PDS logoPlanetary Data System
PDS Information
Find a Node - Use these links to navigate to any of the 8 publicly accessible PDS Nodes.

This bar indicates that you are within the PDS enterprise which includes 6 science discipline nodes and 2 support nodes which are overseen by the Project Management Office at NASA's Goddard Space Flight Center (GSFC). Each node is led by an expert in the subject discipline, supported by an advisory group of other practitioners of that discipline, and subject to selection and approval under a regular NASA Research Announcement.
Click here to return to the Photojournal Home Page Click here to view a list of Photojournal Image Galleries Photojournal_inner_header
Latest Images  |  Spacecraft & Technology  |  Animations  |  Space Images App  |  Feedback  |  Photojournal Search  

PIA03605: Dwarf Galaxies Swimming in Tidal Tails
 Mission:  Spitzer Space Telescope
 Instrument:  IRAC
 Product Size:  848 x 711 pixels (w x h)
 Produced By:  California Institute of Technology 
 Full-Res TIFF:  PIA03605.tif (1.811 MB)
 Full-Res JPEG:  PIA03605.jpg (60.3 kB)

Click on the image above to download a moderately sized image in JPEG format (possibly reduced in size from original)

Original Caption Released with Image:

This false-color infrared image from NASA's Spitzer Space Telescope shows little "dwarf galaxies" forming in the "tails" of two larger galaxies that are colliding together. The big galaxies are at the center of the picture, while the dwarfs can be seen as red dots in the red streamers, or tidal tails. The two blue dots above the big galaxies are stars in the foreground.

Galaxy mergers are common occurrences in the universe; for example, our own Milky Way galaxy will eventually smash into the nearby Andromeda galaxy. When two galaxies meet, they tend to rip each other apart, leaving a trail, called a tidal tail, of gas and dust in their wake. It is out of this galactic debris that new dwarf galaxies are born.

The new Spitzer picture demonstrates that these particular dwarfs are actively forming stars. The red color indicates the presence of dust produced in star-forming regions, including organic molecules called polycyclic aromatic hydrocarbons. These carbon-containing molecules are also found on Earth, in car exhaust and on burnt toast, among other places. Here, the molecules are being heated up by the young stars, and, as a result, shine in infrared light.

This image was taken by the infrared array camera on Spitzer. It is a 4-color composite of infrared light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red). Starlight has been subtracted from the orange and red channels in order to enhance the dust features.

Image Credit:
NASA/JPL-Caltech/Cornell Univ.

Image Addition Date:
2005-12-01