Together with other cosmological probes, observations of the cosmic microwave background (CMB) radiation have been used to determine standard cosmological parameters with high precision. Much more information is needed, however, to understand the link between the outlandish Lambda dominated-CDM Universe and fundamental physics. In the first part of the talk, I will describe several ongoing CMB experiments targeting the high-l power spectrum and the B-mode polarization anisotropies. These ground- and balloon-based experiments highly compliment the WMAP satellite in survey parameters and science goals. In the second part of the talk, I will describe the CMB detector development efforts at JPL/Caltech, with emphasis on the antenna-coupled transition edge sensors (TES), a technology now reaching maturity. The next generation CMB experiments enabled by this new technology will look even deeper in the B-mode polarization to pursue the imprints of the primordial gravitational background radiation left by Inflation.

The Laser Interferometer Gravitational-wave Observatory (LIGO) has built three multi-km scale interferometers, designed to search for gravitational waves (GW). One of the targets for these searches is the stochastic GW background, whose existence is expected both due to cosmological and due to astrophysical sources. We discuss the status of LIGO, the most recent results of the search for stochastic GW radiation with LIGO interferometers, and the implications of these results for some of the theoretical models of stochastic GW background.

Astrophysical observations indicate that at least 90% of the mass of any galaxy -- and as much as 98% of the mass of the universe -- is in the form of matter that cannot be seen. Furthermore, most of this matter isn't even made from protons and neutrons -- or any other known particles. What could this matter be and how can we find out? Perhaps the best motivated possibility is weakly interacting massive particles (WIMPs) left over from the Big Bang; these particles naturally arise, for example, under supersymmetry. Detection of these particles requires exquisite
rejection of interactions from natural radioactivity, as achieved using the CDMS experiment's cryogenically cooled crystals of silicon or germanium with thin-film sensors to detect both ionization and athermal phonons. Operation of these novel detectors and the prospects for discovering what's the matter in the universe will be discussed.

I will present observational constraints on the formation and evolution of two separate components of late-type spiral galaxies, their nuclear star clusters and their disks. Both projects stem from HST observations of nearby, edge-on galaxies. First, I will show nuclear clusters that have both compact (<10 pc) disk and spheroidal components. These compact disk components are aligned with the major axis of the galaxy disk and have younger stellar populations than the spheroidal components. Combined with spectroscopic evidence of multiple stellar populations, these observations strongly suggest that nuclear star clusters form in situ, with episodic star formation occurring in compact disks. Second, I will examine the vertical structure of six low mass, late-type spiral galaxies. By using resolved stars to track populations of different ages, I will demonstrate that older populations have larger disk scale heights. The metallicity of the oldest population is Z ~ -1, similar to the Milky Way thick disk, and does not vary with height above the disk. These observations require both disk heating and merging to play a role in the formation of these disks. Finally, I will present the preliminary detection of a low-metallicity stellar halo in one of these galaxies, NGC 4244.

Clusters of galaxies form from the highest peaks in the primordial spectrum of density perturbations generated by inflation in the early universe. They are the most massive virialized structures in the universe, and as such are rare objects. The number density of galaxy clusters as a function of mass and redshift is strongly dependent on a number of cosmological parameters.

I will present results from a study of sophisticated synthetic Sunyaev-Zel'dovich effect (SZE) galaxy cluster surveys with both large sky coverage and high angular resolution. These surveys are generated from simulations using the cosmological adaptive mesh refinement (AMR) hydro/N-body code Enzo. I will show comparisons of expected yields for various upcoming SZE cluster surveys using the Atacama Cosmology Telescope, the South Pole Telescope, Planck, and others as calculated from our synthetic surveys.

These synthetic surveys provide extremely useful guidance for the interpretation of galaxy cluster surveys. The precise
quantification of survey systematics will allow observers to both create effective survey strategies and ultimately to accurately determine cosmological parameters.

RS Oph was observed in outburst on February 12, 2006 and, for at least the fifth time in recorded history, reached naked eye visibility. RS Oph is a member of a class of stars called recurrent novae because their outbursts have been detected more than once. We jumped at the opportunity to observe this system both with the large number of satellites now in orbit and ground based facilities that had far superior detectors to those available for its last outburst in January 1985. This system has a white dwarf (probably massive) in a 455 day orbit around a cool giant. The giant is transferring hydrogen rich matter onto the white dwarf at a rate that is sufficient for an explosion every 20 years or so. In contrast, a classical nova binary system also contains a white dwarf star but the mass losing star is a low mass star (like the sun) in a few hour orbit around the white dwarf and the time between explosions may be as long as 100,000 years or more. I will report on the unprecedented data that we obtained with X-ray satellites such as Chandra and Swift plus discuss the possible relationship between RS Oph and Supernovae of Type Ia. These latter explosions are thought responsible for the iron group elements in the Solar System and are now being used to study the evolution of the Universe.

