Interesting talk today in the DTM Astronomy Seminar from Dr. Anne Verbiscer of UVA Astronomy.
She spoke about the Kuiper Belt binary object Sila-Nunam, two enigmatic bodies orbiting 40 times farther from the Sun than the Earth. They have radii of about 100 km, comparable to some of Saturn’s small moons, and they orbit one another every 12 days, as they both go around the Sun together every 300 years.
In recent and coming years, Sila and Nunam will occult one another several times, allowing astronomers to measure their radii, which aren’t very well known, and learn about their densities, internal structures, and orbit.
Dr. Verbiscer presented several very interesting infrared spectra and observations in visible wavelengths, showing the small dips in light from the system, as one object blocked out the other object. These observations are very challenging because objects are so small and far away, but analysis of these data are ongoing and will tell us about these strange, distant, and cold objects.