Professor de Mello’s scientific research is in the field of extragalactic astronomy.
She studies how galaxies transform and evolve to become galaxies like the Milky Way.
Her contributions to the field goes from discovering a supernova (SN1997D), to modelling the stellar population of starburst galaxies (Starburst99), to discovering blue blobs outside colliding galaxies, to taking deep images with the Hubble Space Telescope.
Interacting galaxies are excellent laboratories to study environmental effects in galaxy evolution. During my PhD I studied pairs of galaxies made of one elliptical and one spiral galaxy and discovered that many of those ellipticals show young stellar populations which is not common in isolated ellipticals. I attributed that to the presence of the spiral companion and to the possible gas transfer from the spiral to the elliptical.
In 2008 I started discovering blue blobs outside colliding galaxies using the Ultraviolet Satellite GALEX. In my first discovery I noticed that those blobs were within the hydrogen clouds that had been left outside galaxies (M81 and M82) during their collision. I used the Hubble Space Telescope to understand that those blobs were very young stellar associations. Together with a team of students we discovered many more blobs in many more interacting galaxies. We now know that those stellar nurseries were formed from gas that was reprocessed inside the galaxies.
In 1997 I joined the Hubble Deep Field South team at Space Telescope Science Institute. The HDF-S was the second deep field taken with Hubble revealing thousands of galaxies in apparently empty areas of the sky. In 2002 I joined the GOODS (Great Observatories Origins Deep Survey) team that took many deep fields and originated the Ultra Deep Field. I am also part of the CANDELS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey) team and the UV-UDF.