 |
It is a very lucky thing for us that the planet Jupiter is in our solar system and placed exactly where it is. I say this because it has been hit by asteroids and space debris on a regular basis and much of this stuff, if it wasn't intercepted, may have hit the earth. In 1994 there was a comet named Shoemaker-Levy 9 that collided with Jupiter. The resulting impact would have been devastating if it happened on earth. In July Jupiter looked like it was hit again. When Shoemaker-Levy 9 hit Jupiter it was important to note the size of the impacts. Jupiter's radius is the size of 11.209 earths. That means that its diameter is about 22.4 earths in size. Why do I think that this is important? There are several reasons, the first is that it is so big it attracts a lot of rocks heading our way and the second reason is that now you have something to compare the size of the impacts to. To me some of them look to be the size of the entire earth. Jupiter is interesting in other ways. It has a surface area that is equal to the area of almost 122 planet earths. Its mass is equal to about 318 earths. We know that it is a gas planet and no one is exactly sure how deep the gas goes before hitting the core. While it takes an escape velocity of 11.2 Kilometers per second to escape earth's gravity, it would take a ship that was on Jupiter a speed of 59.5 Kilometers per second to escape the gravity of Jupiter. There is a theory that states that the temperature at the core of Jupiter is hotter than the surface of the sun. This has yet to be proved however. A storm has been raging on Jupiter for hundreds of years and it can be seen through a telescope. The storm is known as THE GREAT RED SPOT. So far 63 moons have been associated with the planet Jupiter, that is the most of any planet in our solar system. Jupiter has a surface temperature of about 160 degrees Kelvin, but according to scientific calculations the temperature should only be 100 degrees Kelvin. It is thought that the discrepancy is due to the fact that Jupiter contracts and expands, thus creating extra heat.
Europa's Icy Surface As big as Jupiter is, we are finding many extrasolar planets that are much bigger. Jupiter has a density of a little above water. It has a magnetic field much stronger than the earth. It is doubtful that Jupiter will ever be the target of colonization by humans since it is so inhospitable and has no surface strong enough to support structures or even us. On top of this Jupiter has so much radiation that even probes that approach it that get too near will be zapped and put out of commission. While Jupiter itself is not a target for human colonization, this may not be true for some of its moons. Scientists are very interested in one of Jupiter's moons name Europa. The problem of Jupiter's radiation complicates plans to explore this moon. To combat this, scientists are trying to prepare a map of Jupiter's radiation belts so that they may better plan for trips to the moons. One scientist stated, "Our goal is to find some areas that might be interesting for a future mission to explore...". There is this feeling that Europa might be a candidate for microbial life. The map will be accompanied by a study to determine how detrimental Jupiter's radiation is to its moon. Maps are also being created of Europa and Ganymede.
Ganymede Jupiter is sort of like a little solar system of its own with Jupiter at the center and its 63 moons circling the planet. The reason that scientists are so interested in Europa and Ganymede is that they believe that below their icy surfaces are oceans and it is believed that if water exists than the chance to find life is greatly increased. This is based solely on earthly experience and it could turn out that this theory while correct here is not correct out there. Scientists believe that there are paths to the ocean where it would not be necessary to bore through miles of ice. How many miles is unknown. The pathways are known as chaos. It is believed that the chaos ridges are where warmer water may have seeped up to the surface creating a direct path down to the ocean. It is also believed that if the chaos is from the ocean then it might contain “molecular evidence for life in the ocean.” If moons are considered, we have a lot of places that we will have to explore right here in our own solar system, before launching out into the galaxy. We also have a lot of mysteries to try and explain, but I will hold off on those for another day. It could turn out that many miles of ice might protect life in an underground ocean from the harsh radiation of Jupiter, or it could turn out that what we consider harmful and deadly radiation will not harm life that has adapted to it. This would not be as unusual as it sounds. Insects on earth are a lot more able to survive doses of radiation that would be lethal to humans. Here is an example. People that were in an area near Hiroshima that received 1200 rads of radiation died slow deaths. On the other hand wood-boring insects that received up to 68,000 rads didn't show any effects from the radiation at all. I think that this is an import consideration when thinking about exploring planets and moons that are giving off radiation or being bombarded with it. I would just like to mention the fact that everything you heard about the roach surviving radiation is not true, it can only survive a little more radiation than we can and doesn't measure up to other insects in this area.
|
