Msl1 Investigating Physical Science Phenomena

For MSL-1, the crew would indeed conduct a wide range of studies to unravel mysteries in three key areas: crystal growth, combustion and the development of techniques to produce stronger, more resilient metals and alloys. Moreover, as with several of Columbia's previous Spacelab missions, STS-83 was expected to evaluate some of the hardware, facilities and procedures that NASA expected to employ on board the International Space Station. It had already become clear from Shuttle research over the years that physical processes ordinarily masked by gravity on Earth were virtually eliminated in space, making it possible for scientists to conduct hitherto impossible experiments.

An important thrust of MSL-1's research was the ability to grow larger and purer crystals of proteins ranging from insulin to HIV-Reverse-Transcriptase and, in so doing, determining their three-dimensional structural 'blueprints'. By unlocking the crystals' structural details in this way, biochemists hoped to better understand how they fit in to the overall biology of the human body, but it has long been recognised that there are more than 300,000 proteins in our bodies, of which barely 1% are fully understood in structural terms.

It was anticipated that MSL-1's growth facilities would be capable of processing more than 1,500 protein crystal samples, perhaps ultimately helping to address the 'social costs' of illnesses and diseases - including cancer, diabetes, alcoholism, Alzheimer's and AIDS - which were estimated in 1997 to top $900 billion per year in the United States alone! Many of the proteins associated with these potential killers were the subject of most Shuttle crystal growth experiments, including those on board Halsell's mission.

Additional investigations focused on the differences of the combustion process in the microgravity environment, and its importance was highlighted by Linteris' inclusion on the STS-83 crew. It was hoped that developing a clearer understanding of the peculiarities of different types of fuel, and the fires they produce, could ultimately lead to increased efficiency and reduced emissions in internal-combustion

In the Operations and Checkout Building at KSC, the Spacelab module assigned to

STS-83 is prepared for movement to the OPF and installation on board Columbia.

In the Operations and Checkout Building at KSC, the Spacelab module assigned to

STS-83 is prepared for movement to the OPF and installation on board Columbia.

engines. In the United States, in 1997, the annual expenditure on crude oil was estimated by the American Petroleum Institute as close to $200 billion.

"Combustion in general is the major methodology for converting the chemical energy in fuel into useful thermal and mechanical energy,'' said Fred Dryer of Princeton University. "Combustion is also a major contributor to air pollution, including nitrogen oxides, carbon monoxide, unburned hydrocarbons and particu-lates. In addition, carbon dioxide - a greenhouse gas - is also produced by the combustion of hydrocarbons. It is relatively easy to produce very highly efficient conversion of the chemical energy in fuels to thermal or mechanical energy, particularly if there are no constraints with regards to emissions. It is much harder to optimise the conversion of thermal energy to useful mechanical energy, particularly with the constraints of emissions. Minimised emissions and best miles-per-gallon require us to carefully control and tailor the combustion process.'' Prior to MSL-1, this could only be done with sophisticated computers, but the experiments on Columbia provided an opportunity to analyse theoretical predictions and develop new models.

"The pieces of these models, then, can be fed into design codes for things such as engines and engine combustion and can help us improve the efficiency and emissions from those devices,'' said Dryer. For example, theories held that small fuel droplets should go through three separate 'regimes' during combustion. One of these, known as a 'quasi-steady state', has been frequently studied on the ground: the square of the

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