Earth earth collision or realization of NASA's plan to hit Gemini in 2021
4hw.com.cn: the science fiction film "collision between heaven and earth" tells that astronauts change the trajectory of comets by hitting comets in order to avoid comets hitting the earth. Recently, NASA will conduct similar experiments to hit Gemini.
On May 10, it was reported that the western media said that in the science fiction film "collision between heaven and earth" released in 1998, the astronauts finally succeeded in preventing the comet from directly hitting the earth, thus saving mankind at stake. Although a variety of methods to change the path of comets were initially tested, the comet was eventually deviated from its original orbit by sacrificing a spacecraft and astronauts, which prevented the occurrence of disasters. After the film became famous, many people have such questions: is the way in the film only suitable for fictional plots, or can it really avoid potential space collision? Now, we will be able to wait and see.
According to the website of Spanish newspaper abessay on May 8, the National Aeronautics and Space Administration (NASA) plans to make a similar attempt in the summer of 2021, using an aircraft to directly impact the double asteroid system 'Gemini' 11 million kilometers away from the earth. Of course, manned aircraft will not perform this task. The program, called "double asteroid orbit change test" (DART), is the first technical verification project designed by NASA to change its orbit to prevent asteroids from hitting the earth.
It is reported that the Gemini system consists of 'Gemini a' and its satellite 'Gemini B'. The former is about 780 meters in diameter and the latter is about 160 meters in diameter and flies around the former. They are not a threat to the earth and are ideal for testing the orbit changes of smaller planets around larger planets. The dart probe is scheduled to take off in June 2021 and is expected to hit 'Gemini B' in September 2022.
It is reported that the probe will deliberately hit 'Gemini B' at a speed of 6 km / s with the help of a camera installed on it and an advanced autonomous navigation software. Such a collision will change the speed of the small satellite in its orbit around the main celestial body by about 1%, which is enough to be measured by telescopes on earth.
It is reported that scientists have been observing the 'Gemini' system on the ground since 2015. At present, an international project is using powerful telescopes around the world to closely observe it, so as to fully understand the state of the double asteroid system before the dart mission. Scientists have got a lot of data and information to understand the system, but the understanding of the main object of dart mission 'Gemini B' is still insufficient.
In fact, it is unclear whether the dart probe will hit an asteroid composed of solid rock, loose debris or something 'softer' and more like sand. If it is the last option, the softer surface will absorb most of the force generated by the impact, so it will not be pushed as much as an asteroid composed of harder components, so it is difficult to achieve the desired effect. At present, scientists are conducting extensive modeling and simulation tests to help predict the impact.