4,855 research outputs found
Apollo experience report: Mission evaluation team postflight documentation
The various postflight reports prepared by the mission evaluation team, including the final mission evaluation report, report supplements, anomaly reports, and the 5-day mission report, are described. The procedures for preparing each report from the inputs of the various disciplines are explained, and the general method of reporting postflight results is discussed. Recommendations for postflight documentation in future space programs are included. The official requirements for postflight documentation and a typical example of an anomaly report are provided as appendixes
Development of user guidelines for ECAS display design, volume 1
Experiment computer application software (ECAS) display design and command usage guidelines were developed, which if followed by spacelab experiments, would standardize methods and techniques for data presentation and commanding via ECAS. These guidelines would provide some commonality among experiments which would enhance crew training and flight operations. The guidelines are applicable to all onboard experiment displays, whether allocated by ECAS or a dedicated experiment processor. A brief description of the spacelab data display system characteristics and of the services provided by the experiment computer operating system is included. Guidelines concerning data presentation and layout of alphanumeric and graphic information are presented along with guidelines concerning keyboard commanding and command feedback
H-alpha Activity of Old M Dwarfs: Stellar Cycles and Mean Activity Levels For 93 Low-Mass Stars in the Solar Neighborhood
Through the McDonald Observatory M Dwarf Planet Search, we have acquired
nearly 3,000 high-resolution spectra of 93 late-type (K5-M5) stars over more
than a decade using HET/HRS. This sample provides a unique opportunity to
investigate the occurrence of long-term stellar activity cycles for low-mass
stars. In this paper, we examine the stellar activity of our targets as
reflected in the H-alpha feature. We have identified periodic signals for 6
stars, with periods ranging from days to more than 10 years, and find long-term
trends for 7 others. Stellar cycles with P > 1 year are present for at least 5%
of our targets. Additionally, we present an analysis of the time-averaged
activity levels of our sample, and search for correlations with other stellar
properties. In particular, we find that more massive, earlier type (M0-M2)
stars tend to be more active than later type dwarfs. Furthermore,
high-metallicity stars tend to be more active at a given stellar mass. We also
evaluate H-alpha variability as a tracer of activity-induced radial velocity
(RV) variation. For the M dwarf GJ 1170, H-alpha variation reveals stellar
activity patterns matching those seen in the RVs, mimicking the signal of a
giant planet, and we find evidence that the previously identified stellar
activity cycle of GJ 581 may be responsible for the recently retracted planet f
(Vogt et al. 2012) in that system. In general, though, we find that H-alpha is
not frequently correlated with RV at the precision (typically 6-7 m/s) of our
measurements.Comment: Submitted to ApJ. Reflects comments from a positive refere
Multi-transition study and new detections of class II methanol masers
We have used the ATNF Mopra antenna and the SEST antenna to search in the
directions of several class II methanol maser sources for emission from six
methanol transitions in the frequency range 85-115 GHz. The transitions were
selected from excitation studies as potential maser candidates. Methanol
emission at one or more frequencies was detected from five of the maser
sources, as well as from Orion KL. Although the lines are weak, we find
evidence of maser origin for three new lines in G345.01+1.79, and possibly one
new line in G9.62+0.20.
The observations, together with published maser observations at other
frequencies, are compared with methanol maser modelling for G345.01+1.79 and
NGC6334F. We find that the majority of observations in both sources are
consistent with a warm dust (175 K) pumping model at hydrogen density ~10^6
cm^-3 and methanol column density ~5 x 10^17 cm^-2. The substantial differences
between the maser spectra in the two sources can be attributed to the geometry
of the maser region.Comment: 13 pages, 6 figures, Accepted for publication in MNRA
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