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We’ve come a long way since 1609, from spectacle lenses to mirrors in space, from twitching frog legs to the Event Horizon Telescope observing a black hole. But far more is possible. On the ground, a new generation of optical telescopes is under construction, up to 39 m in diameter. Adaptive optics compensates for the turbulent atmosphere, but could work far better with an orbiting reference beacon in space. Bright chemiluminescent emission lines in the upper atmosphere interfere with observations, but could be blocked by fiber optic filters. Energy-resolving photon counting detectors promise far greater sensitivity. New ways of making mirrors offer far better resolution for space X-ray telescopes. Coronagraphs can suppress starlight enough to reveal exoplanets in direct imaging, or starshades can cast star shadows on telescopes to do the same thing. New generations of far IR detectors with large cryogenic telescopes in space can reveal the cool and cold universe. Radio telescopes on the quiet far side of the Moon can overcome the limits of the ionosphere and intense local interference to see events in the early universe as it heated up again after the Big Bang expansion cooled everything. Neutrino telescopes can see stars being shredded by black holes, and gravitational wave detectors see merging neutron stars and black holes. Atom wave gravimeters can measure the internal structure of planets and asteroids, and sample return missions are already bring back distant bits of the solar system. What will happen next? I don’t know but it will be glorious.

Delabrouille, J., et al., This paper discusses the science case for a sensitive spectro-polarimetric survey of the microwave sky. Such a survey would provide a tomographic and dynamic census of the three-dimensional distribution of hot gas, velocity flows, early metals, dust, and mass distribution in the entire Hubble volume, exploit CMB temperature and polarisation anisotropies down to fundamental limits, and track energy injection and absorption into the radiation background across cosmic times by measuring spectral distortions of the CMB blackbody emission. In addition to its exceptional capability for cosmology and fundamental physics, such a survey would provide an unprecedented view of microwave emissions at sub-arcminute to few-arcminute angular resolution in hundreds of frequency channels, a data set that would be of immense legacy value for many branches of astrophysics. We propose that this survey be carried out with a large space mission featuring a broad-band polarised imager and a moderate resolution spectro-imager at the focus of a 3.5 m aperture telescope actively cooled to about 8K, complemented with absolutely-calibrated Fourier Transform Spectrometer modules observing at degree-scale angular resolution in the 10–2000 GHz frequency range. We propose two observing modes: a survey mode to map the entire sky as well as a few selected wide fields, and an observatory mode for deeper observations of regions of specific interest., This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 725456, CMBSPEC) as well as the Royal Society (grants UF130435 and RG140523). JARM acknowledges financial support from the Spanish Ministry of Science and Innovation (MICINN) under the project AYA2017-84185-P, and from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement 687312 (RADIOFOREGROUNDS). C.H.-M. acknowledges the support of the Spanish Ministry of Science through project PGC2018-097585-B-C21. Financial support from the ASI/Physics Department of the University of Roma–Tor Vergata agreement n. 2016-24-H.0 for study activities of the Italian cosmology community is acknowledged. JLB is supported by the Allan C. and Dorothy H. Davis Fellowship, and has been supported by the Spanish MINECO under grant BES-2015-071307, co-funded by the ESF during part of the development of this work.

The Origins Space Telescope will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did galaxies evolve from the earliest galactic systems to those found in the universe today? How do habitable planets form? How common are life-bearing worlds? To answer these alluring questions, Origins will operate at mid- and far-infrared wavelengths and offer powerful spectroscopic instruments and sensitivity three orders of magnitude better than that of Herschel, the largest telescope flown in space to date. After a 3 ½ year study, the Origins Science and Technology Definition Team will recommend to the Decadal Survey a concept for Origins with a 5.9-m diameter telescope cryocooled to 4.5 K and equipped with three scientific instruments. A mid-infrared instrument (MISC-T) will measure the spectra of transiting exoplanets in the 2.8 – 20 μm wavelength range and offer unprecedented sensitivity, enabling definitive biosignature detections. The Far-IR Imager Polarimeter (FIP) will be able to survey thousands of square degrees with broadband imaging at 50 and 250 μm. The Origins Survey Spectrometer (OSS) will cover wavelengths from 25 – 588 μm, make wide-area and deep spectroscopic surveys with spectral resolving power R ~ 300, and pointed observations at R ~ 40,000 and 300,000 with selectable instrument modes. Origins was designed to minimize complexity. The telescope has a Spitzer-like architecture and requires very few deployments after launch. The cryo-thermal system design leverages JWST technology and experience. A combination of current-state-of-the-art cryocoolers and next-generation detector technology will enable Origins’ natural backgroundlimited sensitivity.

