3D Visualization for Phoenix Mars Lander Science Operations

Planetary surface exploration missions present considerable operational challenges in the form of substantial communication delays, limited communication windows, and limited communication bandwidth. A 3D visualization software was developed and delivered to the 2008 Phoenix Mars Lander (PML) mission. The components of the system include an interactive 3D visualization environment called Mercator, terrain reconstruction software called the Ames Stereo Pipeline, and a server providing distributed access to terrain models. The software was successfully utilized during the mission for science analysis, site understanding, and science operations activity planning. A terrain server was implemented that provided distribution of terrain models from a central repository to clients running the Mercator software. The Ames Stereo Pipeline generates accurate, high-resolution, texture-mapped, 3D terrain models from stereo image pairs. These terrain models can then be visualized within the Mercator environment. The central cross-cutting goal for these tools is to provide an easy-to-use, high-quality, full-featured visualization environment that enhances the mission science team s ability to develop low-risk productive science activity plans. In addition, for the Mercator and Viz visualization environments, extensibility and adaptability to different missions and application areas are key design goals

KOI-1003: A new spotted, eclipsing RS CVn binary in the Kepler field

Using the high-precision photometry from the Kepler space telescope, thousands of stars with stellar and planetary companions have been observed. The characterization of stars with companions is not always straightforward and can be contaminated by systematic and stellar influences on the light curves. Here, through a detailed analysis of starspots and eclipses, we identify KOI-1003 as a new, active RS CVn star---the first identified with data from Kepler. The Kepler light curve of this close binary system exhibits the system's primary transit, secondary eclipse, and starspot evolution of two persistent active longitudes. The near equality of the system's orbital and rotation periods indicates the orbit and primary star's rotation are nearly synchronized ($P_\mathrm{orb} = 8.360613\pm0.000003$ days; $P_\mathrm{rot} \sim 8.23$ days). By assuming the secondary star is on the main sequence, we suggest the system consists of a $1.45^{+0.11}_{-0.19} \ M_\odot$ subgiant primary and a $0.59^{+0.03}_{-0.04} \ M_\odot$ main-sequence companion. Our work gives a distance of $4400 \pm 600$ pc and an age of $t = 3.0^{-0.5}_{+2.0}$ Gyr, parameters which are discrepant with previous studies that included the star as a member of the open cluster NGC 6791.Comment: 21 pages, 19 figures, accepted to Ap

Close-up of primary and secondary asteroseismic CoRoT targets and the ground-based follow-up observations

To optimise the science results of the asteroseismic part of the CoRoT satellite mission a complementary simultaneous ground-based observational campaign is organised for selected CoRoT targets. The observations include both high-resolution spectroscopic and multi-colour photometric data. We present the preliminary results of the analysis of the ground-based observations of three targets. A line-profile analysis of 216 high-resolution FEROS spectra of the delta Sct star HD 50844 reveals more than ten pulsation frequencies in the frequency range 5-18 c/d, including possibly one radial fundamental mode (6.92 c/d). Based on more than 600 multi-colour photometric datapoints of the beta Cep star HD180642, spanning about three years and obtained with different telescopes and different instruments, we confirm the presence of a dominant radial mode nu1=5.48695 c/d, and detect also its first two harmonics. We find evidence for a second mode nu2=0.3017 c/d, possibly a g-mode, and indications for two more frequencies in the 7-8 c/d domain. From Stromgren photometry we find evidence for the hybrid delta Sct/gamma Dor character of the F0 star HD 44195, as frequencies near 3 c/d and 21 c/d are detected simultaneously in the different filters.Comment: 7 pages, 6 figures, HELAS II International Conference "Helioseismology, Asteroseismology and MHD Connections", 2008, J.Phys.: Conf. Ser. 118, 01207

Detection of gravity modes in the massive binary V380 Cyg from Kepler spacebased photometry and high-resolution spectroscopy

We report the discovery of low-amplitude gravity-mode oscillations in the massive binary star V380 Cyg, from 180 d of Kepler custom-aperture space photometry and 5 months of high-resolution high signal-to-noise spectroscopy. The new data are of unprecedented quality and allowed to improve the orbital and fundamental parameters for this binary. The orbital solution was subtracted from the photometric data and led to the detection of periodic intrinsic variability with frequencies of which some are multiples of the orbital frequency and others are not. Spectral disentangling allowed the detection of line-profile variability in the primary. With our discovery of intrinsic variability interpreted as gravity mode oscillations, V380 Cyg becomes an important laboratory for future seismic tuning of the near-core physics in massive B-type stars.Comment: 5 pages, 4 figures, 2 tables. Accepted for publication in MNRAS Letter

