Rocketsonde

A sounding rocket, sometimes called a research rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The rockets are used to carry instruments from 30 to 90 miles (48 to 145 km) above the surface of the Earth, the altitude generally between weather balloons and satellites; the maximum altitude for balloons is about 25 mi (40 km) and the minimum for satellites is approximately 75 mi (121 km). Certain sounding rockets have an apogee between 620 and 930 miles (1,000 and 1,500 km), such as the Black Brant X and XII, which is the maximum apogee of their class. Sounding rockets often use military surplus rocket motors. NASA routinely flies the Terrier Mk 70 boosted Improved Orion, lifting 600–1,000-pound (270–450 kg) payloads into the exoatmospheric region between 60 and 125 miles (97 and 201 km). A sounding rocket, sometimes called a research rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The rockets are used to carry instruments from 30 to 90 miles (48 to 145 km) above the surface of the Earth, the altitude generally between weather balloons and satellites; the maximum altitude for balloons is about 25 mi (40 km) and the minimum for satellites is approximately 75 mi (121 km). Certain sounding rockets have an apogee between 620 and 930 miles (1,000 and 1,500 km), such as the Black Brant X and XII, which is the maximum apogee of their class. Sounding rockets often use military surplus rocket motors. NASA routinely flies the Terrier Mk 70 boosted Improved Orion, lifting 600–1,000-pound (270–450 kg) payloads into the exoatmospheric region between 60 and 125 miles (97 and 201 km). The origin of the term comes from nautical vocabulary to sound, which is to throw a weighted line from a ship into the water to measure the water's depth. The term itself has its etymological roots in the Portuguese, Italian, Spanish, and French words for probe, which are 'sonda' and 'sonde', respectively. Sounding in the rocket context is equivalent to taking a measurement. The basic elements of a sounding rocket are a solid-fuel rocket motor and a science payload. Larger, higher altitude rockets have two to three stages to increase efficiency and payload capability. The freefall part of the flight is an elliptic trajectory with vertical major axis allowing the payload to appear to hover near its apogee. The average flight time is less than 30 minutes; usually between five and 20 minutes. The rocket consumes its fuel on the first stage of the rising part of the flight, then separates and falls away, leaving the payload to complete the arc and return to the ground under a parachute. Sounding rockets are advantageous for some research because of their low cost, short lead time (sometimes less than six months) and their ability to conduct research in areas inaccessible to either balloons or satellites. They are also used as test beds for equipment that will be used in more expensive and risky orbital spaceflight missions. The smaller size of a sounding rocket also makes launching from temporary sites possible allowing for field studies at remote locations, and even in the middle of the ocean, if fired from a ship. Weather observations, up to an altitude of 75,000 m, are done with rocketsondes, a kind of sounding rocket for atmospheric observations that consists of a rocket and radiosonde. The latter one record data on temperature, moisture, wind speed and direction, wind shear, atmospheric pressure, and air density during the flight. Position data (altitude and latitude/longitude) may also be recorded. Common meteorological rockets are the Loki and Super Loki, typically a 3.7 m tall and powered by a 10 cm diameter solid fuel rocket engine. The rocket engine separates at an altitude of 1500 m and the rest of the rocketsonde coasts to apogee (highest point). This can be set to an altitude of 20,000 m to 113,000 m. Rocketsondes were used in the fictional television miniseries Category 7: The End of the World.