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Two nearby black holes are the most massive yet found, with masses--of around ten billion solar masses--considerably greater than predicted by conventional methods relating black-hole mass with the stellar velocity dispersion and bulge luminosity of the host galaxy. New 'record' for black hole size At 6.3 billion solar masses, the central black hole in the supergiant elliptical galaxy M87 has been regarded as the most massive known black hole in the Universe for more than three decades. This paper reports two galaxies containing black holes that exceed that figure. NGC 3842 has a central black hole of 9.7 billion solar masses, and NGC 4889 has one of comparable or greater mass. Indications of such massive black holes have existed in the early Universe from luminous quasars but have eluded our detection; these results are the first to connect these early massive black holes to host galaxies in the nearby Universe. Observational work conducted over the past few decades indicates that all massive galaxies have supermassive black holes at their centres. Although the luminosities and brightness fluctuations of quasars in the early Universe suggest that some were powered by black holes with masses greater than 10 billion solar masses.sup.1,2, the remnants of these objects have not been found in the nearby Universe. The giant elliptical galaxy Messier 87 hosts the hitherto most massive known black hole, which has a mass of 6.3 billion solar masses.sup.3,4. Here we report that NGC 3842, the brightest galaxy in a cluster at a distance from Earth of 98 megaparsecs, has a central black hole with a mass of 9.7 billion solar masses, and that a black hole of comparable or greater mass is present in NGC 4889, the brightest galaxy in the Coma cluster (at a distance of 103 megaparsecs). These two black holes are significantly more massive than predicted by linearly extrapolating the widely used correlations between black-hole mass and the stellar velocity dispersion or bulge luminosity of the host galaxy.sup.5,6,7,8,9. Although these correlations remain useful for predicting black-hole masses in less massive elliptical galaxies, our measurements suggest that different evolutionary processes influence the growth of the largest galaxies and their black holes., Author(s): Nicholas J. McConnell [sup.1] , Chung-Pei Ma [sup.1] , Karl Gebhardt [sup.2] , Shelley A. Wright [sup.1] , Jeremy D. Murphy [sup.2] , Tod R. Lauer [sup.3] , James [...]

Author(s): Paul Kalas (corresponding author) [1]; James R. Graham [1]; Mark Clampin [2] The Sun and >15 per cent of nearby stars are surrounded by dusty disks that must be [...]

We present adaptive optics (AO) observations of Io taken with the W.M. Keck II telescope on 18 December 2001 (UT) before the satellite went into eclipse, and while it was in Jupiter's shadow. Making these kind of Io-in-eclipse observations, as well as the associated data reduction and analysis are challenging; hence one focus of the paper is to explain the methods and tools used for these data sets. For the sunlit images Io itself was used as the wavefront reference source, while nearby Ganymede was used as reference 'star' when Io was in eclipse. Observations were obtained in K'-, L'-, and M-bands. The sunlit images have been deconvolved using MISTRAL. The Io-in-eclipse data were deconvolved with IDAC and MISTRAL. The former gives better results, both in absolute photometry and in matching the original images. We determined the flux densities of the hot spots from the original Io-in-eclipse data with StarFinder, as well as from the deconvolved images by integrating the intensity over the relevant areas. We determined the highly anisoplanatic PSF via a FFT method from the original data, and used this in StarFinder and as a starting PSF for IDAC and MISTRAL. We derived temperatures and areal coverage of all 19 spots detected in both K'- and L'-band images of Io-in-eclipse. We also determined temperatures and areal coverage of the hot spots visible on the L'- and M-band images of sunlit Io. Most volcanoes contain a compact hot 'core' ([??] 10 [km.sup.2] at 600-800 K) within a larger area at lower temperatures (e.g., ~[10.sup.2] -[10.sup.4] [km.sup.2] at 300-500 K). The total heat flow contributed by these active volcanoes is 0.2 W [m.sup.-2], ~8% of the average global heat flow measured at 5-20 [micro]m by Veeder et al. [J. Geophys. Res. 99 (1994) 17095]. Keywords: Io: Eclipse: Adaptive optics; PSF