The mysterious acceleration of the expansion of the Universe, discovered in 1998, can be described by the cosmological constant introduced by Einstein in 1917. In the quantum cosmology, the existence of a repulsive force is associated with "dark energy" - a hypothetical substance with a negative pressure. But numerous attempts to obtain from the quantum theory the observed value of the cosmological constant lead to values of 120 orders of magnitude larger than the observed value. In the bouncing cosmology, a collapse of the Universe of the previous cycle is supposed, and then its new divergence. We consider the bouncing cosmology in the light of the latest discovery of gravitational waves and a large number of massive black holes, which are a probable candidate for the role of dark matter. When the Universe collapses, a significant part of the gravitational mass of the merging black holes turns into gravitational waves. During mergers, the size of black holes increases. We call the largest of them the Big Black Hole (BBH). In the stage of expansion, the frequency of mergers of black holes will decrease sharply and the reverse process will begin due to the absorption of gravitational waves: the slow growth of the mass of black holes, first of all the BBH, which has the maximum surface. If we assume that gravitational radiation themselves do not generate a gravitational field, then it can be shown that a sharp decrease in the gravitational mass of the Universe causes strong antigravity, which can be responsible for the Big Bang. The gravitational mass of BBH at the stage of expansion of the Universe will grow and the gravitational influence of BBH will stretch a field of galaxies. This stretching effect is described by the appearance of a cosmological constant in the Friedmann equations. An estimated value of the cosmological constant is in good agreement with the observations. A cyclic model of the Universe can be developed on the basis of periodic transformation of the mass of merging black holes into gravitational waves and absorption of the background gravitational radiation by the BBH.

Planned for launch in 2019 on an Ariane 5 from French Guiana, JWST will observe at wavelengths from 0.6 to 28 µm with a full suite of imagers, spectrometers, and coronagraphs. JWST will extend the discoveries of the Hubble and Spitzer observatories in all areas from cosmology, galaxies, stars, and exoplanets to our own Solar System. With a 6.5 m primary mirror it has a collecting area 7 times that of Hubble and 50 times that of Spitzer. The image quality is diffraction limited at 2 µm with near IR camera pixels of only 0.03 arcsec. I will outline the planned observing program, showing how the instrument capabilities enable new discoveries in new territories. What were the first objects that formed in the expanding universe? How do the galaxies grow? How are black holes made, ranging from stellar mass to supermassive, over a billion solar masses, and what is their effect on the neighborhood? How are stars and planetary system formed? What governs the evolution of planetary systems, with the possibility of life? How did the Earth become so special? But the most important discoveries will be those we have not even imagined today.

The Space High Angular Resolution Probe for the Infrared (SHARP-IR) is a new mission currently under study. As part of the preparation for the Decadal Survey, NASA is currently undertaking studies of four major missions, but interest has also been shown in determining if there are feasible sub-$1B missions that could provide significant scientific return. SHARP-IR is being designed as one such potential probe. In this talk, we will discuss some of the potential scientific questions that could be addressed with the mission, the current design, and the path forward to concept maturation.

This paper provides a detailed description of the data reduction and analysis procedures that have been employed in our previous studies of spatial fluctuation of the cosmic infrared background (CIB) using deep Spitzer IRAC observations. The self-calibration we apply removes a strong instrumental signal from the fluctuations which would otherwise corrupt our results. The procedures and results for masking bright sources, and modeling faint sources down to levels set by the instrumental noise are presented. Various tests are performed to demonstrate that the resulting power spectra of these fields are not dominated by instrumental or procedural effects. These tests indicate that the large scale (>~30') fluctuations that remain in the deepest fields are not directly related to the galaxies that are bright enough to be individually detected. We provide the parameterization of these power spectra in terms of separate instrument noise, shot noise, and power law components. Our measurements of spatial fluctuations of the CIB intensity indicate the mean emission from the objects producing the fluctuations is quite low (>~1 nW m-2 sr-1 at 3-5 micron), and thus consistent with current gamma-ray absorption constraints. The source of the fluctuations may be high-z Population III objects, or a more local component of very low luminosity objects with clustering properties that differ from the resolved galaxies. Finally, we discuss the prospects of the upcoming space-based surveys to directly measure the epochs inhabited by the populations producing these source-subtracted CIB fluctuations, and to isolate the individual fluxes of these populations.

The simulated Doppler shifts of the solar Mg I Fraunhofer line produced by scattering on the solar light by asteroidal, cometary, and trans-neptunian dust particles are compared with the shifts obtained by Wisconsin H-Alpha Mapper (WHAM) spectrometer. The simulated spectra are based on the results of integrations of the orbital evolution of particles under the gravitational influence of planets, the Poynting–Robertson drag, radiation pressure, and solar wind drag. Our results demonstrate that the differences in the line centroid position in the solar elongation and in the line width averaged over the elongations for different sizes of particles are usually less than those for different sources of dust. The deviation of the derived spectral parameters for various sources of dust used in the model reached maximum at the elongation (measured eastward from the Sun) between 90° and 120°. For the future zodiacal light Doppler shifts measurements, it is important to pay a particular attention to observing at this elongation range. At the elongations of the fields observed by WHAM, the model-predicted Doppler shifts were close to each other for several scattering functions considered. Therefore the main conclusions of our paper do not depend on a scattering function and mass distribution of particles if they are reasonable. A comparison of the dependencies of the Doppler shifts on solar elongation and the mean width of the Mg I line modeled for different sources of dust with those obtained from the WHAM observations shows that the fraction of cometary particles in zodiacal dust is significant and can be dominant. Cometary particles originating inside Jupiter's orbit and particles originating beyond Jupiter's orbit (including trans-neptunian dust particles) can contribute to zodiacal dust about 1/3 each, with a possible deviation from 1/3 up to 0.1–0.2. The fraction of asteroidal dust is estimated to be ∼0.3–0.5. The mean eccentricities of zodiacal particles located at 1–2 AU from the Sun that better fit the WHAM observations are between 0.2 and 0.5, with a more probable value of about 0.3.

