At the end of February last year, many media outlets reported a collision in orbit between American and Russian satellites. The Americans were out of luck, because their satellite was active, but ours was not.
On ORT, information about this event was presented as follows: the satellites moved towards each other and collided at a speed of 8 kilometers per second. This was the first time that satellites collided in orbit. All three of these statements are, to put it mildly, not entirely accurate.
Let's start with a beautiful screen shot of two satellites orbiting towards each other. Since the beginning of the space era, all satellites and spaceships, both ours and the American ones, have always been launched only in the direction of the Earth's rotation in order to use its own linear rotation speed, which reaches 0.5 km / s at the equator. What this gives can be seen in a simple example: our aged but reliable royal "seven", if launched at the equator in the direction of the Earth's rotation, can put into orbit a payload of about 5 tons, against rotation - less than one and a half tons. And why is this necessary? Unless, for the sake of some exotic purpose, which I do not have enough imagination to present.
The only difference is that our northern Plesetsk cosmodrome launches satellites moving at a large angle to the equatorial plane, and the American one at Cape Canaveral - at a much smaller one. However, these angles are determined purely for practical purposes. So the collision most likely just happened on overlapping courses.
But let's return to the option announced by the media that the satellites were moving towards each other and collided at a speed of 8 km / s. Something is not good for our journalists, not only with Russian speech, but also with arithmetic. In this case, the speed of the oncoming collision will be 16 km / s, and with such an impact, a significant part of the mass of both satellites will simply evaporate.
And finally, this case is not the first and not the only one. In the 90s of the last century, several cases of observations by astronomers of similar collisions were published. On August 2, 1983, a meteor patrol in the Novgorod region observed a collision of two objects, presumably artificial earth satellites, which were moving perpendicular to each other. After crossing their trajectories, an explosion occurred. One of the objects, without changing the speed and direction of movement, proceeded along the orbit further, while the other changed its course by 45 degrees to the north and went beyond the horizon.
On July 27, 1992, a group from the Procyon Youth Scientific Astronomical Club was at the astropoligon of the Mining Institute in the Pskov Region. There they conducted curriculum observations of the Cassiopeid meteor shower. They also observed the movement of artificial earth satellites. One of them at 1.23 Moscow time reached the area below the constellation Dolphin, and suddenly for 2 seconds it was lit up with the brightest flash. Such that the light of the stars faded, and shadows fell on the ground. To the surprise of observers, after this outbreak, the satellite did not stop its existence, but only slowly disappeared into the cone of the earth's shadow. After 100 minutes, another satellite was seen flying in the same orbit - this is possible only if both satellites are launched by the same rocket (from myself I will add that it was most likely the same satellite that had time during this time to turn around the Earth. V. P.)
Having reached the area of the outburst, the satellite, having crashed into the cloud of particles remaining after the outburst at great speed, “lit up”, changing its brightness by 5-6 magnitudes. (This message was published on September 21, 1992 in the CHAS PIK newspaper). We can also mention the earlier reports of American and Indian astronomers who observed similar phenomena.
There is another category of emergencies in orbit that could not be observed visually, both due to the cloud cover under the epicenter of the event and due to the lack of visual observations of this area of the sky (recall that 2/3 of the Earth's surface are seas and oceans) …
Looking through the official reports from the day the first artificial earth satellites were launched, it was possible to count about fifteen accidents in orbits, when a normally launched and normally functioning apparatus suddenly suddenly stopped pa6otu. Moreover, among them were satellites with several independent channels of information transmission and independent power supply. Naturally, we are talking only about non-military satellites, the military do not like to advertise their failures. And the sudden cessation of satellite functioning most often indicates a catastrophic collision with an unknown body. Moreover, the likelihood of such collisions is constantly increasing every year. Today, thousands of active and inactive satellites, as well as their fragments, in addition to smaller space debris, revolve around the Earth. And satellites of any purpose that do not require maintaining atmospheric pressure inside them are very vulnerable to any external mechanical impact, as soon as the protective cones that protect them at the active launch site are thrown off.
I would like to remind you of the history of the American lunar modules. The astronauts who returned to Earth later joked that they were made of food foil, and they were afraid to pierce their shell with an inadvertent elbow movement. And besides collisions with space debris in intersecting orbits, an even greater danger exists when colliding with small meteoric bodies, whose speed of invasion into the earth's atmosphere can exceed 40 km / s. Such the smallest pebble will pierce any satellite like an armor-piercing projectile. Even micron-sized particles - the so-called micrometeorites - are dangerous. Already on the first descent spacecraft, plates of various materials were installed to assess the degree of influence on them by micrometeorites, and during a long stay in orbit, these test plates were as if eaten away by microcraters.
Spacecraft bound for the outer planets, especially Mars, are even more dangerous. Adjacent to it, in the space between Mars and Jupiter, is the asteroid belt, which includes planet-like asteroids such as Ceres, Juno and Vesta, as well as billions of smaller debris. During their mutual collision, those that lose their orbital speed, either move to orbits closer to the Sun, primarily the Martian one, or fall on the Sun. In this regard, the Martian orbit is the most dangerous for terrestrial vehicles, which is confirmed by the numerous cases of the termination of their functioning upon reaching Mars or its satellites. Unfortunately, all sorts of anti-meteorite screens and protective fields exist so far only on the pages of science fiction novels.