We report the discovery of the forbidden electronic [a.sup.1] [DELTA] [right arrow] [X.sup.3] [[SIGMA].sup.-] transition of the SO radical on Io at 1.7 [micro]m with the W. M. Keck II telescope on 24 September 1999 (UT), while the satellite was eclipsed by Jupiter. The shape of the SO emission band suggests a rotational temperature of ~1000 K; i.e., the gas is extremely hot. We interpret the observed emission rate of ~2 x [10.sup.27] photons [s.sup.-1] to be caused by SO molecules in the excited [a.sup.1] [DELTA] state being directly ejected from the vent at a thermodynamic quenching temperature of ~1500 K, assuming a SO/S[O.sub.2] abundance ratio of ~0.1 and a total venting rate of ~[10.sup.31] molecules [s.sup.-1] (Strobel and Wolven 2001, Astrophys. Space Sci. 277, 1-17). The shape of our complete (1.6-2.5 [micro]m) spectrum suggests that the volcano Loki contains a small (~2 [km.sup.2]) hot spot at 960 [+ or -] 12 K, as well as a larger (~50 [km.sup.2]) area at 640 [+ or -] 5 K. Key Words: Io; infrared observations; volcanism; atmosphere composition; atmosphere structure.

We report the first ground-based detection of Saturn's G ring, together with the first infrared images of the E ring. The data were taken during the May and August 1995 ring plane crossings using the W. M. Keck telescope at a wavelength of 2.26 [[micro]meter]. The E ring's radial and vertical structure is found to be generally consistent with previous results from Voyager and Earth-based observatories; it has a brightness peak near the orbit of Enceladus and extends outward to [approximately]6 [R.sub.s] (Saturn radii). The E ring is [approximately]40% fainter at 2.26 [[micro]meter] than in the visual, confirming and extending previous reports that it is very blue in color. The G ring is located at 2.8 [R.sub.s] and is unresolved in vertical thickness. Its reflected intensity is similar to that found in the comparable Voyager image, implying that the ring is neutral in color from the visual to the infrared.

The W. M. Keck telescope was used to observe the impact of comet Shoemaker-Levy 9 (SL9) fragment R at a wavelength of 2.3 micrometers on 21 July 1994. The data showed three outbursts. The first flash lasted about 40 seconds and was followed 1 minute after its peak by a second flash that lasted about 3 minutes. A third, longer lasting flare began 6 minutes after the first flash and lasted for 1 0 minutes. At its maximum brightness, the flare outshone Jupiter. The two short flashes are probably associated with the initial meteor trail and the subsequent fireball, respectively. The bright flare occurred when the impact site rotated into view. These data show that the explosion ejected material at least 1300 kilometers above the visible cloud tops. The luminosity of the impact site during the long bright flare was probably maintained by the release of gravitational potential energy, as this material fell back onto the lower atmosphere., On 16 July 1994, the first fragment of comet Shoemaker-Levy 9 (SL9), fragment A, crashed into jupiter, soon followed by fragments B through W. The observations presented here, which consist [...]

An analysis of molecular processes involved in small intestine epithelial growth confirms an intricate and temporally associated form of gene expression inside the small intestinal epithelium upon refeeding, and establishes a link between the differentiation mechanisms and intestinal development. Modifications in c-fos and c-jun expression demonstrate the nitrogenic response to refeeding that takes place inside the crypt compartment.

While more and more long-period giant planets are discovered by direct imaging, the distribution of planets at these separations (≳5 AU) has remained largely uncertain, especially compared to planets in the inner regions of solar systems probed by RV and transit techniques. The low frequency, the detection challenges, and heterogeneous samples make determining the mass and orbit distributions of directly imaged planets at the end of a survey difficult. By utilizing Monte Carlo methods that incorporate the age, distance, and spectral type of each target, we can use all stars in the survey, not just those with detected planets, to learn about the underlying population. We have produced upper limits and direct measurements of the frequency of these planets with the most recent generation of direct imaging surveys. The Gemini NICI Planet-Finding Campaign observed 220 young, nearby stars at a median H-band contrast of 14.5 magnitudes at 1", representing the largest, deepest search for exoplanets by the completion of the survey. The Gemini Planet Imager Exoplanet Survey is in the process of surveying 600 stars, pushing these contrasts to a few tenths of an arcsecond from the star. With the advent of large surveys (many hundreds of stars) using advanced planet-imagers we gain the ability to move beyond measuring the frequency of wide-separation giant planets and to simultaneously determine the distribution as a function of planet mass, semi-major axis, and stellar mass, and so directly test models of planet formation and evolution. [ABSTRACT FROM AUTHOR]

