Report on Mini-conference on Sludge Disposal Alternatives in the Ocean off Southern California, 8 September 1976

The purpose of the conference was to review the status of our capability to predict the environmental effects of the disposal of digested sewage sludge in the ocean off the coast of Southern California. At present, the ocean disposal of sewage sludge is prohibited by State and Federal regulations. Ocean disposal of sludge, however, is a complex of many alternative combinations of what, where and how; and the environmental consequences of all such combinations have not yet been determined. There is, in fact, some evidence that at least one environmentally sound mode of sludge disposal in the ocean off the Southern California coast may exist. This is the trapping of sludge in the sediments of deep, nearshore ocean basins. such as the Santa Monica Basin. Details of this method are given in Section 3.3. p. 12. It is the philosophy of the Environmental Quality Laboratory to study and evaluate policy alternatives but not to be an advocate of one alternative or another. Some of the policies studied may be contrary to existing laws or regulations, but it is believed that there is a better chance for improvement in the laws or regulations if alternatives currently outside them are also studied. The conference was sponsored by the Environmental Quality Laboratory in the belief that sufficient information is now available to begin making reasonable estimates of the environmental consequences of existing or alternative ocean disposal methods in order to compare them to land-based disposal methods. The purpose of this report is not to publish the actual proceedings of the conference. but rather to act as a communications aid. It is intended to publicize the issues that were raised at the conference, to give the names and addresses of people who are involved in these issues, and to present abstracts and literature citations. The schedule of the conference is presented in the next section. It is followed by a section containing abstracts of current research by conference attendees along with reference lists supplied by them. The fourth section is a summary of the afternoon discussion sessions. The final section is a list of conference attendees with their mailing addresses

Report on Conference on Western Water Issues, 17-18 May 1979

Over the last few years several potential conflicts have emerged over the manner in which water is put to beneficial use in the western United States. These potential problems have been further heightened by the western drought of 1976-77 and by the recent upsurge of interest in developing western coal and oil-shale resources. The conference on Western Water Issues, held at the California Institute of Technology, 17-18 May 1979, provided a forum for representatives of industry, agriculture, government, environmental groups, research establishments and universities to exchange ideas on the subject. Most of the discussions centered on California and the Colorado River Basin. Specific items discussed included climatic fluctuations and predictability of the basic water supply; existing water law and needed changes; economics of water and the lack of real water markets; pending California state legislation (on the Peripheral Canal in the Sacramento-San Joaquin Delta area, and on limits to pumping overdrafted ground water basins); water availability for energy resources development; and competing needs by municipalities, industry, and agriculture. As a summary of the conference, this report should be regarded as a source book to clarify the issues and direct the reader to relevant individuals and references

Aggregate water availability for energy development in the upper Colorado River basin

Can a large (significant in national terms) energy-recovery industry be developed in the Upper Colorado River Basin (UCRB), alongside more traditional water uses, without causing a problem in the aggregate quantity of water supplied to the Lower Colorado River Basin?. This report answers that question in a "reasonably conservative" manner by slightly overpredicting demand and underpredicting supply. First, aggregate consumption of water in the UCRB due to water intensive energy industries is calculated as a function of the level of energy production. Reasonably conservative (i.e., on the high side) estimates of unit water requirements for coal-electric generation, coal-slurry pipelines, coal gasification (to produce substitute natural gas — SNG), and oil-shale processing are developed from an extensive literature survey. These are combined with various energy-development scenarios, also developed from a literature survey, to give total energy-related water consumption as a function of total energy industry size. Overall total UCRB water consumption can then be found by adding to the energy-related water use all non-energy-related consumption. On the supply side, aggregate UCRB water availability is determined from the results of a steady-state, stochastic hydrologic model which predicts the reliability of flow to the lower basin as a function of total UCRB consumption. Predictions of the model are conservative, in the sense of being on the low side, because: (1) the period of record used to determine tributary flows is a relatively low flow period and (2) because the use of excess stored water above steady-state levels during transition periods to steady state is ignored. Demand and supply are then presented together in a graphical form which allows the reader to determine for him-or-herself the level of energy development which can be allowed in the UCRB, depending on the levels he or she chooses for non-energy-related water consumption in the upper basin and the reliability of water supply to the lower basin. On an aggregate basis, there appears to be enough water available in the Upper Colorado River Basin to produce about 7 quads per year (7 x 10^(15) Btu/yr or 7.4 x 10^(18) J/yr, equivalent to well over one-half current liquid fuel imports) from the region's fossil fuel resources by water-intensive energy industries and still allow an increase in other water uses by more than 25% (about 0.8 million acrefeet per year (9.8x10^8 m^3/yr)) over what they now are

