University of Hawaii at Manoa

About: University of Hawaii at Manoa is a education organization based out in Honolulu, Hawaii, United States. It is known for research contribution in the topics: Population & Sea surface temperature. The organization has 13693 authors who have published 25161 publications receiving 1023924 citations.

The Discovery of a Field Methane Dwarf from Sloan Digital Sky Survey Commissioning Data

Abstract: We report the discovery of the coolest field dwarf yet known, selected as an unresolved object with extremely red colors from commissioning imaging data of the Sloan Digital Sky Survey. Its spectrum from 0.8 to 2.5 μm is dominated by strong bands of H2O and CH4. Its spectrum and colors over this range are very similar to those of Gl 229B, the only other known example of a methane dwarf. It is roughly 1.2 mag fainter than Gl 229B, suggesting that it lies at a distance of ~10 pc. Such a cool object must have a mass well below the hydrogen-burning limit of 0.08 M☉ and therefore is a genuine brown dwarf, with a probable mass in the range 0.015-0.06 M☉ for an age range of 0.3-5 Gyr.

The many faces of RU486: tales of situated knowledges and technological contestations.

Abstract: In the highly contentious abortion arena, the new oral abortifacient technology RU486 is one among many actors. This article offers an arena analysis of the heterogeneous constructions of RU486 by various actors, including scientists, pharmaceutical compa nies, medical groups, antiabortion groups, women's health movement groups, and others who have produced situated knowledges. Conceptually, we find not only that the identity of the nonhuman actor-RU486 -is unstable and multiple but also that, in practice, there are other (previously invisible) implicated actors—the downstream users and consumers of the technology. If we try to follow all the actors, we find a fuller and more historicized arena, and, ironically, we too can be construed as implicated actors in it.

Temporal Structure of the Southern Oscillation as Revealed by Waveform and Wavelet Analysis

Abstract: Wavelet transforms (WLT) and waveform transforms (WFT) are effective tools that reveal temporal structure of nonstationary time series. The authors discuss principles and practical aspects of their geophysical applications. The WLT can display variance as a continuous function of time and frequency, but the frequency (time) locality reduces at the high (low) frequency bands. The WFT, on the other hand, provides a sharp view of the locality in both time and frequency, but presents variance by discrete base functions. The two techniques are complementary. The authors use both Morlet WLT and Gabor WFT to analyze temporal structure of the Southern Oscillation (50). The principal period of the SO has experienced two rapid changes since 1872, one in the early 1910s and the other in the mid-1960s. The dominant period was 3–4 years in the earliest four decades (1872–1910), 5–7 years in the ensuing five decades (1911–1960. except the 1920s), and about 5 years in the last two decades (1970–1992). Ale SO al...

From Kuiper Belt Object to Cometary Nucleus: The Missing Ultrared Matter

Abstract: We combine new and published data to show that the optical color distributions of cometary nuclei and Kuiper belt objects (KBOs) are significantly different. The nuclei are, as a group, bluer than the KBOs, indicating that the surface chemical and/or physical properties of the two types of bodies are different. Objects in the dynamically intermediate Centaur class have optical colors like those of KBOs, while the color distribution of candidate dead comets is indistinguishable from that of the cometary nuclei. We infer that the surfaces of KBOs are modified upon entry to the inner solar system. We consider several mechanisms and conclude that the color change is most likely caused by the rapid burial of ancient surface materials exposed in the Kuiper belt. The distinctive, ultrared material that is present on the surfaces of some KBOs is absent on the cometary nuclei.