NASA's Cosmic Background Explorer satellite mission, the COBE, laid the foundations for modern cosmology by measuring the spectrum and anisotropy of the cosmic microwave background radiation and discovering the cosmic infrared background radiation. I describe the history of the COBE project, its scientific context, the people who built it, and the scientific results. The COBE observed the universe on the largest scales possible by mapping the cosmic microwave and infrared background radiation fields and determining their spectra. It produced conclusive evidence that the hot Big Bang theory of the early universe is correct, showed that the early universe was very uniform but not perfectly so, and that the total luminosity of post--Big Bang objects is twice as great as previously believed. The COBE concept was developed by a Mission Definition Study Team appointed by NASA in 1976, based on three competing proposals submitted in 1974. The COBE was built in-house by Goddard Space Flight Center, with a helium cryostat provided by Ball Aerospace, and was launched on a Delta rocket built by McDonnell Douglas. It is in a circular orbit $900\phantom{\rule{0.3em}{0ex}}\mathrm{km}$ above the Earth, in a plane inclined 99\ifmmode^\circ\else\textdegree\fi{} to the equator and roughly perpendicular to the line to the Sun. It carried three instruments, a far infrared absolute spectrophotometer (FIRAS), a differential microwave radiometer with three channels (DMR), and a diffuse infrared background experiment (DIRBE). The helium cryostat cooled the FIRAS and DIRBE for $10\phantom{\rule{0.3em}{0ex}}\text{months}$ until the helium was exhausted, but operations continued for a total of $4\phantom{\rule{0.3em}{0ex}}\text{years}$. Subsequent observations have confirmed the COBE results and led to measurements of the main cosmological parameters with a precision of a few percent.

We study the possible contribution of optical galaxies detected with the Hubble ACS instrument to the near-IR cosmic infrared (CIB) fluctuations in deep Spitzer images. The Spitzer data used in this analysis are obtained in the course of the GOODS project, from which we select four independent 10' × 10' regions observed at both 3.6 and 4.5 μm. ACS source catalogs for all of these areas are used to construct maps containing only their emissions in the ACS B,V,i,z bands. We find that deep Spitzer data exhibit CIB fluctuations remaining after removal of foreground galaxies of a very different clustering pattern at both 3.6 and 4.5 μm than the ACS galaxies could contribute. We also find that there are very good correlations between the ACS galaxies and the removed galaxies in the Spitzer maps, but practically no correlations remain with the residual Spitzer maps used to identify the CIB fluctuations. These contributions become negligible on larger scales used to probe the CIB fluctuations arising from clustering. This means that the ACS galaxies cannot contribute to the large-scale CIB fluctuations found in the residual Spitzer data. The absence of their contributions also means that the CIB fluctuations arise at z 6.5 as the Lyman break of their sources must be redshifted past the longest ACS band, or the fluctuations have to originate in the more local but extremely low luminosity galaxies.

We integrated the orbital evolution of 30,000 Jupiter-family comets, 1300 resonant asteroids, and 7000 asteroidal, trans-Neptunian, and cometary dust particles. For initial orbital elements of bodies close to those of Comets 2P, 10P, 44P, and 113P, a few objects got Earth-crossing orbits with semi-major axes $a$$, Comment: Submitted to Proc. of the IAU Colloquium N 197 "Dynamics of populations of planetary systems" (Belgrade, Serbia and Montenegro, 31 August - 4 September, 2004)

Our efficient numerical approach has been applied to modeling the asymmetric circumstellar dust disk around β Pictoris as observed with the HST/STIS. We present a new model on the origin of the warping of the β Pic disk. We suggest that the observed warp is formed by the gravitational influence of a planet with a mass of about 10 masses of Earth, at a distance of 70 AU, and a small inclination (∽ 2.5°) of the planetary orbit to the main dust disk. Results of our modeling are compared with the STIS observations.

