Simon Ellingsen is an Executive Director of the International Centre for Radio Astronomy Research (ICRAR) and is based at the University of Western Australia node Ellingsen attended University of Tasmania, located in Hobart, Tasmania, where he received a Bachelor's degree (First-class honours) in 1991.

Notable contributions include the first unbiased search for 6.7 GHz methanol masers, which identified a large number of previously unknown regions of high-mass star formation,[2] discovery of a number of new interstellar methanol maser transitions[3] and the demonstration that class II methanol masers trace a very early phase of high-mass star formation.

In 1998 Ellingsen and Gray conducted searches using the 26-meter dish at the Mount Pleasant Radio Observatory in Hobart, Tasmania.

Ellingsen has been involved in running research facilities and associated projects at The University of Tasmania for many years, most recently a Space Infrastructure Fund grant[8] to construct a new satellite tracking antenna at the Greenhill Observatory.

In April 2024 he commenced as the Executive Director for the International Centre for Radio Astronomy Research (ICRAR) and is based at the University of Western Australia node.