The capabilities of the 6.5 meter James Webb Space Telescope (JWST) --- slated for launch to a halo L2 orbit in 2013 --- are reviewed, including the considerations to make this an optimized infrared telescope that can deploy automatically in space. The main science themes of this telescope are to measure First Light, Reionization, Galaxy Assembly, as well as the process of Star-formation and the origin of Planetary Systems. The talk will outline how the JWST will go about measuring First Light, Reionization, and Galaxy Assembly, building on lessons learned from the Hubble Space Telescope. In detail, JWST will map the epoch of First light through Pop III star clusters at redshifts z=8--20, and its transition to the first Pop II stars in dwarf galaxies that likely finished cosmic reionization at redshifts z=6-7. I will show what deep JWST images may look like compared to the Hubble UltraDeep Field, and what nearby galaxies observed in their restframe UV--optical light would look like to JWST at very high redshifts. I'll demonstrate an interactive web-tool that lets the user zoom 3-D into the Hubble UltraDeep Field --- and beyond into the epoch of First Light --- with all galaxy
images sorted versus redshift. Time permitting, I will discuss issues of the natural confusion limit as they may apply to JWST, and algorithms that may be needed to automatically detect objects in crowded ultradeep JWST fields.

Comet nuclei coalesced from the refractories and ices present in the outer-planets region of the proto-solar system. The interiors of comets have remained at low temperatures in the Kuiper Belt or Oort Cloud that over the past 4.5 Gyr of solar system history. Thus, comets are time capsules -- records of the thermal, chemical, and dynamical environment of the protoplanetary disk. However, comets are not wholly pristine and before we can definitively link their dust and ice properties to the conditions of the early solar system, we must understand their ensemble histories. To that end, we compare the physical properties of comet nuclei to related planetesimals to probe the evolution of small bodies in the solar system. Jupiter-family comets are well-suited to the study of comet surfaces because their nuclei are more accessible than those of the long-period comets. We have an optical/mid-infrared survey of 100 Jupiter-family comets (nearly one-third of all known JFCs) designed to measure their sizes and albedos. We use our completed mid-infrared survey to derive a new and independent estimate of the current Jupiter-family comet size distribution. The optical component of the survey is in progress. The albedo and size distributions are important characteristics in comparisons of comets to their dynamically related bodies: Trojans, Centaurs, and transneptunian objects.

Classical Novae are thermonuclear explosions that occur in stellar binary systems consisting of a solar-like star and a so-called White Dwarf, an old stellar object that has shrunk to a degree of compactness that it consists only of degenerate matter after having lost all of its hydrogen. Mass transfer from the solar-like star to the White Dwarf provides new hydrogen-rich material that will ignite a nuclear fusion reaction chain. While this principle is always the same, all Classical Novae observed so far have been quite different in their evolution. X-ray observations reveal central pieces of information as they allow insights into the hottest processes. I will give a description of the typical evolution of Classical Novae and show examples of X-ray spectra during the different phases of evolution. A more detailed view also illustrates how different the evolution can be when different system parameters are given.

As part of a program to search for and characterize the presence of warm dust in the habitable zones around nearby solar like stars, we have search for dust within a few AU of the central stars. We have observed 152 FGKM stars with the Spitzer short-low and long-low IRS modules, and using the FLUOR instrument on the CHARA interferometer, we have observed the main sequence A stars beta Leo and zeta Lep, which are known to have a debris disk. I will present an overview of our results.

As the nearest actively star-forming galaxies, the Magellanic Clouds offer a unique opportunity to study the physical processes that drive galaxy evolution. Years of effort have produced great strides in our understanding of these galaxies, and with comprehensive surveys of the Clouds in both optical and infrared bands coming online, it is truly an exciting time to be a Magellanic researcher. However, the Clouds don't give up their secrets easily, and many fundamental aspects of their nature remain shrouded in mystery. I will present some of these mysteries, and the present and future lines of research which will lead to their resolution.

I will provide an overview on progress and problems in understanding the structure of the Milky Way, with a focus on recent results on the stellar structure of the Galaxy using the Spitzer Space Telescope. This will include the most recent estimates on the distance to the center of the Galaxy (shorter than you might have thought), the parameters of the stellar bar(s) of the Galaxy (more complicated than you might have assumed), the number of stellar spiral arms of the Galaxy (fewer than you may have heard). I will also present recent work on the vertical scaleheight (and radial dependence) of the different components of the stellar Galaxy. The relation between the mass density of the Galaxy, traced by the mid-infrared light, and the galactic scale star formation will also be discussed.

