If you could be in the stratosphere, you might well imagine being in space.
The sky is almost black even during the day, the surrounding horizon is clearly curved and without a space suit or other protection, you would quickly die from lack of oxygen and the Sun’s strong ultraviolet radiation.
By definition, the stratosphere is the part of the atmosphere that starts at about 15 kilometers and reaches about 50 kilometers.
The most interesting part of it is around 30 and 40 kilometers, because it is relatively easy and cheap to get there with the help of gas balls. From there you can look out into space almost like from satellites, you can study the atmosphere excellently there and the view down from there is great.
Airplanes can fly up to a height of about 25 kilometers before the air is so thin that the wings cannot support it and the jet engines cannot produce thrust. Satellites, on the other hand, fly forward in their orbits, which means that they are unable to focus on observations just above certain areas.
The Stratosphere is the strawberry patch in between. It’s actually a wonder that, in addition to researchers, others are only now interested in it.
Research balls are in the air even now
Balloons are basically the simplest flying devices. When lighter-than-air gas or hot air is put into the ball, the ball will rise up in the atmosphere just like a bubble in water.
Balloons were the only way to take off in the 19th century and in the 20th century they have been the only way to go high.
Balloons reached their peak, concretely and otherwise, in the 1950s, when, in the spirit of the Cold War and the beginning of the space age, the great powers studied the nature of the upper atmosphere and human activity at high altitudes.
After that, scientists, especially French and American ones, were mainly interested in high-altitude balling.
– The French national space research center CNES has been using balls for almost 60 years, he says Vincent Dubourgdeputy director of CNES’s stratospheric sphere department.
– We have designed, manufactured and operated ball systems for scientific and technological needs. They are used, for example, for atmospheric research, because we can make measurements and take samples on site at different heights in the atmosphere.
They can also be used to accurately map the winds with which the ball moves, and to study the radiation coming from space. Cell samples are sometimes put aboard the spheres, whose reactions to space radiation are studied.
– With the help of the balls, telescopes with a mass of up to a ton can be taken to a height of about 40 kilometers, and they can be used to make observations for several days or even months almost as well as with satellites.
In CNES’s ball laboratory in Toulouse, several levees are under construction, which will be raised to heights with large balloons. They are prepared for their flights almost like satellites for launch.
Since they can be recovered after the flights and can be used again, and since the price of Ballon Flight is significantly cheaper than a space launch, stratospheric flights typically use more modern and even experimental research equipment.
Many instruments that will later be put on satellites are first tested with balloon flights.
The largest payloads are tons in mass, and the balls carrying them are the size of a football stadium. Such flights are made only a couple of times a year.
Smaller pallets of around 500 kilograms are sent more often, five to six times a year. Balloon flights are made from sparsely populated areas, for example in Canada, the United States, Argentina and also in Swedish Lapland, Kiruna.
Balls sent from Kiruna are often directed to land in a controlled manner on the Finnish side in Lapland. The shelves are retrieved and reused.
US scientists make the same number of such flights, and Indian, Japanese and other Europeans make slightly less. The Russians and Chinese also make flights, but the number is unknown.
Roughly speaking, a major or major scientific or technical balloon flight is taking place somewhere around the globe every week. Smaller flights are made more often, and when you also include weather observation balloons rising into the stratosphere, there is always a buzz in the upper atmosphere.
High-pressure balloons are flown for three months
The most typical type of ball is a ball similar to regular rubber balloons sold in stores, only larger and made of a better rubber material than toy balls. The largest such ones have a volume of up to 400,000 cubic meters, i.e. the size of a stadium.
When they go into the air, they look modest, because they seem to have too little helium or hydrogen pumped into them. This is because as you go up, the density of the air drops and the sphere expands until at its height they are gigantic in size.
Flights made with such balloons last from hours to days. At the right time, over an uninhabited area, the rope supporting the plane from the ball is cut by remote control, and the plane descends with a parachute.
At the beginning of the 2000s, the French began to develop high-pressure balloons, whose size does not change at all according to the surrounding air pressure. As the name suggests, the pressure inside them is higher, and the pressurization is adjusted with the included equipment.
These balloons can be used for flights lasting several months, and their flight height can be kept quite constant. A more traditional ball rises and falls slightly as night and day change.
When the first pictures of the probable Chinese spy ball were published at the end of January, it was also noticed in France that the technology they developed has been put into use in China. In addition to the appearance, the long flight time indicated a high-pressure balloon.
However, the transition of research balloons to military use was not a surprise.
– We researchers have been able to operate in the stratosphere pretty much alone until now, and not much attention has been paid to our activities, says Vincent Dubourg.
– Many others have now also noticed the possibilities of the stratosphere. Controllable airships in particular, which can stay over a certain area or move as desired, are interesting both from the point of view of rescue and defense.
In addition to reconnaissance, these can also be used, for example, for monitoring forest fires and remote mapping.
The devices in the stratosphere can also be used to create data networks in areas where there are no mobile networks. The same trick is also of interest to soldiers, because if, for example, satellite connections are disrupted, they would be able to create their own connections.
– CNES only conducts scientific research, but we share our know-how with commercial operators. There are also several defense technology companies in Europe that develop aircraft that move and stay in the stratosphere.
So the soldiers are invading the stratosphere of the researchers’ playground. But so are tourists. Several companies are developing gondolas that could be lifted to the frontiers of space and that would come back down with parachutes. Almost space tourists could admire our beautiful home planet while enjoying champagne.