Research

Supermassive black hole (SMBH) growth predominantly occurs in the absence of major mergers, but the causes are unknown. In AGN (active galactic nuclei), the SMBH is undergoing a rapid period of growth and accretion, so by studying AGN, we can study SMBH growth.

My work

I investigate bar-driven AGN growth. Recently I have used large optical surveys such as DESI Legacy Surveys to determine the AGN fraction in unbarred, weakly barred and strongly barred galaxies, as well as the star-forming (SFing) fraction.

Highlights

The AGN fraction is higher in strongly barred galaxies than weakly barred, where it is in turn higher than the AGN fraction in unbarred galaxies. This strongly indicates that bars and AGN are linked, and bars are somehow involved in the switch-on of AGN

Another citizen science project I am tangentially involved with is the Planetary Response Network, which aids with disaster relief around the world

What we do

In the same way that volunteers can speed up galaxy classification, we can also ask them to identify regions with high areas of damage from satellite imagery in the wake of natural disasters. Working with aid organisations, we can find out what data and coverage is most urgently needed. We show volunteers before and after pictures, and use the data to create heat maps which are forwarded to the aid organisations

Hurricane Melissa

The most recent emergency deployment was in November 2025, in the wake of Melissa which hit the Caribbean. Thanks to our 2,500 volunteers, we were able to create heat maps of damage for Jamaica and Haiti's roads, ports and airports within 4 days of the site going live, and we could pass this information of to the Logistics Cluster at the World Food Programme

Sudan Project

I only get involved with the emergency response projects, however the current project is on mapping dry riverbeds in Sudan, in order to predict flooding, and you can get involved here.