Masses, radii, and orbits of small Kepler planets : The transition from gaseous to rocky planets

We report on the masses, sizes, and orbits of the planets orbiting 22 Kepler stars. There are 49 planet candidates around these stars, including 42 detected through transits and 7 revealed by precise Doppler measurements of the host stars. Based on an analysis of the Kepler brightness measurements, along with high-resolution imaging and spectroscopy, Doppler spectroscopy, and (for 11 stars) asteroseismology, we establish low false-positive probabilities (FPPs) for all of the transiting planets (41 of 42 have an FPP under 1%), and we constrain their sizes and masses. Most of the transiting planets are smaller than three times the size of Earth. For 16 planets, the Doppler signal was securely detected, providing a direct measurement of the planet's mass. For the other 26 planets we provide either marginal mass measurements or upper limits to their masses and densities; in many cases we can rule out a rocky composition. We identify six planets with densities above 5 g cm-3, suggesting a mostly rocky interior for them. Indeed, the only planets that are compatible with a purely rocky composition are smaller than 2 R ⊕. Larger planets evidently contain a larger fraction of low-density material (H, He, and H2O).Peer reviewedFinal Accepted Versio

Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler

We report the distribution of planets as a function of planet radius (R_p), orbital period (P), and stellar effective temperature (Teff) for P < 50 day orbits around GK stars. These results are based on the 1,235 planets (formally "planet candidates") from the Kepler mission that include a nearly complete set of detected planets as small as 2 Earth radii (Re). For each of the 156,000 target stars we assess the detectability of planets as a function of R_p and P. We also correct for the geometric probability of transit, R*/a. We consider first stars within the "solar subset" having Teff = 4100-6100 K, logg = 4.0-4.9, and Kepler magnitude Kp < 15 mag. We include only those stars having noise low enough to permit detection of planets down to 2 Re. We count planets in small domains of R_p and P and divide by the included target stars to calculate planet occurrence in each domain. Occurrence of planets varies by more than three orders of magnitude and increases substantially down to the smallest radius (2 Re) and out to the longest orbital period (50 days, ~0.25 AU) in our study. For P < 50 days, the radius distribution is given by a power law, df/dlogR= k R^\alpha. This rapid increase in planet occurrence with decreasing planet size agrees with core-accretion, but disagrees with population synthesis models. We fit occurrence as a function of P to a power law model with an exponential cutoff below a critical period P_0. For smaller planets, P_0 has larger values, suggesting that the "parking distance" for migrating planets moves outward with decreasing planet size. We also measured planet occurrence over Teff = 3600-7100 K, spanning M0 to F2 dwarfs. The occurrence of 2-4 Re planets in the Kepler field increases with decreasing Teff, making these small planets seven times more abundant around cool stars than the hottest stars in our sample. [abridged]Comment: Submitted to ApJ, 22 pages, 10 figure

Kepler-21b: A 1.6REarth Planet Transiting the Bright Oscillating F Subgiant Star HD 179070

We present Kepler observations of the bright (V=8.3), oscillating star HD 179070. The observations show transit-like events which reveal that the star is orbited every 2.8 days by a small, 1.6 R_Earth object. Seismic studies of HD 179070 using short cadence Kepler observations show that HD 179070 has a frequencypower spectrum consistent with solar-like oscillations that are acoustic p-modes. Asteroseismic analysis provides robust values for the mass and radius of HD 179070, 1.34{\pm}0.06 M{\circ} and 1.86{\pm}0.04 R{\circ} respectively, as well as yielding an age of 2.84{\pm}0.34 Gyr for this F5 subgiant. Together with ground-based follow-up observations, analysis of the Kepler light curves and image data, and blend scenario models, we conservatively show at the >99.7% confidence level (3{\sigma}) that the transit event is caused by a 1.64{\pm}0.04 R_Earth exoplanet in a 2.785755{\pm}0.000032 day orbit. The exoplanet is only 0.04 AU away from the star and our spectroscopic observations provide an upper limit to its mass of ~10 M_Earth (2-{\sigma}). HD 179070 is the brightest exoplanet host star yet discovered by Kepler.Comment: Accepted to Ap

