Orbital evolution of P\v{r}\'{i}bram and Neuschwanstein

The orbital evolution of the two meteorites P\v{r}\'{i}bram and Neuschwanstein on almost identical orbits and also several thousand clones were studied in the framework of the N-body problem for 5000 years into the past. The meteorites moved on very similar orbits during the whole investigated interval. We have also searched for photographic meteors and asteroids moving on similar orbits. There were 5 meteors found in the IAU MDC database and 6 NEAs with currently similar orbits to P\v{r}\'{i}bram and Neuschwanstein. However, only one meteor 161E1 and one asteroid 2002 QG46 had a similar orbital evolution over the last 2000 years.Comment: 7 pages, 2 figures, 3 table

Meteor showers of comet C/1917 F1 Mellish

December Monocerotids and November Orionids are weak but established annual meteor showers active throughout November and December. Analysis of a high quality orbits subset of the SonotaCo video meteor database shows that the distribution of orbital elements, geocentric velocity and also the orbital evolution of the meteors and potential parent body may imply a common origin for these meteors coming from the parent comet C/1917 F1 Mellish. This is also confirmed by the physical properties and activity of these shower meteors. An assumed release of meteoroids at the perihelion of the comet in the past and the sky-plane radiant distribution reveal that the December Monocerotid stream might be younger than the November Orionids. A meteoroid transversal component of ejection velocity at the perihelion must be larger than 100 m/s. A few authors have also associated December Canis Minorids with the comet C/1917 F1 Mellish. However, we did not find any connection.Comment: 11 pages, 11 figures and 5 table

Pre-discovery observations of CoRoT-1b and CoRoT-2b with the BEST survey

The BEST wide-angle telescope installed at the Observatoire de Haute-Provence and operated in remote control from Berlin by the Institut fuer Planetenforschung, DLR, has observed the CoRoT target fields prior to the mission. The resulting archive of stellar photometric lightcurves is used to search for deep transit events announced during CoRoT's alarm-mode to aid in fast photometric confirmation of these events. The "initial run" field of CoRoT (IRa01) has been observed with BEST in November and December 2006 for 12 nights. The first "long run" field (LRc01) was observed from June to September 2005 for 35 nights. After standard CCD data reduction, aperture photometry has been performed using the ISIS image subtraction method. About 30,000 lightcurves were obtained in each field. Transits of the first detected planets by the CoRoT mission, CoRoT-1b and CoRoT-2b, were found in archived data of the BEST survey and their lightcurves are presented here. Such detections provide useful information at the early stage of the organization of follow-up observations of satellite alarm-mode planet candidates. In addition, no period change was found over ~4 years between the first BEST observation and last available transit observations.Comment: AJ, accepte

Tidal disruption of NEAs - a case of P\v{r}\'ibram

This work studies the dynamical evolution of a possible meteor stream along the orbit of the P\v{r}\'{i}bram meteorite, which originated in the tidal disruption of the putative rubble-pile-like parent body during a close approach to the Earth. We assumed the disruption at the time when the ascending or descending node of the parent orbit was close to the Earth's orbit. In the last 5000 years, the P\v{r}\'{i}bram orbit has crossed the Earth orbit twice. It happened about 4200 years and 3300 years ago. In both cases, we modeled the release of particles from the simplified model of rotating asteroid, and traced their individual orbital evolution to the current date. It takes several hundred years to spread released meteoroids along the entire orbit of the parent body. Even today, the stream would be relatively narrow. Considering a model parent body with physical parameters of the asteroid Itokawa, the complete disintegration of the object produced 3.8$\times10^{11}$ meteoroid particles with diameter $\geq$ 1\,cm. The meteor activity observed from the Earth is revealed and justification of follow-up observation during suggested activity of the shower in the first two weeks of April is discussed. The Earth's tidal forces would disintegrate a fraction of NEA population into smaller objects. We evaluate the upper limit of mass of disintegrated asteroids within the mean NEA lifetime and the contribution of disrupted matter to the size distribution of the NEA.Comment: 8 pages, 10 figure

