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We present visual-wavelength photometry and spectroscopy of supernova (SN) 2008S. Based on the low peak luminosity for a SN of M R = −13.9 mag, photometric and spectral evolution unlike that of low-luminosity SNe, a late-time decline rate slower than 56 Co decay, and slow outflow speeds of 600-1000 km s −1 , we conclude that SN 2008S is not a true core-collapse SN and is probably not an electron-capture SN. Instead, we show that SN 2008S more closely resembles a "SN impostor" event like SN 1997bs, analogous to the giant eruptions of luminous blue variables (LBVs). Its total radiated energy was ∼10 47.8 ergs, and it may have ejected 0.05-0.2 M ⊙ in the event. We discover an uncanny similarity between the spectrum of SN 2008S and that of the Galactic hypergiant IRC+10420, which is dominated by narrow Hα, [Ca ii], and Ca ii emission lines formed in an opaque wind. We propose a scenario where the vastly super-Eddington (Γ ≈ 40) wind of SN 2008S partly fails because of reduced opacity due to recombination, as suggested for IRC+10420. The range of initial masses susceptible to eruptive LBV-like mass loss was known to extend down to 20-25 M ⊙ , but estimates for the progenitor of SN 2008S (and the similar NGC 300 transient) may extend this range to 15 M ⊙ . As such, SN 2008S may have implications for the progenitor of SN 1987A.

Cameras attached to small quadrotor aircraft are rapidly becoming a ubiquitous tool for cinematographers, enabling dynamic camera movements through 3D environments. Currently, professionals use these cameras by flying quadrotors manually, a process which requires much skill and dexterity. In this paper, we investigate the needs of quadrotor cinematographers, and build a tool to support video capture using quadrotor-based camera systems. We begin by conducting semi-structured interviews with professional photographers and videographers, from which we extract a set of design principles. We present a tool based on these principles for designing and autonomously executing quadrotor-based camera shots. Our tool enables users to: (1) specify shots visually using keyframes; (2) preview the resulting shots in a virtual environment; (3) precisely control the timing of shots using easing curves; and (4) capture the resulting shots in the real world with a single button click using commercially available quadrotors. We evaluate our tool in a user study with novice and expert cinematographers. We show that our tool makes it possible for novices and experts to design compelling and challenging shots, and capture them fully autonomously.

We present BVRI and unfiltered light curves of 93 Type Ia supernovae (SNe Ia) from the Lick Observatory Supernova Search (LOSS) follow-up program conducted between 2005 and 2018. Our sample consists of 78 spectroscopically normal SNe Ia, with the remainder divided between distinct subclasses (3 SN 1991bg-like, 3 SN 1991T-like, 4 SNe Iax, 2 peculiar, and 3 super-Chandrasekhar events), and has a median redshift of 0.0192. The SNe in our sample have a median coverage of 16 photometric epochs at a cadence of 5.4 d, and the median first observed epoch is ∼4.6 d before maximum B-band light. We describe how the SNe in our sample are discovered, observed, and processed, and we compare the results from our newly developed automated photometry pipeline to those from the previous processing pipeline used by LOSS. After investigating potential biases, we derive a final systematic uncertainty of 0.03 mag in BVRI for our data set. We perform an analysis of our light curves with particular focus on using template fitting to measure the parameters that are useful in standardizing SNe Ia as distance indicators. All of the data are available to the community, and we encourage future studies to incorporate our light curves in their analyses.

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