Characterizing the Cool KOIs III. KOI-961: A Small Star with Large Proper Motion and Three Small Planets

We present the characterization of the star KOI 961, an M dwarf with transit signals indicative of three short-period exoplanets, originally discovered by the Kepler Mission. We proceed by comparing KOI 961 to Barnard's Star, a nearby, well-characterized mid-M dwarf. By comparing colors, optical and near-infrared spectra, we find remarkable agreement between the two, implying similar effective temperatures and metallicities. Both are metal-poor compared to the Solar neighborhood, have low projected rotational velocity, high absolute radial velocity, large proper motion and no quiescent H-alpha emission--all of which is consistent with being old M dwarfs. We combine empirical measurements of Barnard's Star and expectations from evolutionary isochrones to estimate KOI 961's mass (0.13 +/- 0.05 Msun), radius (0.17 +/- 0.04 Rsun) and luminosity (2.40 x 10^(-3.0 +/- 0.3) Lsun). We calculate KOI 961's distance (38.7 +/- 6.3 pc) and space motions, which, like Barnard's Star, are consistent with a high scale-height population in the Milky Way. We perform an independent multi-transit fit to the public Kepler light curve and significantly revise the transit parameters for the three planets. We calculate the false-positive probability for each planet-candidate, and find a less than 1% chance that any one of the transiting signals is due to a background or hierarchical eclipsing binary, validating the planetary nature of the transits. The best-fitting radii for all three planets are less than 1 Rearth, with KOI 961.03 being Mars-sized (Rp = 0.57 +/- 0.18 Rearth), and they represent some of the smallest exoplanets detected to date.Comment: Accepted to Ap

HAT-P-30b: A TRANSITING HOT JUPITER ON A HIGHLY OBLIQUE ORBIT

We report the discovery of HAT-P-30b, a transiting exoplanet orbiting the V = 10.419 dwarf star GSC 0208-00722. The planet has a period P = 2.810595 [plus-minus] 0.000005 days, transit epoch T[subscript c] = 2455456.46561 [plus-minus] 0.00037 (BJD), and transit duration 0.0887 [plus-minus] 0.0015 days. The host star has a mass of 1.24 ± 0.04 M ⊙, radius of 1.21 [plus-minus] 0.05 R ⊙, effective temperature of 6304 [plus-minus] 88 K, and metallicity [Fe/H] = +0.13 [plus-minus] 0.08. The planetary companion has a mass of 0.711 [plus-minus] 0.028 M[subscript J] and radius of 1.340 [plus-minus] 0.065 R[subscript J] yielding a mean density of 0.37 [plus-minus] 0.05 g cm[superscript –3]. We also present radial velocity measurements that were obtained throughout a transit that exhibit the Rossiter-McLaughlin effect. By modeling this effect, we measure an angle of λ = 73fdg5 [plus-minus] 9fdg0 between the sky projections of the planet's orbit normal and the star's spin axis. HAT-P-30b represents another example of a close-in planet on a highly tilted orbit, and conforms to the previously noted pattern that tilted orbits are more common around stars with T[subscript eff*] gsim 6250 K.United States. National Aeronautics and Space Administration (NASA grant NNX09AF59G)United States. National Aeronautics and Space Administration (Kepler Mission under NASA Cooperative Agreement NCC2-1390)Hungarian Scientific Research Foundation (grant K-81373

An Accurate Mass Determination for Kepler-1655b, a Moderately Irradiated World with a Significant Volatile Envelope

Funding: A.C.C. acknowledges support from STFC consolidated grant number ST/M001296/1. The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant Agreement No. 313014 (ETAEARTH).We present the confirmation of a small, moderately-irradiated (F= 155±7 F⊕) Neptune with a substantial gas envelope in a P=11.8728787±0.0000085-day orbit about a quiet, Sun-like G0V star Kepler-1655. Based on our analysis of the Kepler light curve, we determined Kepler-1655b’s radius to be 2.213±0.082 R⊕. We acquired 95 high-resolution spectra with TNG/HARPS-N, enabling us to characterize the host star and determine an accurate mass for Kepler-1655b of 5.0±^3.1_2.8 M⊕ via Gaussian-process regression. Our mass determination excludes an Earth-like composition with 98% confidence. Kepler-1655b falls on the upper edge of the evaporation valley, in the relatively sparsely occupied transition region between rocky and gas-rich planets. It is therefore part of a population of planets that we should actively seek to characterize further.PostprintPeer reviewe