Recent Measurements of Experiment Sensitivity to G-Jitter and Their Significance to ISS Facility Development

1998 ◽  
Vol 551 ◽  
Author(s):  
R. A. Herring ◽  
B. Tryggvason
Keyword(s):  
International Space Station ◽  
Vibration Isolation ◽  
Space Shuttle ◽  
Space Station ◽  
Experimental Measurements ◽  
International Space ◽  
Microgravity Experiments ◽  
Experimental Facilities ◽  
Better Than

AbstractRecent experimental measurements of various microgravity experiments have been taken on the Mir and Space Shuttle under different conditions of microgravity using the Microgravity-vibration Isolation Mount (MIM). The results to date show a clear difference when the experimental measurements are taken from g-levels offered by the Mir and the Space Shuttle (non isolated) to g-levels offered by MIM (isolated) which have been reduced by two orders of magnitude. Concern for the International Space Station (ISS) experimental facilities arises when the quality of microgravity on the Mir and Space Shuttle (non isolated), which is believed to be not good enough, has been measured to be better than the ISS Requirement established by NASA for isolated racks, which will be significantly better than those racks not isolated.

scholarly journals Validation of stratospheric and mesospheric ozone observed by SMILES from International Space Station

2013 ◽  
Vol 6 (9) ◽  
pp. 2311-2338 ◽  
Author(s):  
Y. Kasai ◽  
H. Sagawa ◽  
D. Kreyling ◽  
E. Dupuy ◽  
P. Baron ◽  
...  
Keyword(s):  
International Space Station ◽  
Signal To Noise Ratio ◽  
Space Station ◽  
Local Times ◽  
International Space ◽  
Order Of Magnitude ◽  
Mesospheric Ozone ◽  
Synchronous Orbit ◽  
Better Than

Abstract. We observed ozone (O3) in the vertical region between 250 and 0.0005 hPa (~ 12–96 km) using the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) on the Japanese Experiment Module (JEM) of the International Space Station (ISS) between 12 October 2009 and 21 April 2010. The new 4 K superconducting heterodyne receiver technology of SMILES allowed us to obtain a one order of magnitude better signal-to-noise ratio for the O3 line observation compared to past spaceborne microwave instruments. The non-sun-synchronous orbit of the ISS allowed us to observe O3 at various local times. We assessed the quality of the vertical profiles of O3 in the 100–0.001 hPa (~ 16–90 km) region for the SMILES NICT Level 2 product version 2.1.5. The evaluation is based on four components: error analysis; internal comparisons of observations targeting three different instrumental setups for the same O3 625.371 GHz transition; internal comparisons of two different retrieval algorithms; and external comparisons for various local times with ozonesonde, satellite and balloon observations (ENVISAT/MIPAS, SCISAT/ACE-FTS, Odin/OSIRIS, Odin/SMR, Aura/MLS, TELIS). SMILES O3 data have an estimated absolute accuracy of better than 0.3 ppmv (3%) with a vertical resolution of 3–4 km over the 60 to 8 hPa range. The random error for a single measurement is better than the estimated systematic error, being less than 1, 2, and 7%, in the 40–1, 80–0.1, and 100–0.004 hPa pressure regions, respectively. SMILES O3 abundance was 10–20% lower than all other satellite measurements at 8–0.1 hPa due to an error arising from uncertainties of the tangent point information and the gain calibration for the intensity of the spectrum. SMILES O3 from observation frequency Band-B had better accuracy than that from Band-A. A two month period is required to accumulate measurements covering 24 h in local time of O3 profile. However such a dataset can also contain variation due to dynamical, seasonal, and latitudinal effects.

scholarly journals Validation of stratospheric and mesospheric ozone observed by SMILES from International Space Station

2013 ◽  
Vol 6 (2) ◽  
pp. 2643-2720 ◽  
Author(s):  
Y. Kasai ◽  
H. Sagawa ◽  
D. Kreyling ◽  
K. Suzuki ◽  
E. Dupuy ◽  
...  
Keyword(s):  
International Space Station ◽  
Signal To Noise Ratio ◽  
Space Station ◽  
Local Times ◽  
International Space ◽  
Calibration Problem ◽  
Order Of Magnitude ◽  
Synchronous Orbit ◽  
Better Than

Abstract. We observed the diurnal variation of ozone (O3) in the vertical region between 250 and 0.0005 hPa (~12–96 km) using the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) on the Japanese Experiment Module (JEM) of the International Space Station (ISS) between 12 October 2009 and 21 April 2010. The new 4 K superconducting heterodyne receiver technology of SMILES allowed us to obtain a one order of magnitude better signal-to-noise ratio for the O3 line observation compared to past spaceborne microwave instruments. We assessed the quality of the vertical profiles of O3 in the 100–0.001 hP (~16–90 km) region for the SMILES NICT Level 2 product version 2.1.5. The evaluation is based on four components; error analysis; internal comparisons of observations targeting three different instrumental setups for the same O3 625.371 GHz transition; internal comparisons of two different retrieval algorithms; and external comparisons for various local times with ozonesonde, satellite and balloon observations (ENVISAT/MIPAS, SCISAT/ACE-FTS, Odin/OSIRIS, Odin/SMR, Aura/MLS, TELIS). SMILES O3 data have an estimated absolute accuracy of better than 0.3 ppmv (3%) with a vertical resolution of 3–4 km over the 60 to 8 hPa range. The random error for a single measurement is better than the estimated systematic error, being less than 1, 2, and 7%, in the 40–1, 80–0.1, and 100–0.004 hPa pressure region, respectively. SMILES O3 abundance was 10–20% lower than all other satellite measurements at 8–0.1 hPa due to an error arising from uncertainties of the tangent point information and the calibration problem for the intensity of the spectrum. The non sun-synchronous orbit of the ISS allowed us to observe O3 at various local times. A two month period is required to accumulate measurements covering 24 h in local time. However such a dataset can also contain variation due to dynamical, seasonal, and latitudinal effects.

