Research Projects

This page lists presently-offered PhD or MSc level research projects. These are representative of many other topics in astrophysics, imaging and instrumentation that are ongoing and encompassed by our group. Come talk to us if you are interested!

Research Projects

Planetismals forming in a simulated disk

Imaging Newborn Exoplanets
The ability to image the process of creation of a newborn planet, and to separate the faint mote of planetary light from the powerful glare of its host star is among the most sought-after capabilities in all of contemporary astronomy. Indeed, this is among the signature quests of all modern science, for it provides answers to some of the most profound questions about the origins of our own planet and the potential for life on other worlds. Our group are world leaders in pioneering new technologies for this technically demanding field, recently delivering the first resolved images of exoplanets at birth. New research projects in these areas exploit our unsurpassed array of innovative instruments, including interferometric imaging experiments at the world's largest telescopes including the Large Binocular Telescope, Gemini, Keck and VLT. All these projects were originated, designed and led from Sydney. Active areas of astronomical research that can be addressed by these unique devices include the formation of stars and the assembly of exoplanetary systems within the circumstellar disks, brown dwarf formation and evolution, and remnant dusty debris disks.

The JWST space telescope

Interferometry with the JWST space telescope
The James Webb Space Telescope stands to inherit the mantle of the Hubble Space Telescope as the pre-eminent astronomical observatory of the 21st century. With a primary mirror more than 6 meters in diameter, this mission will fly to the L2 Lagrangian point to begin a unique mission of discovery. When it does so, it will deploy a unique interferometric imaging mode designed, built and led from the University of Sydney. This aperture masking interferometer is aboard the NIRISS instrument, and will empower the JWST to make the finest and most sensitive surveys for the presence of faint structures in the environment of forming stars that have ever been achieved. This opens an entirely new window on the origins of structure from stars to brown dwarfs to planets, informing our own origins and place in the universe as well as expectations for the ubiquity and diversity of exoplanets in the Galaxy.

circumstellar disk of MWC758

Peering into the cradle with VAMPIRES
Our new VAMPIRES instrument has just been commissioned at the 8-meter Subaru telescope in Hawaii. VAMPIRES is a Visible Aperture Masking Polarimetric Interferometer for Resolving Exoplanetary Signatures - says it all really! With this brand-new and world-leading instrument, this project will deliver the first resolved images of the circumstellar disks that form the cradle of planetary birth. A key innovation is that VAMPIRES will do this in polarised light, so that subtle and difficult to read signatures such as spiral density waves, and scattering phenomena associated with the exact nature of the dust present in the protoplanetary disk will be revealed for the first time. VAMPIRES can image the region (marked in red) inaccessible to present technologies but believed to be the most promising for hosting young forming planets.

Surface imaging of rapid rotator star Altair

The stellar surface imaging project
The twin PAVO instruments (PAVO is the Southern constellation of the Peacock) were built by our group at the SUSI (NSW) and CHARA (California) arrays. These instruments now set the standard for sensitivity and resolution in optical interferometric imaging, for the first time enabling us to answer a question which countless generations must have dreamed about: ``What would it look like if I could zoom up to see a distant star at close quarters?''. The sunspots and prominences exhibited by our own sun may be quite tame in comparison with the fireworks displayed by many of the exotic stars in our galaxy. The surfaces of several classes of strongly magnetic star should show strong surface mottling, with spectacular patterns of light and dark regions criss-crossing the stellar disk. Still other stars are distorted from the normal circular disk by rotation rates approaching break-up, or by tidal effects from an extremely close binary companion star stretching the surface into an egg shape. New observations, for the first time enabled by the PAVO instruments, will open a unique new window into the exotic physics which governs such extreme astrophysical environments. In this project, you will learn about design of leading edge astronomical instrumentation, construct your own observing program and conduct observations at both the SUSI array in Narrabri and the CHARA array in California.

The Red Square nebula

The Riddle of the Red Square
The "Red Square" is a spectacular, newly-discovered bipolar nebula (Tuthill et al, Science 2007). Using cutting-edge imaging techniques such as Adaptive Optics and Optical Interferometry implemented at some of the worlds largest observatories (e.g. Keck, Gemini), we have revealed beautiful and startlingly detailed structures. A striking set of rungs crossing the nebula imply the existence of a highly regular series of nested bicones: possibly a relic of previous episodes of eruption or instability in the host star MWC 922 at the heart of the system. What is particularly compelling about this object is the correspondence between the sharp rung structures we see in The Red Square, and the beautiful polar rings now exhibited by the only naked-eye supernova since the invention of the telescope: SN 1987A. The origin of these mysterious rings stands out as one of the foremost unsolved problems in Supernova astronomy, and in the Red Square, we may have found the best example of a candidate progenitor for these structures. For this project, you will unravel the physics of this fascinating target and participate in new observing programs for the Keck telescopes (Hawaii) and VLT telescopes (Chile). In revealing the true nature of the enigmatic star MWC 922, we hope to solidify the links between this new nebula and the relic structures around SN 1987A. More information on the Red Square is on this page.

The SUSI interferometer

Galactic Paleontology with Metal Poor Stars
Ultra metal-poor stars are the living fossils of the stellar kingdom. Although elements heavier than Helium only make up a tiny fraction of any star, they have a profound effect on the stellar structure. Consequently stars born when the universe was substantially younger, before heavy elements were formed, should stand out from the crowd exhibiting dramatically different physical and thermal structure -- or so the theoretical models tell us. Because these fossil stars are rare and far from Earth, nobody has ever been able to examine one in detail. Until now. Your job in this project will put these stars under the microscope using the most powerful imaging arrays ever built: The Sydney University Stellar Interferometer and the CHARA array in Southern California. In making the first accurate measurements of the basic properties of metal-poor stars, you will determine whether these exotic objects are indeed as weird as theorists predict. The project then takes direct aim at one of the key questions in cosmology: the lithium abundance of very old stars is significantly lower than Big-Bang nucleosynthesis predicts. Where is the missing Lithium hiding, or is this a chink in the armor for Big-Bang cosmology?