The physical nature such as orbital distribution of asteroids is fundamental to understanding how our solar system has been evolved. The connection between Near-Earth Objects (NEOs) and Earth impactors such as meteorites and fireballs are still under debate, since there is no meteorite orbit whose parent NEO was identified. The orbital distribution of NEOs has been investigated by comprehensive sky surveys including Pan-STARRS (The Panoramic Survey Telescope And Rapid Response System). Here we focus on the Phaethon-Gemind complex detected by Pan-STARRS PS1 Prototype Telescope and our follow-up lightcurve observations.

When a laser beam transmits through a multi-mode fiber, speckles show in the output beam. In this work, we study the laser speckle under static and dynamic scrambling by the histogram and line profile of far-field pattern. The results show that static scrambling has little effect on the intensity distribution. The dynamic scrambling reduces the speckles without changing the line profile. Two possible explanations are proposed.

SHARDS (Survey for High-z Absorption Red & Dead Sources; see Pérez-González et al. 2012) is an optical ultra-deep spectro-photometric survey with OSIRIS-GTC aimed at selecting and studying massive passively evolving galaxies at z=1.0–2.3 in GOODS-North. Nonetheless, the data quality allow a plethora of studies on galaxy populations, including Emission Line Galaxies (ELGs) about which we have started our first science verification project. The selection procedure, measurement and first analysis of ELGs in SHARDS, demonstrate the huge capability of the survey in providing physical information for a large sample of emitters, spanning from local Hα to high-z Lyman-α emitters.

We study the ephemeral regions (ERs) in the quiet Sun observed by the Solar Dynamics Observatory, and find that they can be classified into two types: normal ERs (NERs) and self-cancelled ERs (SERs). We identify 2988 ERs among which there are 190 SERs, about 6.4% of the ERs. The total self-cancelled flux is 9.8% of the total ER flux. We suggest that the self-cancellation of SERs is caused by the submergence of magnetic loops connecting the dipolar patches, without magnetic energy release.

A diverse range of terrestrial planet compositions is believed to exist within known extrasolar planetary systems, ranging from those that are relatively Earth-like to those that are highly unusual, dominated by species such as refractory elements (Al and Ca) or C (as pure C, TiC and SiC)(Bond et al. 2010b). However, all prior simulations have ignored the impact that giant planet migration during planetary accretion may have on the final terrestrial planetary composition. Here, we combined chemical equilibrium models of the disk around five known planetary host stars (Solar, HD4203, HD19994, HD213240 and Gl777) with dynamical models of terrestrial planet formation incorporating various degrees of giant planet migration. Giant planet migration is found to drastically impact terrestrial planet composition by 1) increasing the amount of Mg-silicate species present in the final body; and 2) dramatically increasing the efficiency and amount of water delivered to the terrestrial bodies during their formation process.

A continuous observations near an small active region (AR) NOAA 10976 by the Solar Optical Telescope (SOT) and X-Ray Telescope (XRT) on board the Hinode satellite during Dec. 02 2007 from 15:50 UT to 19:59 UT. We observed that: (a) the filament formed by merging parallel fibrils into a twist structure. (b) the filament faded by reconnecting among its own loop structures, or being stripped into pieces.These process are always preceded by the brightening. (c) for the disappearance of the filament, it has close correlation with the activity, like untwisting or expanding, of its corresponding X-ray bright rope.

The Polar Large Telescope (PLT) project is primarily aimed at undertaking large, wide band synoptic astronomical surveys in the infrared in order to provide critical data to the forthcoming generation of observational facilities such as ALMA, JWST, LSST and the E–ELT, and to complement the observations obtained with them. Sensitive thermal IR surveys beyond 2.3 μm cannot be carried out from any existing ground based observatory and the Antarctic Plateau is the only place on the ground where it can be envisaged, thanks to its unique atmospheric and environmental properties, such as the turbulence profile (image quality), the low opacity and the reduced thermal background emission of the sky. These unique conditions enable high angular resolution wide field surveys in the near thermal infrared (2.3–5 μm). This spectral range is particularly well suited to tackling key astrophysical questions such as: i) investigating the nature of the distant universe, the first generation of stars and the latest stages of stellar evolution, ii) understanding transient phenomena such as gamma ray-bursts and Type Ia supernovae, iii) increasing our knowledge of extra-solar planets. Further instruments may broaden the expected science outcomes of such a 2–4 m class telescope especially for the characterization of galaxies at very large distance to provide new clues in the mysteries of dark matter and energy. Efforts will be made to merge this project with other comparable projects within an international consortium.

