We determine elemental abundances of He, N, O, Ne, S, and Ar in Magellanic Cloud planetary nebulae (PNe) using direct methods and a large set of observed ions, minimizing the need for ionization correction factors. In contrast to prior studies, we find a clear separation between Type I and non-Type I PNe in these low-metallicity environments, and

Available from the Minor Planet Center.

The atlas presents medium-resolution mid-infrared spectra of low- and intermediate mass pre-main sequence objects obtained by the ISOPHOT-S spectrophotometer of the Infrared Space Observatory (ISO) and the Infrared Spectrograph (IRS) of the Spitzer Space Telescope. (2 data files).

This work investigates the cause and effects of extreme changes in synoptic-scale cloud cover operating at daily timescales using a variety of satellite-based and reanalysis data sets. It is found that the largest sudden increases detected in globally averaged cloud cover over the last ten years of satellite-based observations occur following

Models of thermonuclear burning on accreting neutron stars predict different ignition regimes, depending mainly on the mass accretion rate per unit area. For more than three decades, testing these regimes observationally has met with only partial success. I will present recent results from the Fermi-GBM all-sky X-ray burst monitor, which is

We present the Spitzer Extragalactic Representative Volume Survey (SERVS), an 18 deg2 medium-deep survey at 3.6 and 4.5 μm with the postcryogenic Spitzer Space Telescope to ≈2 mJy (AB=23.1) depth of five highly observed astronomical fields (ELAIS-N1, ELAIS-S1, Lockman Hole, Chandra Deep Field South, and XMM-LSS). SERVS is designed to enable the