At around 6 p.m. on January 14, 2024, there were witnesses of the "UFO incident" in several provinces and cities in northern China, including Beijing. Everyone saw several hazy light clusters flying together, without a sound, flying and flying away, and in the process, some people took images of light spots suddenly brightening and bursting out of a large aperture.
Image taken from a video that went viral on Weibo
What is this? Is it aliens coming to Earth? Or is it some weapon from another country?
What is Rocket Cloud?
Let's talk about the conclusion first, in fact, these strange halos are not aliens descending on the earth, but the traces left by earthlings when they send things into space with rockets, they are called "rocket clouds".
The rocket needs to be burned in the sky, and the narrow and straight tail flame of the rocket when it first takes off, in space, the high-temperature propellant ejected or discarded by the rocket will rapidly expand in all directions in a vacuum and weightless environment, and "blow" into several "big balloons" without shells. The hazy spots of light that you see this time are actually the rays reflected by the sunlight shining on these "big balloons".
Some netizens may ask, this is winter, the sun will go down at six o'clock? That's right, it is already night on the ground at this time, but the rocket has flown to a considerable height, so the sunlight can still illuminate the propellant, and it has become a few light clusters we see.
Is it related to weapons?
Many netizens have expressed their opinions on this rocket cloud, in addition to UFOs, some netizens think that this may be some kind of weapon or reconnaissance equipment, because some videos show that the blurry light point has suddenly lit up, and it looks like it is controlled by a person, so is this the case?
This time, although the rocket cloud has nothing to do with weapons, it really comes from a foreign country. If we check the recent launch records, we will know that at 4:59 p.m. Beijing time on January 14, SpaceX's Falcon 9 rocket was launched from California, USA. The rocket will send 22 Starlink satellites into orbit, with the mission code SL-7-10. 53 minutes after launch (5:52 p.m. Beijing time), the second-stage rocket was turned on for the second time, and the position where the rocket swept at this time happened to be seen by the people in North China. And the light point that everyone saw suddenly brightened and burst out of a large aperture, which is that we witnessed the second start of the second-stage rocket.
At this point, we not only know the principle of this phenomenon, but also find out which launch caused this phenomenon, and this UFO (Unknown Flying Object) has completely become a KFO (Known Flying Object).
As for many netizens, they also reported that there was no sound in the whole process, which was very weird, which was actually because the position of the rocket was already very high, and the atmosphere was so thin that the sound could not be transmitted. And these points of light flew and disappeared because it gradually entered the shadows of the earth.
Sometimes, the rocket cloud will have fun tricks, but because the rocket launch itself is a simple trajectory, it is often not a good thing to play too much. This spiral-shaped rocket cloud, such as the one that appeared in Norway on the night of December 8, 2009, was caused by a failed test launch of an intercontinental missile by Russia. Sometimes, when the first and second stages of a normal rocket are separated, the first stage of the rocket will also cause this kind of scene while spinning and falling.
Why aren't rocket clouds common?
There may be netizens who love to think about it and question: You see, there are more and more rocket launches on the earth, why are rocket cloud incidents still very rare?
From the previous analysis, it can be seen that to see this rocket cloud, several conditions are required:
1. The rocket should fly over the ground to witness it. Don't be fooled by the word "space" and think that it is an area that can be seen by the whole earth. In fact, most of the rocket launches are low-earth orbit missions, which are only one or two hundred kilometers above the ground, and the sighting range is only a circular area of about 2,000 kilometers in diameter, accounting for only about 1% of the total area of the earth.
2. The timing of the sighting of the rocket cloud is often the evening or dawn of the sighting ground, where the ground is night and the sky is day. Otherwise, the rocket cloud will either be submerged in the sky light or enter the shadow of the earth, neither of which we can see.
3. Weather is also very important, and it was the clear skies in North China this winter that allowed everyone to witness this spectacle. And the icing on the cake is that on the night of January 14, the moon walked to Saturn's side, and many astronomy enthusiasts saw rocket clouds by the way while admiring Saturn's accompaniment to the moon. Of course, there are also unlucky friends who are so focused on watching Saturn that they miss the rocket cloud......
来自EasyNight的微博
It can be inferred that since it often takes dozens of minutes for a rocket to go into space from launch, which is enough for the rocket to go around the other side of the earth, it is not easy for us to see a halo and flash rocket cloud like this time if we launch it domestically, and those countries on the opposite side have a good chance, just like North China saw SpaceX's rocket cloud this time.
But we often see another rocket cloud produced by our own rocket, which is the remnants of a first-stage rocket that has just been launched, like the one shown below. It is obliquely inserted into space from the lower atmosphere, blown by the wind in the atmosphere, and illuminated by the sunlight at high altitude, which is really beautiful, for example, a certain Taiyuan Satellite Launch Center carried out a launch mission, and such a beautiful rocket cloud appeared.
The picture is taken from CCTV News, and the source is shown in the copy
Finally, to sum up, just as many UFOs are actually optical phenomena caused by human activities, this rocket cloud is just a small scenery left in space when humans explore space.
Source: "Popular Science China" WeChat public account