Institution
Jet Propulsion Laboratory
Facility•La Cañada Flintridge, California, United States•
About: Jet Propulsion Laboratory is a facility organization based out in La Cañada Flintridge, California, United States. It is known for research contribution in the topics: Mars Exploration Program & Telescope. The organization has 8801 authors who have published 14333 publications receiving 548163 citations. The organization is also known as: JPL & NASA JPL.
Topics: Mars Exploration Program, Telescope, Galaxy, Coronagraph, Planet
Papers published on a yearly basis
Papers
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TL;DR: In this paper, a series of additional cosmological constraints on the shape and amplitude of the density power spectrum, the Hubble parameter and from supernovae were applied to further refine the cosmology parameters.
Abstract: We report an investigation of cosmological parameters based on the measurements of anisotropy in the cosmic microwave background radiation (CMB) made by ACBAR. We use the ACBAR data in concert with other recent CMB measurements to derive Bayesian estimates of parameters in inflation-motivated adiabatic cold dark matter models. We apply a series of additional cosmological constraints on the shape and amplitude of the density power spectrum, the Hubble parameter and from supernovae to further refine our parameter estimates. Previous estimates of parameters are confirmed, with sensitive measurements of the power spectrum now ranging from \ell \sim 3 to 2800. Comparing individual best model fits, we find that the addition of \Omega_\Lambda as a parameter dramatically improves the fits. We also use the high-\ell data of ACBAR, along with similar data from CBI and BIMA, to investigate potential secondary anisotropies from the Sunyaev-Zeldovich effect. We show that the results from the three experiments are consistent under this interpretation, and use the data, combined and individually, to estimate \sigma_8 from the Sunyaev-Zeldovich component.
122 citations
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TL;DR: During the encounter between Mariner IV and Mars on 14-15 July, no magnetic effect that could be definitely associated with the planet was evident in the magnetometer data, which implies that the Martian magnetic dipole moment is, at most, 3 x 10-4 times that of the earth.
Abstract: During the encounter between Mariner IV and Mars on 14-15 July, no magnetic effect that could be definitely associated with the planet was evident in the magnetometer data. This observation implies that the Martian magnetic dipole moment is, at most, 3 x 10^(-4) times that of the earth.
121 citations
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24 Aug 1981TL;DR: A NASA/ASEE Summer Study conducted at the University of Santa Clara in 1980 examined the feasibility of using advanced artificial intelligence and automation technologies in future NASA space missions as mentioned in this paper, including an intelligent Earth-sensing information system, autonomous space exploration system, an automated space manufacturing facility, and a self-replicating, growing lunar factory.
Abstract: A NASA/ASEE Summer Study conducted at the University of Santa Clara in 1980 examined the feasibility of using advanced artificial intelligence and automation technologies in future NASA space missions. Four candidate applications missions were considered. (1) An intelligent Earth-sensing information system, (2) an autonomous space exploration system, (3) an automated space manufacturing facility, and (4) a self-replicating, growing lunar factory. The study assessed the various AI and machine technologies which must be developed if such sophisticated missions are to become feasible by century's end.
121 citations
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TL;DR: In this paper, the results of investigation of the cloud top morphology performed by the VMC during more than 3 years of the Venus Express mission are presented. But, the authors focus on the data from the ultraviolet channel, centered at the characteristic wavelength of the unknown UV absorber that yields the highest contrasts on the cloud-top.
121 citations
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Environment Canada1, University of Wollongong2, Commonwealth Scientific and Industrial Research Organisation3, Earth System Research Laboratory4, Cooperative Institute for Research in Environmental Sciences5, Jet Propulsion Laboratory6, Ford Motor Company7, Goddard Space Flight Center8, Harvard University9, Swiss Federal Laboratories for Materials Science and Technology10, ETH Zurich11, Belgian Institute for Space Aeronomy12, National Center for Atmospheric Research13, Cooperative Institute for Mesoscale Meteorological Studies14, University of Toronto15, Geophysical Fluid Dynamics Laboratory16, Princeton University17, National Oceanic and Atmospheric Administration18
TL;DR: In this paper, various ozone measurement methods and ozone datasets are reviewed and selected for inclusion in the historical record of background ozone levels, based on relationship of the measurement technique to the modern UV absorption standard, absence of interfering pollutants, representativeness of the well-mixed boundary layer and expert judgement of their credibility.
Abstract: From the earliest observations of ozone in the lower atmosphere in the 19th century, both measurement methods and the portion of the globe observed have evolved and changed. These methods have di erent uncertainties and biases, and the data records di er with respect to coverage (space and time), information content, and representativeness. In this study, various ozone measurement methods and ozone datasets are reviewed and selected for inclusion in the historical record of background ozone levels, based on relationship of the measurement technique to the modern UV absorption standard, absence of interfering pollutants, representativeness of the well-mixed boundary layer and expert judgement of their credibility. There are signi cant uncertainties with the 19th and early 20th-century measurements related to interference of other gases. Spectroscopic methods applied before 1960 have likely underestimated ozone by as much as 11% at the surface and by about 24% in the free troposphere, due to the use of di ering ozone absorption coe cients.
There is no unambiguous evidence in the measurement record back to 1896 that typical mid-latitude background surface ozone values were below about 20 nmol mol–1, but there is robust evidence for increases in the temperate and polar regions of the northern hemisphere of 30–70%, with large uncertainty, between the period of historic observations, 1896–1975, and the modern period (1990–2014). Independent historical observations from balloons and aircraft indicate similar changes in the free troposphere. Changes in the southern hemisphere are much less. Regional representativeness of the available observations remains a potential source of large errors, which are di cult to quantify.
The great majority of validation and intercomparison studies of free tropospheric ozone measurement methods use ECC ozonesondes as reference. Compared to UV-absorption measurements they show a modest (~1–5% ±5%) high bias in the troposphere, but no evidence of a change with time. Umkehr, lidar, and FTIR methods all show modest low biases relative to ECCs, and so, using ECC sondes as a transfer standard, all appear to agree to within one standard deviation with the modern UV-absorption standard. Other sonde types show an increase of 5–20% in sensitivity to tropospheric ozone from 1970–1995.
Biases and standard deviations of satellite retrieval comparisons are often 2–3 times larger than those of other free tropospheric measurements. The lack of information on temporal changes of bias for satellite measurements of tropospheric ozone is an area of concern for long-term trend studies.
121 citations
Authors
Showing all 9033 results
Name | H-index | Papers | Citations |
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B. P. Crill | 148 | 486 | 111895 |
George Helou | 144 | 662 | 96338 |
H. K. Eriksen | 141 | 474 | 104208 |
Charles R. Lawrence | 141 | 528 | 104948 |
W. C. Jones | 140 | 395 | 97629 |
Gianluca Morgante | 138 | 478 | 98223 |
Jean-Paul Kneib | 138 | 805 | 89287 |
Kevin M. Huffenberger | 138 | 402 | 93452 |
Robert H. Brown | 136 | 1174 | 79247 |
Federico Capasso | 134 | 1189 | 76957 |
Krzysztof M. Gorski | 132 | 380 | 105912 |
Olivier Doré | 130 | 427 | 104737 |
Mark E. Thompson | 128 | 527 | 77399 |
Clive Dickinson | 123 | 501 | 80701 |
Daniel Stern | 121 | 788 | 69283 |