This is one of two papers in which we report the detection of structure in the cosmic infrared background (CIB) between 1.25 - 2.2 micron through the use of data from the Two Micron Sky Survey (2MASS). This paper concentrates on data assembly, analysis and the estimate of the various foreground contributions; the companion paper (Kashlinsky, Odenwald, Mather, Skrutskie, Cutri 2002, hereafter KOMSC) presents the cosmological results for the CIB fluctuations and their implications. By using repeated observations of a specific calibration star field, we were able to achieve integration times in excess of 3900 seconds compared to the 7.8 seconds in the standard 2MASS data product. This yielded a point source detection limit (3 \sigma) of +18.5^m in K_s band. The resulting co-added images were processed to remove point sources to a limiting surface brightness of +20^m/arcsec$^2 or 40 nW/m^2/sr. The remaining maps contained over 90% of the pixels and were Fourier transformed to study the spatial structure of the diffuse background light. After removing resolved sources and other artifacts, we find that the power spectrum of the final images has a power-law distribution consistent with clustering by distant galaxies. We estimate here the contributions to this signal from Galactic foregrounds, atmospheric OH-glow, zodiacal light and instrument noise, all of which are small and of different slopes. Hence, this supports the KOMSC identification of the signal as coming from the CIB fluctuations produced by distant clustered galaxies.

In the spirit of the Lindau Meeting, we present a dialogue between a Nobel laureate and a young researcher. This interchange started online, where it continues to unfold. Here is a digest of this conversation, which has developed across time and space.

The cosmic microwave background (CMB) spectral results of the Far-Infrared Absolute Spectrophotometer (FIRAS) instrument are summarized. Some questions that have been raised about the calibration accuracy are also addressed. Finally, we comment on the potential for major improvements with new measurement approaches. The measurement of the deviation of the CMB spectrum from a 2.725 ± 0.001 K blackbody form made by the COBE-FIRAS could be improved by nearly 2 orders of magnitude.

We report first results for the cosmic infrared background (CIB) fluctuations at 1.25, 1.65 and 2.17 micron obtained from long exposures constructed from 2MASS standard star fields. We have co-added and analyzed scans from one such field with a total exposure time > 1 hour, and removed sources and other artifacts. The stars and galaxies were clipped out to K_s~19^m leaving only high-z galaxies (or possibly local low-surface-brightness systems). The residual component of the diffuse emission on scales from a few arc-sec to a few arc-min has a power-law slope consistent with emission produced by clustered galaxies. The noise (and residual artifacts) contribution to the signal is small and the colors of the signal are very different from Galactic stars or air-glow. We therefore identify the signal as CIB fluctuations from the faint unresolved galaxies. We show that the present-day galaxies with no evolution would produce a significant deficit in the observed CIB fluctuations. Thus the dominant contribution to the observed signal must come from high z and may indicate high rates of star formation at those epochs., Ap. J. Letters, in press

We present new methodology to use cosmic infrared background (CIB) fluctuations to probe sources at 1030., Comment: ApJ, in press. Minor revisions/additions to match the version in proofs

We examine cosmic ray rejection methodology on data collected from InSb and Si:As detectors. The application of an Up-the-Ramp sampling technique with cosmic ray identification and mitigation is the focus of this study. This technique is valuable for space-based observatories which are exposed to high-radiation environments. We validate the Up-the-Ramp approach on radiation-test data sets with InSb and Si:As detectors which were generated for SIRTF. The Up-the-Ramp sampling method studied in this paper is over 99.9% effective at removing cosmic rays and preserves the structure and photometric quality of the image to well within the measurement error.

The Next Generation Space Telescope (NGST) will be an 8 m deployable telescope, radiatively cooled to 30 K and diffraction-limited at 2 μm, operating at the Sun-Earth Lagrangian point L2. It will be built by a partnership of NASA, ESA, and CSA (Canadian Space Agency). The camera sensitivity should be limited by the zodiacal light for wavelengths < 10 μm. The main scientific objectives are the study of the origin and evolution of galaxies, stars, and planets, beginning with the first luminous objects to form from the Big Bang. Other objectives include studies of dark matter, supernovae, the intergalactic medium, gamma ray bursts, star ages, and exobiology. The telescope will be operated like the Hubble Space Telescope (HST) by the Space Telescope Science Institute, with all observing programs openly solicited and selected by peer review.The NGST scientific requirements originated with the report of the Dressler Committee HST & Beyond. The instruments recommended by the Ad Hoc Science Working Group (ASWG) include 1) a wide field near infrared (NIR) camera with an 8K2 detector array covering 0.6 - 5 μm, 2) a multi-object NIR spectrograph capable of simultaneously observing > 100 objects with a resolution of R (λ/δλ) = 1000, and 3) a combined mid-infrared (MIR) camera and spectrograph from 5-27 μm, with a resolution of R > 1500.

