Page 12 - Curriculum Visions Dynamic Book

 An artist’s impression of what
the upper Jovian atmosphere might have looked like as the small surface probe floated down from Galileo
to investigate the atmosphere. The probe has its heat shield below and a parachute above.
The wok-shaped probe sent information to the orbiter for 57.6 minutes as it dropped about 200 kilometres through the atmosphere before succumbing to atmospheric pressure about 23 times greater than the average at Earth’s sea level.
Jupiter’s core is also the source of its heat. The heat may spread out evenly in all directions, warming the atmosphere from below and causing convection currents in the atmosphere. This source of convection is very different than on Earth, where little heat escapes from the core, and most heat in the atmosphere is soaked up by the land and oceans after radiation from the Sun. More heat is absorbed at the equator than at the poles, which causes air to flow between the equator and poles. On Jupiter, without any Sun heating thanks to its remoteness and with no temperature contrast between the poles and the equator, there may be no force to drive the eddies from one latitude to the other
as there is on Earth. Rather, the contrasts might be most intense between the lower and upper atmospheres.
atmospheric pressure The pressure on the gases in the atmosphere caused by gravity pulling them toward the centre of a celestial body.
convectioncurrents Thecirculating flow in a fluid (liquid or gas) that occurs when it is heated from below.
galileo A U.S. space probe launched in October 1989 and designed for intensive investigation of Jupiter.
heat shield A protective device on the outside of a space vehicle that absorbs the heat during reentry and protects it from burning up.
radiation The transfer of energy in the form of waves (such as light and heat) or particles (such as from radioactive decay of a material).
For more on the Galileo mission see “Outer worlds” in Volume 6: Journey into space.
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