Can I go live on the moon? With today's technology, it's not that difficult to live stream the moon landing. Now, NASA has conducted a laser communication space test, successfully transmitted a 4K video clip to the International Space Station through a laser, and successfully transmitted it back.
In this test, NASA staff installed portable laser terminals on an aircraft, which then transmitted data to a ground center in Cleveland, where the ground network transmitted the data to the NASA test facility in New Mexico, and then to the Laser Communications Relay Demonstration (LCRD) satellite at an altitude of about 35,000 kilometers, which relayed the data to the ILLUMA-T terminal on the International Space Station.
Now that the United States is conducting laser communication tests, is it because the United States does not have the ability to transmit these video clips to the International Space Station? In fact, no, before that, NASA used radio waves for ground-to-air communication, but the efficiency of radio wave data transmission is not as good as that of laser communication technology. Studies have shown that laser communication technology uses infrared light to transmit data, and the transmission speed is 10-100 times faster than radio waves, and the efficiency is significantly higher.
The success of this laser communication test shows that NASA is expected to achieve a live broadcast of the spacecraft landing on the moon in the subsequent Artemis manned return program to the moon, and this technology will also pave the way for us to explore Mars or explore the more distant universe in the future.
Chang'e-6 moon landing picture stuck?
Previously, when the Chang'e-6 probe landed on the far side of the moon, it collected precious samples from the far side of the moon, and then took off from the far side of the moon with precious lunar samples and returned to Earth.
This is the first time in human history that we have successfully brought back samples from the far side of the moon, so the success of the Chang'e-6 probe has created many firsts for mankind, for example, this is the world's first spacecraft to complete the sampling mission on the far side of the moon, and the continent has also become the first country in the world to successfully bring back samples from the far side of the moon. It has very important significance and value.
At that time, when the Chang'e-6 lander and ascender assembly landed on the moon, the whole process was very complicated, because the far side of the moon was always facing away from the earth, and it was impossible to directly communicate with the probe on the far side of the moon, and it was necessary to complete this series of operations with the help of the Queqiao-2 relay satellite.
During the lunar landing, the lander and ascender assembly relied on its own engines to power deceleration, first reducing the relative speed with the moon to about 30 meters per second, and the probe assembly was still about 2.5 kilometers from the lunar surface.
At this time, the probe will use the optical imaging sensor carried to image the pre-selected landing area, that is, to carry out rough obstacle avoidance and select a relatively safe landing site first. If there is a large obstacle at the landing site, the probe will adjust it according to the actual situation.
When the probe assembly descends to almost 100 meters, the speed is getting slower and slower, at this time it will hover, and then use the laser sensor to observe the specific terrain of the landing site, and after choosing a suitable landing site, the probe will continue to descend in altitude and finally land steadily on the surface of the moon.
In the process of landing on the moon, the camera carried by the probe captured the footage of the lunar landing process, and from the footage sent back, the picture did not seem to be very smooth and a little stuck. At that time, many netizens said that the current technology is no longer comparable to the Apollo moon landing, why did the live broadcast of the moon landing look smooth when the United States carried out a manned moon landing in the late 60s?
In fact, during the entire Apollo manned lunar landing program, the United States only carried out live broadcasts when the Apollo 11 spacecraft landed on the moon, of course, the technology at that time was not advanced, so the live broadcast picture at that time was also very poor.
In the process of landing the subsequent Apollo lunar spacecraft on the moon, the picture is not only clearer, but also smoother. Of course, the footage of several spacecraft landing on the moon behind the Apollo 12 spacecraft was not live, but the video was filmed during the moon landing and then played back on Earth.
When the Chang'e-6 probe landed on the moon, the picture was a little stuck, which is actually reasonable. After all, the landing site of the Chang'e-6 probe is located on the far side of the moon, and we cannot directly communicate with the probe, so we need to complete it with the support of the Queqiao-2 relay satellite.
Therefore, the instructions sent from the Earth or the signals sent back from the probe need to be relayed through the Queqiao-2 relay satellite, not directly transmitted back to the Earth. Even if the picture is not very smooth, this does not affect the Chang'e-6 probe to successfully bring back precious samples from the far side of the moon.