We present an algorithm to optimally process uniformly sampled array image data obtained with a nondestructive readout. The algorithm discards full wells, removes cosmic ray (particle) hits and other glitches, and makes a nearly optimum estimate of the signal on each pixel. The algorithm also compresses the data. The computer requirements are modest, and the results are robust. The results are shown and compared to results of Fowler sampled and processed data. Non-ideal detector performance may require some additional code, but this is not expected to cost much processing time. Known types of detector faults are addressed., This paper has been accepted for publication in the PASP

The COBE Far Infrared Absolute Spectrophotometer (FIRAS) observations constitute an unbiased survey over the wavelength range from 100 μm to 1 cm over 99% of the sky. Improved calibration of the FIRAS instrument and the inclusion of all of the FIRAS data allow an improved signal-to-noise ratio determination of the spectral lines by a factor of ~2 over our previous results. The resolution is low (0.45 cm-1), so only the strongest lines are observable. The CO chain from J = 1-0 to J = 8-7 is observed toward the Galactic center. The line ratios are roughly consistent with a 40 K excitation temperature. The 157.7 μm C II and 205.3 μm N II lines are observable over most of the sky. The 370.4 and 609.1 μm lines of C I and the 121.9 μm line of N II are observed in the Galactic plane. The line ratios at the Galactic center are consistent with a density of n0 ~ 30 cm-3 and a UV flux of G0 ≈ 15 μW m-2 sr-1 (10 Habing units). The 269 μm H2O line is observed toward the Galactic center in absorption.

In this paper we examine the cosmological constraints of the recent DIRBE and FIRAS detection of the extragalactic background light between 125-5000 microns on the metal and star formation histories of the universe., Comment: 38 pages and 9 figures. Accepted for publications in The Astrophysical Journal

The effect of solar or stellar radiation on dust particles' trajectories (the Poynting-Robertson drag) has been studied by a number of authors and applied to interplanetary dust dynamics in numerical computations. Meanwhile some important features of dust flows can be studied analytically by implementing our novel hydrodynamical approach to use the continuity equation written in the particle's orbital elements as coordinates (Gor'kavyi, Ozernoy, & Mather 1997). By employing this approach and integrating the continuity equation, we are able to find two integrals of motion when the Poynting-Robertson drag dominates the dissipative forces in the dust flow. These integrals of motion enable us to explore basic characteristics of dust flows from any sources in the Solar system (such as asteroids, comets, Kuiper belt, etc.) or in another planetary system. In particular, we have reproduced the classical solution $n(r)\propto r^{-1}$ that approximately represents the overall distribution of dust in the Solar system. We have also investigated various factors that could be responsible for the deviations of the power law index in $n(r)\propto r^{\delta}$ from $\delta=-1$, including the influences of the orbital characteristics of dust sources, the evaporation of dust particles, as well as mixtures of dust particles of both asteroidal and cometary origin. We have calculated the masses and number densities of asteroidal and cometary components of the zodiacal cloud at different distances from the Sun., Comment: Accepted for publication in ApJ, v. 488, Oct. 10, 1997; 22 pages, Latex, 12 Postscript figures

We analyze the Cosmic Microwave Background (CMB) anisotropy data from the independent COBE FIRAS and DMR observations. We extract the frequency spectrum of the FIRAS signal that has the spatial distribution seen by DMR and show that it is consistent with CMB temperature fluctuations in the radiation well into the Wien region of the spectrum. Conversely, we form a map of the Planckian component of the sky temperature from FIRAS and show that it correlates with the DMR anisotropy map. The rms fluctuations at angular scales of 7 degrees are 48 \pm 14 uK for the FIRAS data compared with 35 \pm 2 uK for the DMR data and 31 \pm 6 uK for the correlated combination (1 sigma uncertainties). The consistency of these data, from very different instruments with very different observing strategies, provide compelling support for the interpretation that the signal seen by DMR is, in fact, temperature anisotropy of cosmological origin. The data also limit rms fluctuations in the Compton y parameter, observable via the Sunyaev- Zel'dovich effect, to Delta_y < 3 x 10^{-6} (95% CL) on 7 degree angular scales.

We introduce the continuity equation written in the coordinate space of the orbital elements (e.g., semimajor axis a versus eccentricity e, etc.). This equation can serve as an effective tool to analyze the transport of interplanetary dust particles as well as their dynamical evolution, and offers a very useful complement to the approach using purely numerical integration of orbits. Using the continuity equation and suitable analytical and numerical approximations, statistically useful results can be achieved very quickly, and new integrals of the motion can be sought to simplify the description of large-scale phenomena. This paper describes the method, illustrates it with a simple example of multiple gravitational scatterings of particles on planets in circular orbits in two dimensions, and outlines the program for further development with more accurate approximations. We describe the particle dynamical evolution due to gravitational scattering by means of the "scattering matrix" W(a, e, a', e') in the continuity equation. This matrix determines both the probability of transition and the value of the particle's shift from the point a, e to the point a', e'. For purposes of illustration, two cases of the zodiacal particle diffusion due to gravitational scattering are computed, which are characterized by the initial conditions (1) (asteroid case), a0 = 2.5 AU, e0 = 0.4 (resonance 1:3 with Jupiter), and (2) (comet case), a0 = 2.22 AU, e0 = 0.846 (comet Encke). We discuss the approximations of the example and how they might be improved in future work. These include treatments of the Poynting-Robertson drag, interparticle collisions, secular perturbations, three-dimensional orbits, and resonance capture by the planets. For instance, analytical expressions are available for the rates of gradual change of orbital elements due to the Poynting-Robertson and solar wind drags, which can be incorporated easily in the "div" terms of the continuity equation.

