3m Radio Telescope

Located on the roof of the physics building is a an MIT Haystack Small Radio Telescope, with a dish diameter of 3m. The telescope can investigate a variety of radio sources such as distant pulsars, our own Sun and perform measurements of the rotation of the Milky Way galaxy.

The neutral hydrogen spectral line is created by the change in energy state of neutral hydrogen atoms and is always at the precise frequency 1420.4 Mhz with a wavelength of 21cm.This frequency is of great interest to astronomers as it can penetrate through clouds and interstellar clouds of dust and gas, revealing objects that would normally be hidden in optical wavelengths.

Investigation of this spectral line can tell us more about the abundance of hydrogen in our universe, and by observing the radial velocity of hydrogen gas in galaxies we can study their dynamics.