Strange things in the universe

Did you know, in space, the candle flame burns in a sphere? People sweat more on earth? . These are completely strange facts in aerospace but little known, according to the statistics of Space page.

Strange facts in space

Water boils in a big bubble

On Earth, boiling water creates thousands of tiny bubbles. However, in space, it only creates a giant undulating bubble.

Fluid dynamics is so complex that physicists were not sure what would happen to boiling water in zero gravity until a final test was done in 1992 on a ship. shuttle. Later, physicists determined that the simpler aspect of boiling in space could result from the absence of convection and buoyancy - two phenomena caused by gravity. On Earth, these effects create the turbulence that we observe in the water kettle.

We can learn many things from these fluid boiling experiments. According to the Science News page of the US Space Agency (NASA): " Knowing how liquids boil in space will lead to improved cooling systems more efficiently for spacecraft . Article that could one day be used to design power plants for space stations, operating according to the mechanism of using sunlight to boil a liquid to create steam to turn a turbine to generate electricity . "

Fire burns in a sphere

On earth, the fire burns up vertically. But in space, they radiate in all directions.

Scientists explain this phenomenon as follows: The closer to the Earth's surface, the more air molecules are due to the planet's gravity holding them there. Conversely, the air becomes more and more thinner as you move vertically, causing a gradual decline in pressure. The difference in atmospheric pressure every 2.5cm, although small, is sufficient to form the shape of a candle flame.

Pressure difference causes an effect called natural convection. When the air around the flame heats up, it expands, becoming lighter than the cold air surrounding it. When hot gas molecules expand outside, cold gas molecules push back. On Earth, because there are more cold gas molecules that repel hot molecules at the base of the flame, at the top of the flames, there is less "antagonism". And so the flame rises vertically.

However, when there is no gravity (as in space), the expanding hot air faces " the opposite " in all directions, and therefore the fire forms a sphere out of the source. shining.

Bacteria grow more and more dangerous

Thirty years of experiments have shown that bacterial "colonies" grow much faster in space. For example, the colonies of E Coli bacteria (bacteria that cause many types of intestinal diseases) rapidly increase in space almost twice as much as the colonies of "colleagues" on earth.

In addition, some bacteria develop in a way that is more deadly. As a result of a 2007 controlled experiment to test the growth of salmonella (a pathogen and food poisoning) on ​​the space shuttle Atlantis, the space environment changed expression. Current of 167 bacterial genes. Studies conducted after the flight found that these genetic modifications increased salmonella's pathogenicity by nearly three times that of the same kind on Earth.

There are several theories that explain why bacteria grow stronger in a weightless environment. They can simply have more "land" to grow on earth. For changes in gene expression in salmonella, the scientists say, they may be the result of a stress response in a protein called Hfq, which plays a role in controlling expression. genes. Gravity creates mechanical stress on bacterial cells through changing the way fluids move on their surfaces. Hfq reacts by starting "survival mode", in which it makes cells more dangerous.

Through understanding how bacteria respond to stress in space, scientists hope to know how it can cope with stressful situations on Earth. For example, Hfq protein may undergo a similar stress response when salmonella bacteria are attacked by the human immune system.

You can't make beer

Because there is no gravitational force , which means that there is no floating force , nothing pushes the air bubbles up and out of the carbonated drinks in space. This means, simple carbon dioxide bubbles are trapped in fresh water and beer, even if they are in the astronauts' abdomen. In fact, without gravity , the astronauts could not fill the gas and that made carbonated drinks extremely unattractive.

Fortunately, an Australian company has brewed a special beer for outer space flights. This Vostok 4 Pines Stout Beer is rich in flavor, but has a low gas concentration. Astronauts4Hire, a nonprofit space research organization, is investigating whether this beer is safe to use in future commercial space flights.

Roses have a distinct smell

The flowers produce different aromatic compounds when growing in the universe, and therefore, the smell is completely different. This is because volatile oils produced by plants - fragrant oils - are strongly influenced by environmental factors such as temperature, humidity and age of flowers. In terms of their fragility, it is not surprising that micro gravity will also affect the production of vegetable oil.

The " outside of this world " scent caused by roses in the space, covering the Space Shuttle Discovery in 1998 was then analyzed, replicated and integrated into "Zen" - a product Shiseido Japanese cosmetics company.

You sweat more

As explained in the case of candle flame, zero gravity means that there is no natural convection. This means that the body temperature does not escape from the skin surface , so the body must constantly perspire to cool itself. Worse, because the lines of sweat don't drip or evaporate, they simply keep accumulating. It all makes the journey to conquer human space become quite wet, literally.