Basic explanation:[observation; observe; monitor] Observe and measure
He spent more than 30 years observing the days, months andplanetThe movement of——《Copernicus》
1. It often refers to the observation or measurement of natural phenomena.
2. Observe and measure.
3. Observe and measure (the situation).
Citation explanation:
Observe the measurement.
Xu ChiGoldbach Guess - Geological Light:geological structure The line is close to the observation site, serious, and there is nothing careless. "[1]
Cosmic observation
Announce
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Footprints on the Moon
(1) In the vast space, the moon is the nearest neighbor of the earth.Although it is a close neighbor, it is 380000 kilometers away from the earth, which is really beyond our reach.
(2) However, in July 1969, American astronauts Armstrong, Collins and Aldrin finally visited the moon on behalf of all mankind, marking an important step in human exploration of space and a new milestone in the aerospace industry.
(3) On July 16 of that yearKennedy Space Center"Saturn 5" rocket stands like a giant with its head held high and its tip pointing straight into the blue sky, more than 100 meters high.It will drive“Apollo 11”The spaceship went into space.The ground service personnel have filled up its three-stage fuel tank with fuel, kerosene in the first stage rocket, and liquid oxygen and liquid hydrogen in the second and third stages.
(4) Armstrong, the commander of the spacecraft, Collins, the pilot of the command module, and Aldrin, the pilot of the lunar module, had breakfast in the canteen of the space center and put on their spacesuits.A great moment is coming, and they will embark on the journey of exploring the moon.They said goodbye to the people who came to see them off.This will be the farthest journey that mankind has ever taken.They walked under the launcher, took the elevator, came to the command cabin, and entered the narrow command cabin.
(5) The ground crew checked the rocket very carefully and proved that everything was normal.After the command center sends out the ignition command, the computer starts to work automatically.automaticIgnition deviceThe igniter was lit, and the "Saturn 5" began to make a rumbling sound. The earth shook violently, and the rocket rose slowly and accelerated.The three astronauts lay in the cabin and watched the readings of various instruments.At this time, they are under great pressure, which is caused by the acceleration of the rocket.At 2:42 seconds after launch, the first stage rocket automatically fell off, and the second, third and second stage rockets continued to rise.When reaching an altitude of 182 kilometers, the second stage rocket automatically dropped off, reaching a speed of 6.8 kilometers per second.9 minutes and 5 seconds off the ground, level 3rocket engineStart the work, and the spacecraft will enter the predetermined orbit at the predetermined time and altitude.At this point“Apollo 11”The altitude of the spaceship is 2650 kilometers, and the speed is 7.67 kilometers per second.
(6) After the spacecraft enters the predetermined orbit, it will first fly around the earth to observe whether it is normal and whether it can fly to the moon.According to the measurement of flight conditions, the Houston Ground Command Center issued an order to march to the moon.Then, the third stage rocket was launched again, reaching a speed of 10.5 kilometers per second, entering the lunar landing orbit and running towards the moon.
(7) The three astronauts had dinner in the cabin and began to sleep peacefully 13 hours and 30 minutes after the launch.The ground station stopped giving orders to them so as not to interfere with their dreams.They must have a good rest, because they cannot successfully fly to the moon without good physical strength and energy.
(8) The spaceship moves slowly in space like a lonely boat.It flew over the middle point of the distance between the moon and the earth, and at 8:33 p.m. on the 19th, it flew over the neutral point of the moon and the earth's gravity.The static point of this gravity is 28000 kilometers away from the moon, and the moon and the earth are gravitationally balanced at this distance.The beautiful moon can be seen from the spaceship.It emits beautiful silver light and hangs quietly above the spaceship.
