The 21 m is considered to be a medium-aperture telescope where apertures of radio telescopes have been generally categorized by a ratio of the aperture diameter to the incident wavelength. At L-Band, the ratio of the aperture diameter of the Antenna to the incident wavelength exceeds 100 while at higher frequencies this ratio becomes 1000 or higher. Medium-aperture telescopes such as the Antenna have many advantages as active laboratories and as research instruments for both students and faculty members. Medium-aperture centimeter-wave instruments like the Antenna can produce significant scientific contributions: for example, while time on large-aperture instruments is generally heavily subscribed for phenomenon-specific observations, medium- aperture telescopes can devote time to long-term monitoring campaigns, sky surveys, and event-specific phenomena such as supernovae, gamma-ray bursts and apparitions of comets. In this respect, the Antenna stands to produce a lasting legacy of crucial datasets at multiple frequencies to the entire astronomical community. Radio astronomy research projects include:

•  long-term monitoring campaigns (AGNs)
•  sky surveys (Dynamic Mapping of HI in the Milky Way)
•  transient phenomena (supernovae and GRBs)

Maps of the spatial distribution of RF emission associated with astronomical objects are produced by raster scanning across the field of view and producing a map of the RF intensity distribution field by integrating the entire post-detection frequency band of 6 MHz into a single, integrated channel map (0th moment map). An image of the velocity field (1st moment map) and an image of the velocity dispersion (2nd moment map) can also be produced. Analysis of these maps of the phenomena in “velocity space” allows astronomers to calculate the kinematics of the system and thereby derive the dynamics, then infer the energetics, and virial masses, along with other insights into the underlying physics of these systems. An example of a 0th moment map showing the spatial distribution of radio emission from a supernova remnant (3C 157) is shown (left center). The detail seen in this image demonstrates the sensitivity and resolution of the 21 m.

For More Information and Specifications Please View:

"The 21M Antenna Overview" (PDF)

"A University-Based Ground Station: The 21 m Antenna at
Morehead State University" (PDF)