scholarly journals Shuttle diplomacy

2011 ◽  
Vol 133 (07) ◽  
pp. 46-53
Author(s):  
Burton Dicht
Keyword(s):  
International Space Station ◽  
Space Shuttle ◽  
Space Exploration ◽  
Space Station ◽  
Operating Costs ◽  
Space Program ◽  
International Space ◽  
New Vision ◽  
The Cost ◽  
The U.S

This article analyzes the decisions and technological challenges that drove the Space Shuttle’s development. The goal of the Shuttle program was to create a reusable vehicle that could reduce the cost of delivering humans and large payloads into space. Although the Shuttle was a remarkable flying machine, it never lived up to the goals of an airline-style operation with low operating costs. In January 2004, a year after the Columbia accident, President George W. Bush unveiled the “Vision for U.S. Space Exploration” to guide the U.S. space effort for the next two decades. A major component of the new vision, driven by the recommendations of the Columbia Accident Investigation Board, was to retire the Space Shuttle fleet as soon as the International Space Station assembly was completed. With cancellation of the Constellation program in 2010, the planned successor to the Shuttle, the U.S. space program is now in an era of uncertainty.

Concurrent-Flow Flame Spread Over a Thin Solid in a Narrow Confined Space in Microgravity

2019 ◽  
Author(s):  
Yanjun Li ◽  
Ya-Ting T. Liao ◽  
Paul Ferkul
Keyword(s):  
International Space Station ◽  
Flame Spread ◽  
Numerical Study ◽  
Space Station ◽  
Spread Rate ◽  
International Space ◽  
Concurrent Flow ◽  
Microgravity Experiments ◽  
Flame Spread Rate ◽  
Flow Duct

Abstract A numerical study is pursued to investigate the aerodynamics and thermal interactions between a spreading flame and the surrounding walls as well as their effects on fire behaviors. This is done in support of upcoming microgravity experiments aboard the International Space Station. For the numerical study, a three-dimensional transient Computational Fluid Dynamics combustion model is used to simulate concurrent-flow flame spread over a thin solid sample in a narrow flow duct. The height of the flow duct is the main parameter. The numerical results predict a quenching height for the flow duct below which the flame fails to spread. For duct heights sufficiently larger than the quenching height, the flame reaches a steady spreading state before the sample is fully consumed. The flame spread rate and the pyrolysis length at steady state first increase and then decrease when the flow duct height decreases. The detailed gas and solid profiles show that flow confinement has competing effects on the flame spread process. On one hand, it accelerates flow during thermal expansion from combustion, intensifying the flame. On the other hand, increasing flow confinement reduces the oxygen supply to the flame and increases conductive heat loss to the walls, both of which weaken the flame. These competing effects result in the aforementioned non-monotonic trend of flame spread rate as duct height varies. This work relates to upcoming microgravity experiments, in which flat thin samples will be burned in a low-speed concurrent flow using a small flow duct aboard the International Space Station. Two baffles will be installed parallel to the fuel sample (one on each side of the sample) to create an effective reduction in the height of the flow duct. The concept and setup of the experiments are presented in this work.

Evaluation of a Treadmill with Vibration Isolation and Stabilization (TVIS) for Use on the International Space Station

1999 ◽  
Vol 15 (3) ◽  
pp. 292-302 ◽  
Author(s):  
Jean L. McCrory ◽  
David R. Lemmon ◽  
H. Joseph Sommer ◽  
Brian Prout ◽  
Damon Smith ◽  
...  
Keyword(s):  
International Space Station ◽  
Vibration Isolation ◽  
Space Station ◽  
Lower Extremities ◽  
Structural Safety ◽  
Microgravity Environment ◽  
Zero Gravity ◽  
Experimental Conditions ◽  
International Space ◽  
Angular Displacements

A treadmill with vibration isolation and stabilization designed for the International Space Station (ISS) was evaluated during Shuttle mission STS-81. Three crew members ran and walked on the device, which floats freely in zero gravity. For the majority of the more than 2 hours of locomotion studied, the treadmill showed peak to peak Linear and angular displacements of less than 2.5 cm and 2.5°, respectively. Vibration transmitted to the vehicle was within the microgravity allocation limits that are defined for the ISS. Refinements to the treadmill and harness system are discussed. This approach to treadmill design offers the possibility of generating 1G-like loads on the lower extremities while preserving the microgravity environment of the ISS for structural safety and vibration free experimental conditions.

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