We measure the smoothness of the infrared sky using the COBE DIRBE maps, and obtain interesting limits on the production of the diffuse cosmic infrared background (CIB) light by matter clustered like galaxies. The predicted fluctuations of the CIB with the DIRBE beam size of 07 are of the order of 10%, and the maps are smooth at the level of δνIν ~ a few nW m-2 sr-1 rms from 2.2 to 100 μm. The lowest numbers are achieved at mid- to far-IR, where the foreground is bright but smooth; they are [C(0)]1/2 ≤ (1-1.5) nW m-2 sr-1 at λ = 10-100 μm. If the CIB comes from clustered matter evolving according to typical scenarios, then the smoothness of the maps implies CIB levels less than ~(10-15) nW m-2 sr-1 over this wavelength range.

We have performed a specific observational test to measure the effect that the zodiacal light can have on measurements of the spatial fluctuations of the near-IR background. Previous estimates of possible fluctuations caused by zodiacal light have often been extrapolated from observations of the thermal emission at longer wavelengths and low angular resolution, or from IRAC observations of high latitude fields where zodiacal light is faint and not strongly varying with time. The new observations analyzed here target the COSMOS field, at low ecliptic latitude where the zodiacal light intensity varies by factors of $\sim2$ over the range of solar elongations at which the field can be observed. We find that the white noise component of the spatial power spectrum of the background is correlated with the modeled zodiacal light intensity. Roughly half of the measured white noise is correlated with the zodiacal light, but a more detailed interpretation of the white noise is hampered by systematic uncertainties that are evident in the zodiacal light model. At large angular scales ($\gtrsim100"$) where excess power above the white noise is observed, we find no correlation of the power with the modeled intensity of the zodiacal light. This test clearly indicates that the large scale power in the infrared background is not being caused by the zodiacal light., Comment: 17 pp. Accepted for publication in the ApJ

The Cosmic Background Explorer (COBE) satellite was developed by NASA's Goddard Space Flight Center to measure the diffuse IR and microwave radiation from the early universe, to the limits set by our astrophysical environment. It was launched 18 November 1989 and carried three instruments, a FIR Absolute Spectrophotometer (FIRAS) to compare the cosmic microwave background radiation with a precise blackbody, a Differential Microwave Radiometer (DMR) to map the cosmic radiation precisely, and a Diffuse Infrared Background Experiment (DIRBE) to search for the accumulated light of primeval galaxies. The cosmic microwave background radiation spectrum was measured 1000 times more precisely than was possible before the COBE launch. The microwave background was found to have an intrinsic anisotropy for the first time, at a level of a part in 10 5 with a smoothing of 10°. A comprehensive set of absolutely calibrated IR sky maps has been acquired to search for the cosmic IR background.

NASA's Cosmic Background Explorer ( COBE 1 ) carries three scientific instruments to make precise measurements of the spectrum and anisotropy of the cosmic microwave background (CMB) radiation on angular scales greater than 7° and to conduct a search for a diffuse cosmic infrared background (CIB) radiation with 0.7° angular resolution. Data from the Far-InfraRed Absolute Spectrophotometer (FIRAS) show that the spectrum of the CMB is that of a blackbody of temperature T=2.73±0.06 K, with no deviation from a blackbody spectrum greater than 0.25% of the peak brightness. The first year of data from the Differential Microwave Radiometers (DMR) show statistically significant CMB anisotropy. The anisotropy is consistent with a scale invariant primordial density fluctuation spectrum. Infrared sky brightness measurements from the Diffuse InfraRed Background Experiment (DIRBE) provide new conservative upper limits to the CIB. Extensive modeling of solar system and galactic infrared foregrounds is required for further improvement in the CIB limits.

The National Aeronautics and Space Administration (NASA) has flown the COBE satellite to observe the Big Bang and the subsequent formation of galaxies and large-scale structure. Data from the Far-Infrared Absolute Spectrophotometer (FIRAS) show that the spectrum of the cosmic microwave background is that of a black body of temperature T = 2.73 ± 0.06 K, with no deviation from a black-body spectrum greater than 0.25% of the peak brightness. The data from the Differential Microwave Radiometers (DMR) show statistically significant cosmic microwave background anisotropy, consistent with a scale-invariant primordial density fluctuation spectrum. Measurements from the Diffuse Infrared Background Experiment (DIRBE) provide new conservative upper limits to the cosmic infrared background. Extensive modeling of solar system and galactic infrared foregrounds is required for further improvement in the cosmic infrared background limits.

John Mather and George Smoot's discovery of the anisotropy of the cosmic microwave background radiation won the Nobel Prize in Physics 2006.

The James Webb Space Telescope, planned to extend the scientific discoveries of the Hubble Space Telescope, will be a powerful observational tool for the investigation of the first stars and galaxies. With a 6.5‐m hexagonal mirror cooled to ∼40 K, and an instrument package covering 0.6 to 28 μm with imaging, spectroscopy with R up to ∼3000, and coronography, it will be capable of observing predicted primeval objects down to flux levels of a few nJy (10 σ) at 2 μm. Operated like the Hubble telescope from the Space Telescope Science Institute in Baltimore, it will be available for general observers by proposals, to be solicited a year before launch. It has a required lifetime of 5 years and fuel for 10.