Observational asteroseismology of hot subdwarf stars

Hot subdwarf stars are particularly challenging for asteroseismology due to their rapid pulsation periods, intrinsic faintness and relative rarity both in the field and in clusters. These features have ensured that the preferred method of observation up to now has been white-light photometry, and all asteroseismological solutions to date have been made by model fitting of the frequency spectrum. Several attempts have been made to perform asteroseismology using time-resolved spectroscopy on the brightest of these stars, but with modest results. A few attempts at simultaneous multi-color photometry have also been made to identify modes with the amplitude ratio method. We will review the most recent observational results and progress in improving the observational methods for ground-based asteroseismology of these compact pulsators.Comment: 8 pages, to appear in Astronomische Nachrichten, Vol. 331, 102

Analysis of MERCATOR data Part I: variable B stars

We re-classified 31 variable B stars which were observed more than 50 times in the Geneva photometric system with the P7 photometer attached to the MERCATOR telescope (La Palma) during its first 3 years of scientific observations. HD89688 is a possible beta Cephei/slowly pulsating B star hybrid and the main mode of the COROT target HD180642 shows non-linear effects. The Maia candidates are re-classified as either ellipsoidal variables or spotted stars. Although the mode identification is still ongoing, all the well-identified modes so far have a degree l = 0, 1 or 2.Comment: 4 pages, 3 figures. To appear in: Proceedings of JENAM 2005 'Distant worlds', Communications in Asteroseismolog

Revealing the Nature of Extreme Coronal-line Emitter SDSS J095209.56+214313.3

Extreme coronal-line emitter (ECLE) SDSSJ095209.56+214313.3, known by its strong, fading, high ionization lines, has been a long standing candidate for a tidal disruption event, however a supernova origin has not yet been ruled out. Here we add several new pieces of information to the puzzle of the nature of the transient that powered its variable coronal lines: 1) an optical light curve from the Lincoln Near Earth Asteroid Research (LINEAR) survey that serendipitously catches the optical flare, and 2) late-time observations of the host galaxy with the Swift Ultraviolet and Optical Telescope (UVOT) and X-ray telescope (XRT) and the ground-based Mercator telescope. The well-sampled, $\sim10$-year long, unfiltered LINEAR light curve constrains the onset of the flare to a precision of $\pm5$ days and enables us to place a lower limit on the peak optical magnitude. Difference imaging allows us to estimate the location of the flare in proximity of the host galaxy core. Comparison of the \textsl{GALEX} data (early 2006) with the recently acquired Swift UVOT (June 2015) and Mercator observations (April 2015) demonstrate a decrease in the UV flux over a $\sim 10$ year period, confirming that the flare was UV-bright. The long-lived UV-bright emission, detected 1.8 rest-frame years after the start of the flare, strongly disfavors a SN origin. These new data allow us to conclude that the flare was indeed powered by the tidal disruption of a star by a supermassive black hole and that TDEs are in fact capable of powering the enigmatic class of ECLEs.Comment: Submitted to Ap

Male sperm whale acoustic behavior observed from multipaths at a single hydrophone

Sperm whales generate transient sounds (clicks) when foraging. These clicks have been described as echolocation sounds, a result of having measured the source level and the directionality of these signals and having extrapolated results from biosonar tests made on some small odontocetes. The authors propose a passive acoustic technique requiring only one hydrophone to investigate the acoustic behavior of free-ranging sperm whales. They estimate whale pitch angles from the multipath distribution of click energy. They emphasize the close bond between the sperm whale’s physical and acoustic activity, leading to the hypothesis that sperm whales might, like some small odontocetes, control click level and rhythm. An echolocation model estimating the range of the sperm whale’s targets from the interclick interval is computed and tested during different stages of the whale’s dive. Such a hypothesis on the echolocation process would indicate that sperm whales echolocate their prey layer when initiating their dives and follow a methodic technique when foraging

LANDSAT D position determination and correction study

An assessment of accuracy of the knowledge of LANDSAT D spacecraft ephemeris data, an evaluation of the impact of expected attitude and alignment accuracies and analysis of the various options for the combining of precision ephemeris and attitude data with scene image data are provided. The potential geometric correction system in order to determine overall system costs and impact on other system elements is characterized