NRAO: National Radio Astronomy Observatory

About this Image

This is a pseudo-color representation of Sgr A and its halo at 90 cm (332 MHz). The coding of the brightness scale is indicated by the color bar. Sgr A East is a non-thermal shell source that could be a supernova remnant or a very low-luminosity example of a radio component associated with the active nucleus of a spiral galaxy. The most dramatic aspect of the new 332 MHz observations is the appearance of the Sgr A West spiral features in absorption against Sgr A East. Based on these results, Sgr A East is situated behind Sgr A West, the center of the galaxy. The halo is in front of or surrounds the former sources. The HII regions to the east of Sgr A East are probably associated with the 50 km/s molecular cloud. The 7 arcmin halo (20 pc) has a non-thermal spectrum with turn-over below 1 GHz.

Investigator(s):  W. M. Goss, K. R. Anantharamaiah, R. D. Ekers, and A. Pedlar

Alternate Resolutions

Help

This image is available in the following downloadable versions:

• 480 x 520 color JPEG
• 900 x 975 color JPEG
• 1939 x 2100 color TIFF

If you would like to obtain a higher resolution version of this image, please contact Pat Smiley.

For More Information

• Read the Journal article
• Up one level for more info on Galactic_Center
• For unfamiliar terms, visit the NRAO Radio Astronomy Glossary

Technical Data

Telescope	VLA
Date of Observation	1987-00-00
Type of Observation	Continuum Observations
Band	P
Wavelength	90 cm
Frequency	330 MHz
Center of Image	RA: 17:43:15.00, Dec: -28:52:0.00 (J2000)
Field of View	0.2167 x 0.2167 degrees
Technical Caption	VLA in A,B,C,D configuration using 15 antennas. Angular resolution is 12" x 12".



Astronomical database entries for Sgr A
• Query SIMBAD for more Sgr A data

---

SEARCH THE IMAGE GALLERY To search the Image Gallery for other images of Sgr A, click the Submit button. Object Name Show Results As: Thumbnails List To search the Image Gallery for similar images, click the Submit button. Category Sub-Category Telescope Mode Show Results As: Any Galaxy AGN Galactic_Sources Solar_System Miscellaneous Telescopes Historical Any Black Holes Galactic Center Galactic Halo Planetary Nebula Pulsars/Neutron Stars Supernova Supernova Remnants Stars Star Forming Regions Any GBT VLA VLBA ALMA 12 m 140 ft Any Continuum Spectral Line Thumbnails List For more search options, please use our Advanced Search form.