Neutral Hydrogen & Infrared Probes of Star Fomation


Image of Hickson Compact Group 7 depicting neutral hydrogen gas (red) from the VLA and infrared observations from the IRAC instrument on the Spitzer Space Telescope (blue and green). Neutral hydrogen gas tells astronomers about the distribution of the gas (shown here in red) and the dynamics of the group. The infrared observations show stellar light (blue) and warm emission from dust (green)- the signature of stellar formation. Studies of neutral hydrogen and infrared emission in compact groups help astronomers to better understand their evolution and how the dynamical state is linked to the level of star formation activity.
This image of HCG 7 is composed of VLA HI C+D array configuration data. The Spitzer IRAC bands shown are (3.6, 4.5) microns in blue and (5.8, 8.0) microns in green.


Legacy Astronomical Images


NRAO/AUI/NSF does not hold full copyright for this image. Contact the archivist for details.


Legacy Astronomical Image

Object Name

HCG 007

Photo Credit

Amanda Heiderman; NRAO Summer Student/UC Berkeley


Amanda Heiderman, John Hibbard, Kelsey Johnson


Very Large Array (VLA)

Observation Date


Type of Observation

spectral line

Center of Image

RA 0:39:23.000, Dec: 0:52:41.000 (J2000)

Field of View

0.166667 x 0.166667 degrees


Contact the archivist for a high resolution tif of this image.


Galaxies Series


Clusters Unit


Legacy Astronomical Images, “Neutral Hydrogen & Infrared Probes of Star Fomation,” NRAO Archives, accessed December 3, 2021,