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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The surface of Ariel displays regions that were resurfaced in the geologically recent past. Some of these regions include large chasmata that exhibit evidence for flexure. To estimate Ariel's heat fluxes, we analyzed flexure associated with the Pixie Group of chasmata, including Pixie, Kewpie, Brownie, Kra, Sylph, and an unnamed chasma, and the Kachina Group of chasmata, which includes Kachina Chasmata. We analyzed topography of these chasmata using digital elevation models developed for this work. Our results indicate that Ariel's elastic thicknesses range between 4.4 ± 0.7 km and 11.4 ± 1.4 km across the imaged surface. The younger Kachina Group has a relatively low elastic thickness of 4.4 ± 0.7 km compared to most chasmata in the older Pixie Group (4.1 ± 0.3 km to 11.4 ± 1.4 km). A pure H2O ice lithosphere would correspond to heat fluxes ranging from 17 to 46 mW m−2 for the Kachina Group and from 6 to 40 mW m−2 for the Pixie Group. Alternatively, if NH3 hydrates are present in Ariel's lithosphere, then the estimated heat fluxes are lower, ranging from 3 to 18 mW m−2 for the Kachina Group and from 1 to 16 mW m−2 for the Pixie Group. These results indicate that accounting for NH3 hydrates in the lithosphere substantially alters the resulting heat flux estimates, which could have important implications for understanding the lithospheric properties of other icy bodies where NH3-bearing species are expected to be present in their lithospheres. Our results are consistent with Ariel experiencing tidal heating generated from mean motion resonances with neighboring satellites in the past, in particular Titania and Miranda.

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The 27 satellites of Uranus are enigmatic, with dark surfaces coated by material that could be rich in organics. Voyager 2 imaged the southern hemispheres of Uranus’s five largest “classical” moons—Miranda, Ariel, Umbriel, Titania, and Oberon, as well as the largest ring moon, Puck—but their northern hemispheres were largely unobservable at the time of the flyby and were not imaged. Additionally, no spatially resolved data sets exist for the other 21 known moons, and their surface properties are essentially unknown. Because Voyager 2 was not equipped with a near-infrared mapping spectrometer, our knowledge of the Uranian moons’ surface compositions, and the processes that modify them, is limited to disk-integrated data sets collected by ground- and space-based telescopes. Nevertheless, images collected by the Imaging Science System on Voyager 2 and reflectance spectra collected by telescope facilities indicate that the five classical moons are candidate ocean worlds that might currently have, or had, liquid subsurface layers beneath their icy surfaces. To determine whether these moons are ocean worlds, and to investigate Uranus’s ring moons and irregular satellites, close-up observations and measurements made by instruments on board a Uranus orbiter are needed.

In 1966, while examining some of the earliest images of the lunar surface, researchers identified several dark features, which were postulated to be cave entrances (Heacock et al., 1966). Later that year, Halliday (1966) further mused over the existence of lunar caves and briefly discussed their potential importance for future human

We present BVRI and unfiltered (Clear) light curves of 70 stripped-envelope supernovae (SESNe), observed between 2003 and 2020, from the Lick Observatory Supernova Search (LOSS) follow-up program. Our SESN sample consists of 19 spectroscopically normal SNe Ib, two peculiar SNe Ib, six SNe Ibn, 14 normal SNe Ic, one peculiar SN Ic, ten SNe Ic-BL, 15 SNe IIb, one ambiguous SN IIb/Ib/c, and two superluminous SNe. Our follow-up photometry has (on a per-SN basis) a mean coverage of 81 photometric points (median of 58 points) and a mean cadence of 3.6 d (median of 1.2 d). From our full sample, a subset of 38 SNe have pre-maximum coverage in at least one passband, allowing for the peak brightness of each SN in this subset to be quantitatively determined. We describe our data collection and processing techniques, with emphasis toward our automated photometry pipeline, from which we derive publicly available data products to enable and encourage further study by the community. Using these data products, we derive host-galaxy extinction values through the empirical colour evolution relationship and, for the first time, produce accurate rise-time measurements for a large sample of SESNe in both optical and infrared passbands. By modeling multiband light curves, we find that SNe Ic tend to have lower ejecta masses and lower ejecta velocities than SNe Ib and IIb, but higher 56Ni masses.

Uranus’s moon Miranda has a complex surface reflecting multiple episodes of activity. We estimated the heat flux near Inverness Corona, the youngest terrain on Miranda ( 100 − 100 + 400 Ma), to gain insight into recent endogenic resurfacing. We modeled flexure associated with Argier Rupes, which separates Inverness from the Cratered Terrain. Our results indicate an elastic thickness of 2.2–3.1 km and a heat flux of 35–140 mW m−2 in this region, assuming Miranda’s lithosphere is composed of pure H2O ice without porosity. Because the formation of the bounding flexure that we analyzed followed the formation of Argier Rupes, our results indicate that Miranda experienced high heat flux in the past 100 − 100 + 400 Ma. These results are also consistent with heating from a past resonance, possibly an Ariel–Umbriel 5:3 mean motion resonance, estimated to have generated heat fluxes >100 mW m−2 on Miranda. However, if Miranda instead has a porous lithosphere, our heat flux estimates are lower: 34–135 mW m−2 for 5% porosity, 29–114 mW m−2 for 15% porosity, and 20–81 mW m−2 for 25% porosity. Alternatively, if Miranda’s lithosphere includes NH3-hydrates, then our are estimates are even lower, 7–56 mW m−2 without porosity. These estimates decrease further when assuming NH3-hydrates and porosity: 7–54 mW m−2 for 5% porosity, 6–46 mW m−2 for 15% porosity, and 4–32 mW m−2 for 25% porosity. Better constraints on Miranda’s heat fluxes require more information on its ice shell properties.