Supernova 1993J and its Fourier Transform

Supernova 1993J as seen with Very Long Baseline Interferometry. This image is made from observations using a world-wide array of 18 radio telescopes, including the NRAO Very Long Baseline Array, Very Large Array, Green Bank Telescope and antennas of the European VLBI Network and the NASA Deep Space Network. The whitish-yellow, glowing object is a radio-image of SN 1993J at a frequency of 8.4 GHz. The ring-shaped "mountains" on the ground represent the actual measurements made by the radio interferometer from which the radio-image was made. Mathematically speaking the radio-image is the Fourier transform of the measurements. Supernova 1993J exploded in 1993 in the galaxy M81, approximately 12 million light years away. The spherical shell of gas is expanding with a speed of about 5000 miles/sec. This spherical shell produces the ring-like structure seen in the radio image. The diameter is about one-half of a light year.

The VLBI Image was made by combining global Array observations made on three sessions between 1998 Dec. to 200 Nov. (PI N. Bartel; see Bietenholz, Bartel & Rupen, ApJ, 597, 2003 for details; see also Bartel et al, 2000, Science, 287, 112; Bietenholz, Bartel, & Rupen, 2001, ApJ, 557, 770; Bartel et al, 2002, 581, 404). The resolution is 0.7 milli-arcsecs. The "ground" shows the Fourier transform of the image, or the uv-plane.

Legacy Astronomical Images

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

Legacy Astronomical Image

SN 1993J

Michael Bietenholz, York University

N. Bartel, M. Bietenholz, M. Rupen

Very Long Baseline Array (VLBA)

EVN

DSN

2000-11-12

continuum

X

3.6 cm

8.4 GHz

RA 9:55:24.775, Dec: 69:1:13.704 (J2000)

0.000002 x 0.000002 degrees

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

Galactic Sources Series

Supernovae Unit