Abstract Introduction Attitude toward nature and attitude toward environmental protection are two separate but correlated attitudes. Little is known about the two attitudes’ stability/volatility over ...time, despite the practical value of such knowledge. Objectives & method Using longitudinal survey data from 251 adults in a cross-lagged structural equation model, we assessed the degree of spontaneous (i.e., unprompted) change in the two attitudes. We also considered whether such change could provide evidence regarding causal direction; causation could go in either of two directions between the two attitudes, or it could even be bi-directional. Results We corroborated the substantive connection between attitude toward nature and attitude toward environmental protection; however, the absence of change in the attitudes despite the passage of two years disallows reliable statements about causal direction. Conclusion It is possible to protect the environment by encouraging appreciation of nature, but change in attitude toward nature and attitude toward environmental protection may be difficult to achieve with mature individuals.
The color-magnitude relation has been determined for the RDCS J0910+5422 cluster of galaxies at redshift z = 1.106. Cluster members were selected from the Hubble Space Telescope Advanced Camera for ...Surveys (HST ACS) images, combined with ground-based near-IR imaging and optical spectroscopy. The observed early-type color-magnitude relation (CMR) in i' sub(775) - z sub(850) versus z sub(850) shows an intrinsic scatter in color of 0.060 c 0.009 mag, within 1' from the cluster X-ray emission center. Both the elliptical and the S0 galaxies show small scatter about the CMR of 0.042 c 0.010 and 0.044 c 0.020 mag, respectively. From the scatter about the CMR, a mean luminosity-weighted age super( )> 3.3 Gyr (z sub(f) - 3) is derived for the elliptical galaxies, assuming a simple stellar population modeling (single-burst solar metallicity). Strikingly, the S0 galaxies in RDCS J0910+5422 are systematically bluer in i sub(775) - z sub(850), by 0.07 c 0.02 mag, than the ellipticals. The ellipticity distribution as a function of color indicates that the face-on S0s in this particular cluster have likely been classified as elliptical Thus, if anything, the offset in color between the elliptical and S0 populations may be even more significant. The color offset between S0 and E galaxies corresponds to an age difference of -1 Gyr for a single-burst solar-metallicity model. A solar-metallicity model with an exponential decay in star formation will reproduce the offset for an age of 3.5 Gyr; i.e., the S0s have evolved gradually from star-forming progenitors. The early-type population in this cluster appears to be still forming. The blue early-type disk galaxies in RDCS J0910+5422 likely represent the direct progenitors of the more evolved S0s that follow the same red sequence as elliptical galaxies in other clusters. Thirteen red galaxy pairs are observed, and the galaxies associated in pairs constitute 640% of the CMR galaxies in this cluster.
We present Hubble Space Telescope Advanced Camera for Surveys multicolor coronagraphic images of the recently discovered edge-on debris disk around the nearby (~10 pc) M dwarf AU Microscopii. The ...disk is seen between r = 075 and 15'' (7.5-150 AU) from the star. It has a thin midplane with a projected FWHM thickness of 2.5-3.5 AU within r < 50 AU of the star that increases to 6.5-9 AU at r ~ 75 AU. The disk's radial brightness profile is generally flat for r < 15 AU, then decreases gradually (I {proportional to} r-1.8) out to r 43 AU, beyond which it falls rapidly (I {proportional to} r-4.7). Within 50 AU the midplane is straight and aligned with the star, and beyond that it deviates by ~3°, resulting in a bowed appearance that was also seen in ground-based images. Three-dimensional modeling of the disk shows that the inner region (r < 50 AU) is inclined to the line of sight by less than 1° and the outer disk by ~3°. The inclination of the outer disk and moderate forward scattering (g 0.4) can explain the apparent bow. The intrinsic, deprojected FWHM thickness is 1.5-10 AU, increasing with radius. The models indicate that the disk is clear of dust within ~12 AU of the star, in general agreement with the previous prediction of 17 AU based on the infrared spectral energy distribution. The disk is blue, being 60% brighter at B than I relative to the star. One possible explanation for this is that there is a surplus of very small grains compared with other imaged debris disks that have more neutral or red colors. This may be due to the low radiation pressure exerted by the late-type star. Observations at two epochs show that an extended source seen along the midplane is a background galaxy.
We present HST ACS observations of the most distant radio galaxy known, TN J0924-2201 at z = 5.2. This radio galaxy has six spectroscopically confirmed Lya-emitting companion galaxies and appears to ...lie within an overdense region. The radio galaxy is marginally resolved in i sub(775) and z sub(850), showing continuum emission aligned with the radio axis, similar to what is observed for lower redshift radio galaxies. Both the half-light radius and the UV star formation rate are comparable to the typical values found for Lyman break galaxies at z 6 4-5. The Lya emitters are sub-L sub(*) galaxies, with deduced star formation rates of 1-10 M sub( )yr super(-1). One of the Lya emitters is only detected in Lya. Based on the star formation rate of 63 M sub( )yr super(-1) calculated from Lya, the lack of continuum emission could be explained if the galaxy is younger than 62 Myr and is producing its first stars. Observations in V sub(606)i sub(775)z sub(850) were used to identify additional Lyman break galaxies associated with this structure. In addition to the radio galaxy, there are 22 V sub(606) break (z 6 5) galaxies with z sub(850) < 26.5 (5 s), two of which are also in the spectroscopic sample. We compare the surface density of 62 arcmin super(-2) to that of similarly selected V sub(606) dropouts extracted from GOODS and the UDF parallel fields. We find evidence for an overdensity to very high confidence (>99%), based on a counts-in-cells analysis applied to the control field. The excess suggests that the V sub(606) break objects are associated with a forming cluster around the radio galaxy.
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