The James Webb Space Telescope (JWST) is a large (6.6 m), cold (

The concept and operation of the Differential Microwave Radiometers (DMR) instrument aboard NASA's Cosmic Background Explorer satellite are reviewed, with emphasis on the software identification and subtraction of potential systematic effects. Preliminary results obtained from the first six months of DMR data are presented, and implications for cosmology are discussed.

The Cosmic Background Explorer, launched November 18, 1989, has nearly completed its first full mapping of the sky with all three of its instruments: a Far Infrared Absolute Spectrophotometer (FIRAS) covering 0.1 to 10 mm, a set of Differential Microwave Radiometers (DMR) operating at 3.3, 5.7, and 9.6 mm, and a Diffuse Infrared Background Experiment (DIRBE) spanning 1 to 300 µm in ten bands. A preliminary map of the sky derived from DIRBE data is presented. Initial cosmological implications include: a limit on the Comptonization y parameter of 10−3, on the chemical potential μ parameter of 10−2, a strong limit on the existence of a hot smooth intergalactic medium, and a confirmation that the dipole anisotropy has the spectrum expected from a Doppler shift of a blackbody. There are no significant anisotropies in the microwave sky detected, other than from our own galaxy and a cosθ dipole anisotropy whose amplitude and direction agree with previous data. At shorter wavelengths, the sky spectrum and anisotropies are dominated by emission from ‘local’ sources of emission within our Galaxy and Solar System. Preliminary comparison of IRAS and DIRBE sky brightnesses toward the ecliptic poles shows the IRAS values to be significantly higher than found by DIRBE at 100 μm. We suggest the presence of gain and zero-point errors in the IRAS total brightness data. The spacecraft, instrument designs, and data reduction methods are described.

We report results of a recently-completed pre-Formulation Phase study of SPIRIT, a candidate NASA Origins Probe mission. SPIRIT is a spatial and spectral interferometer with an operating wavelength range 25 - 400 microns. SPIRIT will provide sub-arcsecond resolution images and spectra with resolution R = 3000 in a 1 arcmin field of view to accomplish three primary scientific objectives: (1) Learn how planetary systems form from protostellar disks, and how they acquire their inhomogeneous composition; (2) characterize the family of extrasolar planetary systems by imaging the structure in debris disks to understand how and where planets of different types form; and (3) learn how high-redshift galaxies formed and merged to form the present-day population of galaxies. Observations with SPIRIT will be complementary to those of the James Webb Space Telescope and the ground-based Atacama Large Millimeter Array. All three observatories could be operational contemporaneously., 20 pages, 12 figures, accepted for publication in J. Adv. Space Res. on 26 May 2007

We discuss interpretation of the cosmic infrared background (CIB) anisotropies detected by us recently in the Spitzer IRAC based measurements. The fluctuations are approximately isotropic on the sky consistent with their cosmological origin. They remain after removal of fairly faint intervening sources and must arise from a population which has a strong CIB clustering component with only a small shot-noise level. We discuss the constraints the data place on the luminosities, epochs and mass-to-light ratios of the indvidual sources producing them. Assuming the concordance LambdaCDM cosmology the measurements imply that the luminous sources producing them lie at cosmic times < 1 Gyr and were individually much brighter per unit mass than the present stellar populations., Ap.J.Letters, in press

Cosmic infrared background fluctuations may contain measurable contribution from objects inaccessible to current telescopic studies, such as the first stars and other luminous objects in the first Gyr of the Universe's evolution. In an attempt to uncover this contribution we have analyzed the GOODS data obtained with the Spitzer IRAC instrument, which are deeper and cover larger scales than the Spitzer data we have previously analyzed. Here we report these new measurements of the cosmic infrared background (CIB) fluctuations remaining after removing cosmic sources to fainter levels than before. The remaining anisotropies on scales > 0.5 arcmin have a significant clustering component with a low shot-noise contribution. We show that these fluctuations cannot be accounted for by instrumental effects, nor by the Solar system and Galactic foreground emissions and must arise from extragalactic sources., Ap.J.Letters, in press

We studied the orbital evolution of Jupiter-family comets (JFCs), Halley-type comets (HTCs), and long-period comets, and probabilities of their collisions with planets. In our runs the probability of a collision of one object with the Earth could be greater than the sum of probabilities for thousands of other objects. Even without a contribution of such a few bodies, the probability of a collision of a former JFC with the Earth was greater than 4$\cdot10^{-6}$. This probability is enough for delivery of all the water to Earth's oceans during formation of the giant planets. The ratios of probabilities of collisions of JFCs and HTCs with Venus and Mars to the mass of a planet usually were not smaller than that for Earth. Among 30,000 considered objects with initial orbits close to those of JFCs, a few objects got Earth-crossing orbits with semi-major axes $a$$, Comment: 10 pages. Paper submitted to Proc. of the IAU Symposium No. 236 "Near Earth Objects, Our Celestial Neighbors: Opportunity and Risk" (Prague, Czech Republic, August 14-18, 2006), edited by A. Milani, G.B. Valsecchi and D. Vokrouhlicky

