Research On Impact Effect To The Survive Rate Of Plant Seeds

The discovery of Martian meteorites "ALH84001" in1984in the South Pole,and the announcement that NASA had found early proof of the existence of thelife in the "ALH84001" Mars meteorite in1996,has led to the Panspermiahypothesis be back to our sight. Even if the evidence witch NASA says have notbeen prouded right, but the "ALH84001" meteorites can shuttled in two planetsfreely is the truth without any doubt.The Panspermia hypothesis suggests that life originated elsewhere but earth,and then travelled to earth via some trasfer mechanisms. In such a hypothesis,the life,includeing microorganisms and plant seeds, which origined in otherplanets, and lanched by some asteroids, micrometeoroids or cosmic dust, isorbiting the universe. Incidentally, it was caught by the solar system, and thenreached the earth, and becaming the origin life of the earth. If such a hypothesisdid happende, the microorganisms and the plant seeds shuold at least stay aliveafter reaching the surface of the earth and the impact when they reached theearth.In this paper,we use both experimental investigation and Ansys Autodynsimulation to study the impact of the Panspermia hypothesis. We use a light gasgun to do the experiment, and after doing this, we calcullate the germinationpercentage to discrabe whether or not it will survive in the impact an the surviverate.A program of experiment has carried out on plant seed,which are clover,alfalfa, turnip and water celery, testing for the germination percentage of themafter the hypervelocity impact. The experiment includes the projectile with seedsin it, which made of polycarbonate invasion of the water tank target and theflying plate impact the composite target with seeds loaded in it, to asimulate theprocess of the impact of the Panspermia hypothesis. We use the one stage lightgas gun of Hypervelocity of Impact Research Center.of Harbin Institute ofTechnologyIn the experiment of the projectile invasion of the water tank target, we usea lot of numerical simulation to describe the process of the impact,and obtain thesurvivel rate in different speed of two plant seeds at last.In the experiment of the flying plate impact the composite target with seedsin it, the divice of two cover plates over the groove will help us calculating theshock wave produced and the spread process easily. At the same time, we use PVDF and pressure sensor to measuring pressure signal, and explain thedestructure of the plate of the target.We obtain the difference of the destructure of the four plants seeds throughthe collection and the observation of the seeds after the impant. Then we get thecurve germination percentage-pressure by planting the seeds after the experiment,which we use to describe the survive rate. Finally, we compare difference of thesensitivity and the tolerance ability of these four type of plants seeds.