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Shamim Ansary:
How Does NASA Brew Beer In Space, What Does Space Beer Taste Like, and How Do You Drink a Coke In Space?
NASA is indeed interested in the questions raised by brewing beer in a microgravity environment.
Scientists who study the physics of gas-liquid mixtures would like to understand, for example, what happens when there is no buoyancy to bring the bubbles to the surface of a fizzy liquid, and the characteristics of fermentation in microgravity.
Two separate space shuttle experiments tackled these questions.
The first investigated how well yeast performs in orbital free fall, not only to see if brewing space-beer might be possible, but also to provide valuable information to pharmaceutical companies with a keen interest in the biology of orbiting microbes.
The space-beer turned out essentially the same as that brewed on Earth.
Its specific gravity and the yeast’s performance when used to brew subsequent batches of beer was comparable to that of control samples on Earth.
However, the total yeast cell count and the percentage of live cells in the space sample were lower. Despite this, the fermentation was significantly more efficient.
This raises the question of whether we can modify the fermentation process, or the yeast itself, to reproduce this effect on Earth.
The second experiment, flown on the shuttle by the Coca-Cola Company, was to test its system for dispensing Coke in a weightless environment.
The challenge was to dispense a fizzy beverage yet keep the gas in solution until the cola is drunk. Because bubbles don’t rise in free-fall, changes in temperature, pressure, or even physical agitation tend to cause the whole thing to degenerate into a foamy mess.
A computer-controlled device adjusted the temperature of the drink during mixing and dispensing, and minimized agitation by dispensing the drink into a collapsible bag inside a pressurized bottle.
The pressure around the bag was slowly released as it filled with drink, keeping the drink under constant pressure and preventing the gas from coming out of solution too quickly.
The end result was a space version of the world-famous fizzy drink.
Shamim Ansary:
Why Did NASA Put the Hubble Space Telescope In Space and Why Do Space Telescopes Take Sharper Images?
Since telescopes were first used by Galileo in the early seventeenth century, astronomers have dreamed of placing them where Earth’s atmosphere would not get in the way of viewing the universe.
The Hubble Space Telescope (HST) fulfills that dream.
The Hubble Space Telescope, a reflecting telescope, is not the largest telescope made on Earth.
Its amazing clarity comes from its position beyond the distorting interference of Earth’s atmosphere.
Hubble’s earth orbit also allows it to take extremely sharp images with almost no background light.
The HST has a primary mirror that is 7.9 feet (2.4 m) in diameter.
In addition to the telescope unit itself, the Hubble Space Telescope has two cameras, two spectrometers, to break up the components of light, and a photometer, to measure brightness.
Its control system for locating stars uses gyroscopes and special star-tracking and sensor devices.
The Hubble Space Telescope is NASA’s baby, but an international effort went into its construction and outfitting.
In return for the help, other countries get observation time using the HST.
Shamim Ansary:
Can the Hubble Space Telescope See the End of the Universe?
The space telescope Hubble that was put in orbit in 1990 is able to see seven times farther into space than any other telescope.
The space telescope was carried into orbit by the space shuttle. It is 45 feet long and consists of five separate astronomical instruments.
Astronomers expect to be able to zoom in on many things they do not now understand, such as quasars, pulsars, and black holes. Astronomers are wondering whether or not they will actually be able to see the ends of the universe.
The space telescope will provide us with a clearer picture of the heavens for two basic reasons. First, it will be beyond the dust in our atmosphere, so that its pictures will be much clearer. Second, some of the light from outer space is “screened†out by our atmosphere, which means that some information from distant stars and galaxies is not “getting through†to us.
The Hubble telescope is able to see everything much clearer than telescopes on earth.
Shamim Ansary:
Why Do Stars Always Appear to Rise In the East and Set In the West and What Is a Circumpolar Star?
Many of the stars you will see in the night sky follow a path across the sky from horizon to horizon.
Circumpolar stars, however, appear to circle the northern and southern celestial poles without ever rising or setting.
This is because the celestial sphere appears to rotate on the axis between its poles, in fact, it is Earth that is rotating on its axis.
If you draw a circle around the celestial pole in your hemisphere, the North Star in the Northern Hemisphere, at a distance equal to the number of degrees of your latitude, the stars within that circle remain above your celestial horizon all night.
For example, if you are stargazing at 40° latitude, any stars within a 40° radius of the North Star do not rise or set, but are always visible traveling around the celestial pole.
Shamim Ansary:
What Was Wrong With the Hubble Space Telescope When It Was First Put Into Orbit?
An error (1/50th the thickness of a human hair) in the curvature of the main mirror caused major focusing problems for the Hubble Space Telescope.
The 2.4 meter (94.5 inch) diameter mirror, was not able to focus all the light it collected to the correct point in the telescope.
NASA suffered great embarrassment for this multi-million dollar mistake.
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