Dark energy appears to be the dominant component of the physical Universe, yet there is no persuasive theoretical explanation for its existence or magnitude. The acceleration of the Universe is, along with dark matter, the observed phenomenon that most directly demonstrates that our theories of fundamental particles and gravity are either incorrect or incomplete. Most experts believe that nothing short of a revolution in our understanding of fundamental physics will be required to achieve a full understanding of the cosmic acceleration. For these reasons, the nature of dark energy ranks among the very most compelling of all outstanding problems in physical science. These circumstances demand an ambitious observational program to determine the dark energy properties as well as possible.

We report results of a recently-completed pre-Formulation Phase study of SPIRIT, a candidate NASA Origins Probe mission. SPIRIT is a spatial and spectral interferometer with an operating wavelength range 25 - 400 μm. SPIRIT will provide sub-arcsecond resolution images and spectra with resolution R = 3000 in a 1 arcmin field of view to accomplish three primary scientific objectives: (1) Learn how planetary systems form from protostellar disks, and how they acquire their chemical organization; (2) Characterize the family of extrasolar planetary systems by imaging the structure in debris disks to understand how and where planets form, and why some planets are ice giants and others are rocky; and (3) Learn how high-redshift galaxies formed and merged to form the present-day population of galaxies. Observations with SPIRIT will be complementary to those of the James Webb Space Telescope and the ground-based Atacama Large Millimeter Array. All three observatories could be operational contemporaneously.

The proposed design includes 3 new ideas to increase the signal-noise ratio of instruments for the detection and study of extra-solar planets in space and on the ground. The instrument is to be added to systems that cancel the stellar halo, for example coronagraphs with adaptive speckle cancellation using integral field low resolution spectroscopy for speckle detection. The new design then gives an additional sensitivity to other hallo cancellation methods by hardware and/or software. The first part of the instrument spectrally splits the image into 50 to 100 narrowband images with independent optimal bandwidths and central wavelengths. This permits to have for example a uniform spectral resolution by making each bandwidth proportional to the wavelength or to adjust some bandwidths and central wavelengths to specifically target important lines. It also gives in each narrowband image optimum independent spatial sampling, for example 2 pixel per diffraction limit. This cannot be done with field sampling integral field systems as image slicers and TIGER type lens arrays. Another advantage is that there is very little contamination between spectral pixels as opposed to a slit spectrograph where the slit has a significant width compared to the pixel size, being in fact usually larger. Consequently, if a TIGER type lens array is added at the input, all 3 dimensions of the 3-D data box have very little contamination. In the second part of the instrument, the darker regions around the speckles of the narrowband images are reflected back into the spectrograph to reconstruct a white light image with a far higher contrast than at the input. The total additional gain should be equivalent to at least an order of magnitude increase in throughput. Finally, instead of reconstructing one white light image, a small number of images each with its own carefully chosen bandwidth and central wavelength can be reconstructed for specific programs as detection of life. Groups of bandwidths can also be reconstructed into white light in individual images. The system can be used as much in space than on the ground.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The deepest space- and ground-based observations find metal-enriched galaxies at cosmic times when the Universe was less than 1 Gyr old. These stellar populations had to be preceded by the metal-free first stars, known as 'population III'. Recent cosmic microwave background polarization measurements indicate that stars started forming early--when the Universe wasor =200 Myr old. It is now thought that population III stars were significantly more massive than the present metal-rich stellar populations. Although such sources will not be individually detectable by existing or planned telescopes, they would have produced significant cosmic infrared background radiation in the near-infrared, whose fluctuations reflect the conditions in the primordial density field. Here we report a measurement of diffuse flux fluctuations after removing foreground stars and galaxies. The anisotropies exceed the instrument noise and the more local foregrounds; they can be attributed to emission from population III stars, at an era dominated by these objects.

The Single Aperture Far-InfraRed (SAFIR) Observatory's science goals are driven by the fact that the earliest stages of almost all phenomena in the universe are shrouded in absorption by and emission from cool dust and gas that emits strongly in the far-infrared and submillimeter. Over the past several years, there has been an increasing recognition of the critical importance of this spectral region to addressing fundamental astrophysical problems, ranging from cosmological questions to understanding how our own Solar System came into being. The development of large, far-infrared telescopes in space has become more feasible with the combination of developments for the James Webb Space Telescope and of enabling breakthroughs in detector technology. We have developed a preliminary but comprehensive mission concept for SAFIR, as a 10 m-class far-infrared and submillimeter observatory that would begin development later in this decade to meet the needs outlined above. Its operating temperature (, 36 pages

著者人数：34名, 資料番号: SA1001798000