CCERA 21cm Sky Map - Marcus Leech (2020 March)


There are a plethora of observing regimes and projects that are routinely used in radio astronomy, but the production of a sky map is a project that is easily accessible to the amateur observer, and produces satisfying results.

Such a map shows the brightness distribution over the sky for a given set of observing wavelengths. In the case of the 21cm hydrogen line wavelength, maps show the distribution of hydrogen over the sky. For amateur observers, such maps generally show the distribution within our own galaxy, since extra-galactic hydrogen is considerably more faint, and significantly red/blue shifted relative to the rest frequency of 1420.40575MHz, due to relative motion between the observer and the target extra-galactic hydrogen.