TUNA Lunch Talk:

Arielle Moullet


Looking at the Kuiper Belt from the thermal side

June 12

12:10PM, Room 230, NRAO, Edgemont Road


IR, (sub)mm and cm-wavelength observations have been so far obtained on about 50 Kuiper Belt objects and Centaurs, measuring the thermal emission from the surfaces of these distant objects that are believed to be amongst the most pristine in the Solar System. These observations can be used to apply the radiometric method, that is the most effective way to derive the equivalent size of these objects that are usually to small to be resolved. The comparison of thermal and optical rotational lightcurves allows one to distinguish shape effects from albedo distribution to explain brightness variations. Thermal measurements are also indicative of surface properties such as roughness, albedo and thermal inertia. The physical description of Centaurs and Kuiper Belt objects is essential to characterize the processes acting on their surfaces, as well as to retrace the formation and evolution of the different populations, in particular by identifying families and correlations between orbital and physical properties. Thanks to their unprecedented sensitivity, the most recent thermal instruments (Herschel, ALMA and the JVLA) are and will be playing a fundamental role in the understanding of the Kuiper Belt. In this talk, I will describe different projects that can be performed with ALMA - Cycle 1 and full science - based on specific examples. At completion, ALMA should be able to provide thermal measurements for bodies as small as 100 km in diameter (more than 30% of the known population). In addition to lightcurve and radiometric measurements, ALMA's exquisite spatial resolution could be used to provide the first thermal imaging of the largest objects, directly determine sizes and shapes, as well as to separate the members of several multiple systems. Finally, CO-line observations could be performed to detect and/or characterize the thin KBOs' atmospheres.