To battle light pollution issues, influence the market so that customers request only good lighting. An important factor in doing this is to convince decision makers that light pollution is something the whole society cares about. This article gives an overview of an existing campaign that does this and emphasizes some important factors to consider in your campaign.

Early-type galaxies (ETGs) are thought to be devoid of dust and star-formation, having formed most of their stars at early epochs. We present the detection of the dustiest ETGs in a large-area blind submillimetre survey with Herschel (H-ATLAS, Eales et al.2010), where the lack of pre-selection in other bands makes it the first unbiased survey for cold dust in ETGs. The parent sample of 1087 H-ATLAS galaxies in this study have a ⩾ 5σ detection at 250μm, a reliable optical counterpart to the submillimetre source (Smith et al.2011) and a spectroscopic redshift from the GAMA survey (Driver et al.2011). Additionally, we construct a control sample of 1052 optically selected galaxies undetected at 250μm and matched in stellar mass to the H-ATLAS parent sample to eliminate selection effects. ETGs were selected from both samples via visual classifications using SDSS images. Further details can be found in Rowlands et al. (2012). Physical parameters are derived for each galaxy using the multiwavelength spectral energy distribution (SED) fitting code of da Cunha, Charlot and Elbaz (2008), Smith et al.2012, using an energy balance argument. We investigate the differences between the dusty ETGs and the general ETG population, and find that the H-ATLAS ETGs are more than an order of magnitude dustier than the control ETGs. The mean dust mass of the 42 H-ATLAS ETGs is 5.5 × 107M⊙ (comparable to the dust mass of spirals in our sample), whereas the dust mass of the 233 control ETGs inferred from stacking at optical positions on the 250μm map is (0.8 - 4.0) × 106M⊙ for 25-15 K dust. The average star-formation rate of the H-ATLAS ETGs is 1.0 dex higher than that of control ETGs, and the mean r-band light-weighted age of the H-ATLAS ETGs is 1.8 Gyr younger than the control ETGs. The rest-frame NUV - r colours of the H-ATLAS ETGs are 1.0 magnitudes bluer than the control ETGs, and some ETGs may be transitioning from the blue cloud to the red sequence. Some H-ATLAS ETGs show signs of morphological disturbance and may have undergone recent rejuvenation of their ISM via gas and dust delivered by mergers. It is found that late-type stars cannot produce enough dust to account for that observed in the H-ATLAS ETGs. This indicates that either an external source of dust from mergers is required, a substantial amount of dust grain growth must occur in the ISM, or dust destruction by hot X-ray gas is less efficient than predicted.

We report on the activities preparing long duration stratospheric flights, suitable for CMB (Cosmic Microwave Background) measurements, in the Arctic region. We focus on pathfinder flights, and on two forthcoming experiments to be flown from Longyearbyen (Svalbard islands): the OLIMPO Sunyaev-Zeldovich spectrometer, and the Large-Scale Polarization Explorer (LSPE).

The Antarctic Submillimeter Telescope and Remote Observatory (AST/RO), a 1.7 m diameter offset Gregorian telescope for astronomy and aeronomy studies at wavelengths between 200 and 2000 μm, saw first light in 1995 and operated until 2005. It was the first radio telescope to operate continuously throughout the winter on the Antarctic Plateau. It served as a site testing instrument and prototype for later instruments, as well as executing a wide variety of scientific programs that resulted in six doctoral theses and more than one hundred scientific publications. The South Pole environment is unique among observatory sites for unusually low wind speeds, low absolute humidity, and the consistent clarity of the submillimeter sky. Especially significant are the exceptionally low values of sky noise found at this site, a result of the small water vapor content of the atmosphere. Multiple submillimeter-wave and Terahertz detector systems were in operation on AST/RO, including heterodyne and bolometric arrays. AST/RO's legacy includes comprehensive submillimeter-wave site testing of the South Pole, spectroscopic studies of 492 GHz and 809 GHz neutral atomic carbon and 460 GHz and 806 GHz carbon monoxide in the Milky Way and Magellanic Clouds, and the first detection of the 1.46 THz [N II] line from a ground-based observatory.

Radar instruments play a critical role in studies of Near-Earth Asteroids (NEAs) on two distinct levels: trajectory prediction and physical characterization.