White Dwarf (WD) stars are the most common stellar remnant, being produced by all stars below about 8 times the mass of our sun. Put in a close binary, a WD can gain mass from a companion and undergo a variety of bright, dynamic outburst phenomenon driven by both accretion and thermonuclear explosion. I will discuss how we study the WDs in these systems, during both outburst and quiescence, and what we are learning about their population as a whole and how these binaries form and evolve. I will highlight the ignition of the brightest outbursts they make: Classical Novae -- due to thermonuclear runaway in hydrogen-rich material on the WD surface -- and Supernovae -- due to carbon-burning thermonuclear runaway in the deep interior. Particular attention will be paid to how the features of the evolution of the binary might determine aspects of the explosions. These systems are thought to produce the Supernovae of Type Ia, which have remarkably regular characteristics and are therefore of great interest as standard candles for cosmology. Interesting puzzles remain in our theoretical understanding of these systems and their remarkable outbursts.

Despite intense scrutiny, the progenitor system(s) that gives rise to Type Ia supernovae has remained remarkably unconstrained by direct observation. The favored theory invokes a carbon-oxygen white dwarf accreting hydrogen-rich material from a close companion until a thermonuclear runaway ensues that incinerates the white dwarf. However, simulations resulting from this single-degenerate, binary channel demand the presence of low-velocity H-alpha emission in spectra taken during the late nebular phase, since a portion of the companion's envelope becomes entrained in the ejecta. This hydrogen has never been detected, but has only rarely been sought. In this talk I will present results from an ongoing campaign to obtain deep, multi-epoch, nebular-phase spectroscopy of nearby Type Ia supernovae in an effort to detect this telltale signature of the companion star. Results from two additional investigations that each seek different observational signatures resulting from popular progenitor system models will also be discussed.

The advent of powerful ground- and space-based telescopes and extremely sensitive detectors has enabled the development of a comprehensive picture of the formation and evolution of planetary systems, enabling us to better place our solar system in a broad astrophysical context. In this presentation, I will briefly summarize our current understanding of these processes and their intimate connection with stellar evolution. I will
highlight this overview with many new results from the Hubble and Spitzer Space Telescopes that capture the formation and evolutionary processes in action.

We explore the relationship of the hosts of luminous quasars to normal giant elliptical galaxies in order to look for evidence of evolutionary trends. We use measured stellar velocity dispersions combined with effective radii and magnitudes from the literature to place the host galaxies of 8 luminous quasars (MV < -23) on the Fundamental Plane (FP), where their properties are compared to other types of galaxies. We find that the radio-loud (RL) QSO hosts have similar properties to massive elliptical galaxies, while the radio-quiet (RQ) hosts are more similar to intermediate mass galaxies. The RL hosts lie at the upper extreme of the FP due to their large velocity dispersions , low surface brightness , and large effective radii and M/L = 14.1. Our data support previous results that PG QSOs are related to gas-rich galaxy mergers that form intermediate-mass galaxies, while RL QSOs reside in massive early-type galaxies, some of which also show signs of recent mergers. Most previous work has drawn these conclusions by using estimates of the black hole mass and inferring host galaxy properties from that, while here we have relied purely on directly measured host galaxy properties.

In the past five years several trends have synergistically enhanced the importance of the most massive stars for astrophysics and cosmology. The GRB and first-stars connections remain valid, but now we also have the recognition of a class of Supernova Impostors, a revolution in our understanding of the Eddington Limit, recent theoretical models of ultra-high-energy supernovae, and other unexpected developments. Collectively, stars above 100 Msun have become essential both for cosmology and for astrophysical processes in general. A large fraction of everything known about such objects is based on Eta Carinae, which is far easier to observe than any other object in the class. Eta's bizarre phenomena have repeatedly exposed gaps and errors in existing theory. Observations of this object have undergone another revolution in the past decade, while, independently, it shows signs of changing to a different physical state. Here I shall review the current significance of the most massive stars, of supernova impostors, and recent surprises concerning Eta Carinae.

A key longstanding problem in space and astrophysical plasmas is determining the mechanism that accelerates electrons to relativistic energies. It is critical to understanding the dynamics of the Van Allen radiation belts, where MeV electrons can damage spacecraft systems. We report the discovery, in STEREO S/WAVES data, of obliquely-propagating whistler-mode waves in the radiation belt with electric field amplitudes more than an order of magnitude larger than other whistlers. Simulations show that these large amplitude waves can energize an electron by an MeV in less than 0.1s, explaining the rapid enhancement in electron intensities observed between the STEREO-A and STEREO-B passages through the belt. Our results show that the usual theoretical models of electron energization and scattering via small-amplitude waves, with timescales of hours to days, are inadequate for understanding radiation belt dynamics.