Re: 80 Chinese Academy of Sciences beauty research bully: there is only one way to crack the Big Dipper.
no time to see the video, the following is the speech version:
the other day I went to a classmate's home, and their little girl asked me, "Auntie, how can I let my Dad see my mobile location information?" What? If I remove my cell phone card, can my mobile phone be positioned? "
here, I can tell you clearly that after taking off the mobile card, the mobile phone can still be positioned. This is because we all know that the location of our mobile phone is satellite navigation system, which has nothing to do with our mobile phone system.
satellite navigation system, it is a group of twenty thousand kilometers of our stars, they do not shine or heat, even the naked eye can not observe them, for us to provide location services. The satellite navigation system is called GNSS system for short. There are 4 VIP members in the GNSS club. Besides the known American GPS system, it includes the Russian GLONASS system, the Galileo system of the EU and the Beidou satellite navigation and positioning system built by our country.
Beidou satellite navigation and positioning system is a satellite navigation and positioning system built by our country. It is now in the stage of construction and application. It is composed of five stationary orbit satellites and 30 non stationary orbit satellites. The Beidou satellite navigation system is expected to provide a global service around 2020. .
in the GNSS club, what are the members' most concerned about? The problem of frequency resources that you are most concerned about. Frequency resource is a kind of international public resource, frequency resource is not you want to buy, want to buy can buy, all frequency resources should apply to ITU, by ITU. Like our freeway, every system has its own lanes, otherwise it will crash.
in the initial stage of the construction of satellite navigation system, the frequency resources are relatively abundant, and the conflict of the frequency resources does not exist in the construction of the relatively early GPS system and the GLONASS system. When the Beidou system and Galileo system were established, the frequency competition was very obvious. The Galileo system was actually applying for the frequency of the resource in advance, but it was known that later Europe had an economic crisis, so the Galileo system was broken, and they had launched the satellite, occupying the track, but did not send the number of the frequency. According to the international electricity Federation (ITU) "first to first come", which country can first launch the satellite up, and the satellite launches the signal of this frequency, and then the frequency resource is yours.
in this case, the April 17, 2007 is the deadline of the frequency resources declared by the dipper, so the Beidou test star must be launched in advance, which is very rare in the history of China's space.
usually satellite launches are delayed only without advance, because a series of problems will arise in advance. But after the coordination of various departments, in order to compete for the frequency, in April 14th, the rocket had been successfully launched at the launch center. In April 14th, at 4 a.m. and 07 in the morning, a new problem was found in the scene. A rocket connector did not fall off according to the rules. If the problem could not be solved within three minutes, it would be a disaster for rockets, satellites and even the launch site.
the launch commander dropped 7 instructions in one minute, 4 points 07 points, and at 4:11 the rocket carried our dipper star to a successful lift. In April 14th, the dipper star was launched, the satellite was changed in April 15th, and the satellite began to send down the signal in April 16th. In the 24 hours before the failure of the frequency resources of the Beidou application in April 17th, China officially opened the frequency resources of the Beidou declaration, and also opened the curtain of the Beidou global system construction.
What do you like to do in a stormy night and thunder and lightning? I like watching horror films better than myself. Lightning and horror film are more compatible. So, what is the difference between thunder and lightning? Yes, it's the satellite launch. When the satellite launches, the rocket body is filled with fuel, and a little spark can cause the explosion of the arrow body. In 1987, the US Hercules rocket was launched in heavy rain. It rose to the sky for a minute and was hit by lightning in the air.
, therefore, when the lightning is usually encountered, the satellite launch will be delayed. But in July 2011, when the ninth Beidou satellites were launched, it was also a thundering weather, but it was waiting for the launch. Why did the mountain know that the tiger was moving towards the tiger mountain?
this is because the Beidou system is not a single satellite, but a constellation. For the constellation constellation, every satellite must have a fixed position. The Beidou system requires not only the orbit to which the satellite will be launched, but also the location of the satellite in orbit. To meet such conditions, there must be a launch window, and this day is a rare launch window. If you miss the chance of the day, it is possible to postpone four months or even delay a year to usher in a new window.
the Beidou system is in full swing in the process of construction. If the launch is postponed, the process will be delayed and the economic loss is immeasurable. The command system at that time decided to launch in the rain, and it was issued in the gap between the two thunderbolts. Luckily, the ninth Beidou satellites were lifted. At the end of the year, the dipper began to try. Now, the Beidou system has launched 22 satellites, which has been able to provide very stable navigation and location services for China and our surrounding areas.