Our team was awarded 108 orbits of Hubble Space Telescope time to obtain parallaxes and photometry of nine metal-poor stars with [Fe/H] < −1.5 dex. The parallaxes are obtained from observations with the Fine Guidance Sensor (FGS 1r; 11 orbits per star) and photometry was obtained with the Advanced Camera for Surveys (one orbit per star). The first data were obtained in October 2008, and the data collection is ongoing. It is anticipated that the observations will be complete in June 2013. Preliminary data reduction has been completed for five of our target stars. The parallax errors vary from 0.12 to 0.16 milli-arcseconds, and the parallaxes are at least an order of magnitude more accurate than existing Hipparcos parallaxes for these stars. The errors in the true distance modulus range from 0.02 to 0.03 mag. Ground-based high-resolution spectra have been analyzed to obtain accurate abundances for three stars. The properties of the two stars with accurate abundances and parallaxes are in excellent agreement with those predicted by stellar evolution models.

The design of five-element digital receiver system is decribed. At first, we analyzed the process of data processing in the receiver system. Then we wrote programs to implement the FIR parallel filter and showed its simulation results. Finally the testing result of the correlation receiver system is demonstrated.

We study radio emission from pulsar wind nebulae (PWNe) considering the observed spatial structure. We assume spherical symmetry of the PWN, and model the evolution of the magnetic field and the particle energy distribution. We do not consider the synchrotron cooling of particles but consider the adiabatic cooling, because we are mostly interested in the radio emission from PWNe. The model is applied to the Crab Nebula and succeeds to reproduce the observed spatially integrated spectrum in radio with a single power-law injection. In our previous work (a one-zone model), in contrast, the integrated spectrum of the Crab Nebula is reproduced by a broken power-law injection of particles. However, the spatial structure in radio is inconsistent with observations and we need a radial velocity profile which is very different from the model by Kennel & Coroniti. Further studies of the spatial structure of PWNe are important to understand the origin of the radio emission from young PWNe.

Light Pollution is a global problem. Some local actions carried out by a network of professional and amateur astronomers in Argentina are changing the way to attack this problem, taking into account measurements, education, public activities, planetarium shows and legislation proposals.

Recent research on global climate changes points to three distinct sources of climate disturbance: anthropogenic; natural changes in the oceans and atmosphere; and irregularities in the solar cycles. One of the most direct ways to survey an exogenous component of the climatic variability is through the measurement of variations in the diameter and shape of the solar disk. At Observatório Nacional/MCTI, Rio de Janeiro, after several years of diameter observation using a CCD Solar Astrolabe, these measurements are now performed by a state-of-the-art Solar Heliometer. The heliometric method is one of the most successful techniques to measure small variations of angles. Its principle has been used for the latest space borne astrometric missions, aiming to milli-arcsecond precision. The success of this method relies in the fact that it minimizes the dependence of angular measurements to the thermal and mechanical stability of the instrument. However in the classic heliometer the objective is split into two halves to which is applied a linear displacement along the cut, thus still leaving room for a residual dependence with the focus, due to non-concentricity of the beams of the two images. The focus variation, as well as the effects brought by the large temperature variations during solar observations, was tackled in the Solar Heliometer by having all optical elements and their niches made on CCZ, and the telescope tube on carbon fiber, both materials of negligible thermal coefficient. Additionally, the measures are made perpendicular to the separation direction and the plate scale can be known at every time from the solar motion itself. We present the results from the first year of measurements, in special exploring the upheaval of solar activity on late 2011.

We examine the innermost 100 parsec scale region of the Seyfert 2 galaxy NGC 1068 using a high spatial resolution X-ray image obtained with the Chandra X-ray Observatory, which allows comparison between X-ray emission clumps, optical narrow line ([OIII]) clouds and sub-arcsecond scale radio jet. Based on the combined X-ray, [OIII], and radio continuum morphology, we identify the locations of intense radio jet-cloud interaction. The [OIII] to soft X-ray ratios show that some of these clouds are strongly affected by shock heating. We estimate that the kinematic luminosity of the jet-driven shocks is 6 × 1038 erg s−1.

We present 3D zero-beta ideal MHD simulations of the solar flare/CME event that occurred in Active Region 11060 on 2010 April 8. The initial magnetic configurations of the two simulations are stable nonlinear force-free field and unstable magnetic field models constructed by Su et al. (2011) using the flux rope insertion method. The MHD simulations confirm that the stable model relaxes to a stable equilibrium, while the unstable model erupts as a CME. Comparisons between observations and MHD simulations of the CME are also presented.