Before launching the rocket, please count down tens of seconds

  Every time I saw the rocket launch on TV, it would affect the hearts of every audience. And that exciting moment often comes with ten, nine, eight, seven … the countdown sounds. Therefore, many people are very curious about why the countdown is used when the rocket is launched. In fact, this is not an invention of scientists, but a pioneering work of science fiction movies.
  In 1929, the German film master Fritz Lang presented for the first time the entire process of launching a moon landing rocket to the audience in his science fiction film “Chang Yue ‘in the Moon.” Because the process of delivering the rocket to the launch platform before the launch of the movie is too long, in order to attract the audience’s attention and create a dramatic atmosphere of “time urgency”, the movie specially arranged the protagonist to count down the countdown for the rocket to fire. But the real use of the countdown when the rocket is launched is not simply a tribute to the movie, but has practical significance. It is used to confirm the time zero of the rocket launch.
  From the rocket launcher to the completion of the mission, if the time axis is used as the number axis, then the launch time can be used as the zero point of the number axis, which is named T0. Time T0 is very important for orbit calculation. When the rocket is launched, time T0 will be automatically transmitted to all measurement and control stations. In the mission planning before the rocket launch, confirm T0 in the launch window (the optimal launch time of the mission), and determine the program settings before launch (expressed by T-xx time) and after launch (expressed by T + xx time) Is the top priority of the entire plan.
  After the planning is completed, the department in charge of the rocket launch will push back the completion time of various processes and components from T0, and continue to push forward according to the respective time of each department. Afterwards, the various departments of the rocket launch continued to sum up from months, weeks, and days when they completed their missions, to hours, hours, half hours, quarters, five minutes, one minute before the launch … until the order The staff read out the last ten numbers before T0 and summarized the tasks of all staff in the most extreme and most vivid way. This is the most complete manifestation of the countdown to rocket launch.
  In addition, it is worth mentioning that there are differences in the specific settings of the countdown for rocket launches. For example, China’s rocket countdown is an ignition countdown, and the rocket ignition time is used as T0. The rockets in the United States all use the countdown of takeoff, and take the rocket takeoff time as T0.

  From the perspective of living individuals, the key years that we can control are only a few decades, and then there is no second chance. For a person’s life, that is an opportunity, and time never comes. Life is so precious and miraculously beautiful for his ephemeral and irreversible, one-time and precious, how stupid it is to waste such a life!
  Maybe you ca n’t make a name for history, but at least you should be worthy of yourself for only a few decades; maybe you have failed to make virtue, meritorious deeds, but at least have fully exerted the energy of your life; maybe your efforts have not Can work, for example, business has never been successful, joined the army but eventually lost the battle, but the day of the final checkout, you can at least say that I did my best.
  If you do your best, you will be able to enjoy all the possibilities after your best efforts, even if it is the sense of sorrow and heroism of “I die in heaven, and sin of non-war”. You enjoy the fun that you do your best, and you can at least get a sense of fulfillment and accomplishment, and you will win, and you will certainly win. First of all, it is not others, but your own respect and satisfaction.
  Life is a process, a period of time, an energy release reaction, focusing on participation, investment, and effort. The victory is gratifying, and the defeat is still glorious. As long as you do your best, the tears from the loser at the checkout are also hot and weighty.

 You know, when winter
  mango still with a tropical climate
  between the articulate, the slightest sweet
  I know, you love-season fruits are even in the winter
  , especially when a person, you will think
  the whole summer was in a mango body insomnia
  dear, find it hard when
  you can actually some of the more decadent
  I love you vulnerable to fatigue and loneliness look
  like a description of listening to birds north Snow