(9) At 9:32 p.m. on the 19th, the ground command center sent a call.The three men got up in a hurry.On this day, they should land on the moon as planned.The spaceship began to slow down, and before long, they would reach the sky above the moon, which had long been their dream.The three astronauts worked nervously. They held the joystick in case the computer failed, they could operate it manually.Fortunately, the computer sends normal instructions. When the spacecraft slows down to a certain speed, it automatically gives the command of ceasing fire.Armstrong and Aldrin transferred to the lunar module and talked to the ground command center.Soon, the lunar module broke away from the spaceship, and the spaceship continued to fly in the orbit of the moon, while the lunar module began to land, constantly descending slowly in the elliptical orbit.
(10) The lunar module landed smoothly on the moon.The astronauts who landed on the moon excitedly reported to the Houston Ground Center that they had successfully landed.The Houston Ground Center is also pleased to congratulate them on their success.
(11) At 11:39 a.m. on the 21st, the door of the lunar module was opened.At 11:51, Armstrong walked down the stairs and landed on the moon.The surface of the moon is full of tiny particles, a bit like the beach of the earth.Then Aldrin came to the moon.This is a great moment.This is a great step for mankind.The exact time of this moment is 11:56:20 on July 21, 1969.This is a milestone in human exploration of space.
(12) As soon as they reached the surface of the moon, Armstrong and Aldrin began their intense work.They have many tasks, but the oxygen supply for their breathing is very limited, only enough to use for four hours.Therefore, we must grasp every minute and every second.They checked the landing condition of the lunar lander and found that everything was normal;They took out shovels and collected samples of lunar soil and rocks;They took out a monument from the lunar module and erected it on the moon.The memorial tablet is engraved with the images of the eastern and western hemispheres of the earth, and it is also engraved with: in July 1969, the planet of the solar system - the earth's first human footprint on the moon.On behalf of all mankind, we come here for a peaceful journey.
(13) Then Aldrin took out the TV camera from the lunar module and installed it on the surface of the moon;They also installed a solar wind measuring device to detect cosmic rays;A laser instrument is also installed to accurately measure the distance between the moon and the earth;A lunar seismometer was installed to measure the lunar shock.They took out the American Star Spangled Banner and planted it on the moon with a solemn look.After the completion of these tasks, they breathed a sigh of relief and made the first communication between the moon and the earth with President Nixon of the United States.The President warmly congratulated them on their success in landing on the moon.
(14) Three hours passed quickly, and only enough oxygen for one hour was left in their oxygen bags.The Houston Ground Center ordered them to stop operations and return to the lunar module from the moon.They carefully boarded the lunar module, took off their lunar suits, put on their spacesuits, had a beautiful lunch and slept sweetly for seven or eight hours.
(15) At 0:15 on July 22, 1969, the Houston Ground Center woke up Collins in the spaceship and the two astronauts on the lunar module, ordered the lunar module to rise to a certain orbit around the moon, and“Apollo 11”Spacecraft docking.The lunar module engine started, and it kept rising, accelerating, and entering the scheduled orbit.At 6:35 a.m. on the 22nd, it successfully docked with the Apollo 11 spacecraft waiting there.The three astronauts met over the moon. They shook hands tightly in the narrow command module excitedly.The lunar module has completed its historical mission. It is uneconomical to bring it back to the earth.As a result, it was thrown into space.
(16) The spaceship began to return to the distant earth.At 1:35:8 on the 25th, it entered the Earth's atmosphere at an appropriate angle.When descending to a height of 4000 meters, three large parachutes opened in the air“Apollo 11”The spaceship splashed down in the predetermined sea area and was rescued by the navy waiting there.
(17) Man set foot on the moon for the first time.The great expedition went back and forth a total of 760000 kilometers and lasted 195 hours. The three astronauts completed an expedition to another planet together.
(18) Shortly after returning from the moon landing, that is, on September 16, 1969, the three astronauts went to the United States Capitol and delivered a speech at the joint session of Congress to talk about their feelings on the moon landing.
(19) Armstrong talked about the significance of landing on the moon.He commented on their "small step" to leave the lunar module and step on the moon: "This small step is a small step for one person and a huge leap for the whole human race."