We imaged the jovian ring system at a wavelength of 2.27 [[micro]meter] with the 10-m W. M. Keck telescope on August 14 and 15, 1997, when the ring plane was almost edge-on (opening angle [Beta] = 0.17 [degrees]) and near opposition (phase angle [Alpha] [approximately equal to] 1.1 [degrees]). The resolution in the images is 0.6[double prime] = 0.025 [R.sub.J]. We obtained the first images of the jovian halo and gossamer ring in back-scattered light, and the best ground-based images to date of Jupiter's main ring. The main ring is radially confined between 1.70 and 1.82 [R.sub.J] (where 1 [R.sub.J] = 71398 km), with a maximum (after inversion) at 1.79 [R.sub.J], in agreement with the Voyager findings. The halo extends inward from the main ring (at 1.71 [R.sub.J]) down to 1.40 [R.sub.J], apparently bounded by the locations of Lorentz resonances. Roughly 50% of the halo's intensity originates from a region within [approximately]700 km from the equatorial plane, although it is visible up to [approximately]10,000 km above and below the plane. Although the vertical extent agrees with Voyager findings, the halo's intensity relative to that of the main ring in the Keck images is much less than in forward-scattered Voyager images, which we attribute to a predominance of micrometer-sized particles, which scatter visible light preferentially in the forward direction. The gossamer ring is found to have two components, with steep dropoffs in brightness at the orbits of Amalthea and Thebe. The first, Amalthea's gossamer ring, is visible between the main ring's periphery and [approximately]2.55 [R.sub.J]; it is relatively uniform in brightness and has a vertical thickness (FWHM) of 0.06 [R.sub.J], clearly broader than the FWHM of the main ring (0.045 [R.sub.J]) and the image resolution. The other component, Thebe's gossamer ring, is a factor of five fainter than Amalthea's ring and about twice as broad vertically (FWHM [approximately equal to] 0.12 [R.sub.J]). This ring extends outward to 3.11 [R.sub.J], but additional material is visible, albeit barely, out to [approximately]3.6 [R.sub.J], near the edge of our images. The vertical extent of both the Thebe and Amalthea rings decreases with decreasing distance to the planet. Key Words: Jupiter; ring; infrared; dust; dynamics; photometry.

The Gemini Planet Imager (GPI) is a high contrast coronagraph designed to directly image exoplanets and circumstellar disks. GPI includes a polarimetry mode designed to characterize dust grains and enhance the contrast of scattered, polarized light by a factor of 100. Reflections and birefringence of optics within the optical train induce a polarization signature that needs to be measured a priori and calibrated out during data reduction. Here we report on the results of an extensive laboratory characterization campaign of the polarimetry mode. The linear instrumental polarization has been measured in 4 GPI passbands and found to be between 3.5 ± 0.3 % at 1.0 micron and 1.1 ± 0.3 % at 2.0 microns. Modulation efficiency has been measured to be 94% at 1.0 micron increasing to 97% at 2.0 microns. Stability has been shown to better than 0.6% over timescales of ~ 3 months and over cool down cycles. The tests show that GPI passes all polarimetry design requirements and should be able to measure circumstellar disk linear polarization to 1% accuracy. [ABSTRACT FROM PUBLISHER]

Direct imaging and spectroscopy of exoplanets is a key element for understanding planet formation and migration. Such direct detections and characterizations remains technologically challenging, since a very high contrast ratio and small angular separation are involved, and futhermore speckle noise limits the high-contrast imaging performance. We further discuss a speckle subtraction and suppression technique that fully takes advantage of spectral and time-domain information on quasi-static speckles to measure the highest-fidelity photometry as well as accurate astrometry of detected companions. [ABSTRACT FROM PUBLISHER]

We present preliminary measurements of the central black hole mass MBH, and stellar mass-to-light ratio M*/LR, in the Brightest Cluster Galaxy of Abell 2162 (A2162–BCG), using integral-field unit (IFU) data from OSIRIS on Keck 2 with laser guide star adaptive optics (LGS-AO). Our results demonstrate early success in an ongoing effort to obtain stellar dynamical measurements of MBH in nine BCGs using ground-based AO. [ABSTRACT FROM PUBLISHER]