A scientific balloon being launched near Lynn Lake in [[Manitoba, Canada. The small amount of gas in the envelope expands to fill its 40-million-cubic-foot capacity as it climbs to reach the rarefied atmosphere at the balloon's cruise altitude of 23 miles. The 5,300-pound experiment is suspended from the launch crane whilst the balloon is being filled.]]
A gas balloon (also called a Charlier balloon for its inventor) is any balloon that stays aloft due to being filled with a gas less dense than air (such as
helium or
hydrogen. The first gas balloon made its flight in August 1789. It carried no passengers or cargo, and popped when it reached too high an altitude. Later that same year, a manned flight was made shortly after the first ascension in a
hot-air balloon (and indeed the first recorded ascension by man in any flying device).
Gas balloons remained popular throughout the age before powered flight. They could fly higher and farther than hot-air balloons, but were more dangerous as they were usually filled with hydrogen gas (which, unlike helium, could be easily mass-manufactured). Gas balloons were used in the
American Civil War, the
Napoleonic Wars (to very limited extent), and throughout the 19th century by hobbists and show performers such as the
Blanchards.
Today, gas balloons are filled with helium, which is not inflammable. Gas balloons are usually used for high-altitude research (such as with
weather balloons) and for record-breaking manned balloon flights.
Helium-filled balloons for scientific research have flown to altitudes more than 50 km above sea level, above Earth's
stratosphere and into the
mesosphere. Such balloons fly above over 99.9% of Earth's atmosphere and operate in near-
vacuum. They are used to image the
Sun and stars in
ultraviolet light that does not penetrate the atmosphere, to detect weak cosmic rays or the cosmic microwave background, or to study conditions at the top of the atmosphere.
Category:Balloons (aircraft)