO

Place mouse in the image to see outline of the HST field. Click on the image for a larger view. Credit: Travis Rector & Monica Ramirez (NOAO)

Visit a Related Site of M51 at the NOAO Website

This image of M51 was taken with the NOAO Mosaic CCD camera on the National Science Foundation's 0.9-meter telescope located at Kitt Peak National Observatory near Tucson, AZ. Located in the constellation of Canes Venatici, the "hunting dogs", M51 consists of the large spiral galaxy NGC 5194 and its smaller companion NGC 5195. Hot, massive stars which recently formed in NGC 5194 give the galaxy its bluish color. The reddish areas are nebulae in the galaxy in which stars are rapidly forming. M51 is approximately 31 million light years away and over 65,000 light years in diameter. The color image was generated by combining images taken through five filters (B, V, R, I and Ha). The full image (available by clicking on the image at left) is only one tenth of the entire field of view of Mosaic on the 0.9-meter telescope.

Near-infrared and Optical Observations
of the Heart of M51

Center of M51 in the Near-Infrared NICMOS FILTERS: Continuum-subtracted Paschen a + F222M; F160W (K); F1110W (J).	Center of M51 in the Optical WFPC2 FILTERS: Continuum-subtracted Ha + F814W (I); F555W (V); F439W (B).

The Infrared Heart of The Whirlpool Galaxy

The research team, led by Nick Scoville of CalTech, is also studying The Whirlpool Galaxy at near-infrared wavelengths with the NICMOS instrument on the Hubble Space Telescope. Two distinctly different looking images of the center of M51 are displayed above, at the same size and scale. This image pair contrasts light that the Hubble Telescope is able to detect in near-infrared wavelengths (taken with the NICMOS camera) with light from optical wavelengths (taken with the WFPC2 camera). At near-infrared wavelengths, the dusty clouds are more transparent and the true distribution of stars is more easily seen than in optical images. In addition, regions of star formation that are obscured in the optical images are newly revealed in the near-infrared images.

Activity at the center of the galaxy in both wavelengths indicates the possible presence of a nuclear black hole. A close-up view of the the central optical image appears at left. This image was taken with the Planetary Camera chip of the WFPC2 camera and has a scale of 2 kpc across (1/16 the size of the above image field). The resolution of this close-up image allows the science team to peer right into the core of the nucleus and understand what is going on at the very center of this galaxy.

Image Credits: N. Scoville, M. Polletta, S. Ewald, S. Stolovy, R. Thompson, M. Rieke

Animation of M51: Including Ground- and Space-based Data!

Animation Image Credits

Ground-based image
Travis Rector & Monica Ramirez (NOAO)

HST Image
Credit: NASA and The Hubble Heritage Team (STScI/AURA). Acknowledgment: N. Scoville,M. Polletta,S. Ewald,S. Stolovy, R. Thompson, M. Rieke and T. Rector.

Link to the 1994 STScI release of a Supernova in M51.