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Research balloons are balloons that are used for scientific research. They are usually unmanned, filled with a lighter-than-air gas like helium, and fly at high altitudes. Meteorology, atmospheric research, astronomy, and military research may be conducted from a research balloon. Weather balloons are a type of research balloon. Research ...
As a result, a certain volume of gas has a lower density as the temperature is higher. The temperature of the hot air in the envelope will vary depending upon the ambient temperature, but the maximum continuous operating temperature for most balloons is 250 °F (121 °C). [2]
The ascent rate can be controlled by the amount of gas with which the balloon is filled, usually at around 300 metres per minute (980 ft/min). [ 9 ] : 24–54 Weather balloons may reach altitudes of 40 km (25 mi) or more, limited by diminishing pressures causing the balloon to expand to such a degree (typically by a 100:1 factor) that it ...
Helium also has a very low boiling point (-268.9°C or -452°F), allowing it to remain a gas even in super-cold environments, an important feature because many rocket fuels are stored in that ...
High-altitude balloons or stratostats are usually uncrewed balloons typically filled with helium or hydrogen and released into the stratosphere, generally attaining between 18 and 37 km (11 and 23 mi; 59,000 and 121,000 ft) above sea level. In 2013, a balloon named BS 13-08 reached a record altitude of 53.7 km (33.4 mi; 176,000 ft). [1]
There are five types of air pollution dispersion models, as well as some hybrids of the five types: [1] Box model – The box model is the simplest of the model types. [2] It assumes the airshed (i.e., a given volume of atmospheric air in a geographical region) is in the shape of a box.
The balloon and sensor often endure temperatures as low as 139 degrees below zero Fahrenheit, air pressures only a few thousandths of what is found on the Earth's surface, ice, rain, thunderstorms ...
Air pollution can occur naturally or be caused by human activities. [4] Air pollution causes around 7 or 8 million deaths each year. [5] [6] It is a significant risk factor for a number of pollution-related diseases, including heart disease, stroke, chronic obstructive pulmonary disease (COPD), asthma and lung cancer.