Over the summer of 2020 the School of Mathematics and Physics at the University of Lincoln took delivery of its first radio telescope. The aim is to have it installed and ready to use for the 2020/2021 academic year. This allows the School to continue to provide real experiments that can be conducted remotely for our physics students.
The radio telescope is a Spider 300A and has a 3m aperture which is designed to make observations around a frequency of 1420 MHz, the 21cm emission line of neutral hydrogen.
Benefits of Radio Astronomy
Two of the key benefits of having a radio telescope is the ability to make measurements remotely and that observations can be made during the day, even if it is cloudy. The longer wavelength of radio waves means that they are not as affected by clouds, atmospheric turbulence and the Sun as waves in the visible part of the spectrum are. This means radio telescopes generally operate at their diffraction limit.
What Can We observe With a Radio Telescope?
By observing the 21cm neutral hydrogen line we are able to:
- Observe the hydrogen content in the sky and of nearby galaxies.
- Variability of radio loud objects, like quasars which are distant galaxies with active supermassive black holes.
- Changes in the Solar output in the radio part of the spectrum that relates to sunspots and Solar activity.
- Rotation curve of the Milkyway by using the Doppler shift in the 21cm emission line. Rotation curves of galaxies was one hints at the existence of dark matter due to their unexpected high rotation velocities.
Above: A map of the 21cm emission in the sky. The brightest horizontal band that can be seen is due to hydrogen in our own milky.