Observational Constraints on the Catastrophic Disruption Rate of Small Main Belt Asteroids

We have calculated 90% confidence limits on the steady-state rate of catastrophic disruptions of main belt asteroids in terms of the absolute magnitude at which one catastrophic disruption occurs per year (HCL) as a function of the post-disruption increase in brightness (delta m) and subsequent brightness decay rate (tau). The confidence limits were calculated using the brightest unknown main belt asteroid (V = 18.5) detected with the Pan-STARRS1 (Pan-STARRS1) telescope. We measured the Pan-STARRS1's catastrophic disruption detection efficiency over a 453-day interval using the Pan-STARRS moving object processing system (MOPS) and a simple model for the catastrophic disruption event's photometric behavior in a small aperture centered on the catastrophic disruption event. Our simplistic catastrophic disruption model suggests that delta m = 20 mag and 0.01 mag d-1 < tau < 0.1 mag d-1 which would imply that H0 = 28 -- strongly inconsistent with H0,B2005 = 23.26 +/- 0.02 predicted by Bottke et al. (2005) using purely collisional models. We postulate that the solution to the discrepancy is that > 99% of main belt catastrophic disruptions in the size range to which this study was sensitive (100 m) are not impact-generated, but are instead due to fainter rotational breakups, of which the recent discoveries of disrupted asteroids P/2013 P5 and P/2013 R3 are probable examples. We estimate that current and upcoming asteroid surveys may discover up to 10 catastrophic disruptions/year brighter than V = 18.5.Comment: 61 Pages, 10 Figures, 3 Table

Brightness variation distributions among main belt asteroids from sparse light curve sampling with Pan-STARRS 1

The rotational state of asteroids is controlled by various physical mechanisms including collisions, internal damping and the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect. We have analysed the changes in magnitude between consecutive detections of approximately 60,000 asteroids measured by the PanSTARRS 1 survey during its first 18 months of operations. We have attempted to explain the derived brightness changes physically and through the application of a simple model. We have found a tendency toward smaller magnitude variations with decreasing diameter for objects of 1 < D < 8 km. Assuming the shape distribution of objects in this size range to be independent of size and composition our model suggests a population with average axial ratios 1 : 0.85 \pm 0.13 : 0.71 \pm 0.13, with larger objects more likely to have spin axes perpendicular to the orbital plane.Comment: 10 pages, 10 figures, accepted by MNRA

Extrasolar Planet Transits Observed at Kitt Peak National Observatory

We obtained J-, H- and JH-band photometry of known extrasolar planet transiting systems at the 2.1-m Kitt Peak National Observatory Telescope using the FLAMINGOS infrared camera between October 2008 and October 2011. From the derived lightcurves we have extracted the mid-transit times, transit depths and transit durations for these events. The precise mid-transit times obtained help improve the orbital periods and also constrain transit-time variations of the systems. For most cases the published system parameters successfully accounted for our observed lightcurves, but in some instances we derive improved planetary radii and orbital periods. We complemented our 2.1-m infrared observations using CCD z'-band and B-band photometry (plus two Hydrogen Alpha filter observations) obtained with the Kitt Peak Visitor's Center telescope, and with four H-band transits observed in October 2007 with the NSO's 1.6-m McMath-Pierce Solar Telescope. The principal highlights of our results are: 1) our ensemble of J-band planetary radii agree with optical radii, with the best-fit relation being: (Rp/R*)J = 0.0017 + 0.979 (Rp/R*)optical, 2) We observe star spot crossings during the transit of WASP-11/HAT-P-10, 3) we detect star spot crossings by HAT-P-11b (Kepler-3b), thus confirming that the magnetic evolution of the stellar active regions can be monitored even after the Kepler mission has ended, and 4) we confirm a grazing transit for HAT-P-27/WASP-40. In total we present 57 individual transits of 32 known exoplanet systems.Comment: 33 pages, 6 figures, accepted in Publications of the Astronomical Society of the Pacifi