We propose to make an albedo and radius survey of 100 cometary nuclei using IRS PU and MIPS imaging. We focus on Jupiter family comets (JFCs), which have dynamical and evolutionary connections to other Solar System groups: transneptunian objects (TNOs), Centaurs, Trojan asteroids, and extinct comet candidates. However, among these groups, the

Aims.A new theoretical calibration of surface-brightness fluctuations (SBF) for single age, single metallicity stellar populations is presented for the optical and near-IR broad-band filters, as well as for the HST WFPC2 and ACS filters. Methods: .The IAC-star code is used. Two Padua and the Teramo stellar evolution libraries have been considered

Spitzer observations of the neutron star (ultracompact) X-ray binary (XRB) 4U 0614+091 with the Infrared Array Camera reveal emission of nonthermal origin in the range 3.5-8 μm. The mid-infrared spectrum is well fit by a power law with spectral index of α=-0.57+/-0.04 (where the flux density is Fν~να). Given the ultracompact nature of the binary

The Spectro-Polarimeter for Infrared and Optical Regions (SPINOR) is a new spectro-polarimeter that will serve as a facility instrument for the Dunn Solar Telescope at the National Solar Observatory. This instrument is capable of achromatic polarimetry over a very broad range of wavelengths, from 430 to 1600 nm, allowing for the simultaneous

Through ground-based observations of the Earth's spectrum from California, satellite observations of clouds, and an atmospheric radiative transfer code, we have determined the temporal evolution of the vegetation signature of Earth to characterize one novel approach to this search. We obtained an excellent agreement between models and observations

Ellerman bombs are bright emission features observed in the wings of Hα, usually in the vicinity of magnetic concentrations. Here we show that they can also be detected in the Ca II infrared triplet lines, which are easier to interpret and therefore allow for more detailed diagnostics. We present full Stokes observations of the 849.8 and 854.2 nm