40 years ago, Earth scientists sent two interplanetary stations, which were named Voyager 1 and Voyager 2, on a long flight. These stations are identical, only the name and launch time distinguish them.
Voyager-2 station was launched on August 20, 1977, her twin on September 5 of the same year. Before the fortieth anniversary of the Voyager 1, it remained to wait a couple more weeks. There is no confusion with the numbering of probes, since specialists originally planned that Voyager 1 should outrun its colleague. And it turned out: the probe with the number one could break forward between the orbit of Mars and the asteroid belt.
Both stations went on different routes, which allowed them to go down in history. "Voyager 1" at the moment is the most remote object from our planet, created by man. And Voyager 2 is the first and only so far probe that was able to pay a visit to four of the planets-gas giants of the Solar system: Jupiter, Saturn, Uranus and Neptune.
Voyager 1 is not only the most man-made object from the Earth, but also the fastest. Its speed is 17 km / s. Now it is at a distance of 139 astronomical units, this is 21 billion kilometers. The flight data of both Voyagers is constantly updated on a special page of the NASA Jet Propulsion Laboratory.
Boundaries of the Solar System
They say that Voyager 1 left the boundaries of the solar system. This happened more than once. Scientists several times announced that the probe "has already precisely" left our system, after which it turned out that this is still not the case.
The comic book xkcd joked over the difficulty in determining space records. The number of times that Voyager 1 left the boundaries of the solar system, xkcd: 1189
The borders were groped in 2012. At this time, the apparatus entered the heliopause zone, where the pressure of the solar wind balances the pressure of the interstellar medium. The heliosphere itself is a region of near-solar space where the solar wind still predominates over the "galactic wind" – the stream of particles of the interstellar medium.
In 2013, it was reported several times that Voyager 1 went beyond the limits of the influence of the Sun, And in September of the same year, confirmation was received.
Thus, the probe nevertheless found itself in interstellar space. Finally, the scientists were convinced of this only in 2014. Now the plasma that surrounds the probe is about 40 times denser than it was within the solar system.
It should be noted that scientists, speaking of the fact that the apparatus left the system, speak about the heliosphere. If we talk about going beyond the limits of the orbit of celestial bodies that revolve around the Sun, this has not happened yet. The probe has not yet reached the orbit of Sedna, the trans-neptun object, not to mention the Oort cloud. This cloud, "populated" by long-period comets, is considered the outer edge of the solar system.
Set of speed
In order for the vehicles to gain sufficient speed, they were launched with the help of a heavy Titan 3E with an additional fourth stage. The first and second stages were filled with nitrogen tetraoxide and aerosol. Liquid hydrogen and oxygen were used in the third stage, and solid fuel was already used in the fourth stage.
Features of the probes
Scientists have taken into account that a few years after the launch, the Voyagers do not have enough solar panels to operate all systems. Therefore, each of the vehicles is equipped with three radioisotope thermoelectric generators, the power of which at the time of launch was 470 watts. Now, because of half-life, the power is already lower – about 300 watts. Over time, it will fall. It is believed that in a few years the energy received by the probes will not be enough for normal operation, so that the systems will continue the path in radio silence.
The design of the devices also provides for the presence of three types of computers. The first serves to control scientific instruments and instruments, the second – manages flights, the third – the command. Two workstations have been installed to back up each type of computer.
Work on the creation of the Voyager continues (July 9, 1976), NASA
40 years ago, designers who developed probes wanted to communicate with alien minds. The authors of the project laid the news from the Earthlings to the vehicles.
The main thing that the scientists wanted to indicate in the message is the location of the Earth. This was done by creating a specific map, where the main reference points are pulsars. In total there are fourteen, and each has unique characteristics. An alien civilization that can intercept the "Voyager" (any of them) about the features of pulsars should be known. Each of them exists for millions of years, so this is a fairly reliable lighthouse, which will work for a very long time. The alien mind can understand where the Earth is and in a million years. Perhaps some pulsars can exist for several billion years. All of them quickly rotate, plus they have a unique "profile" of pulses of electromagnetic radiation. The delay between the pulses is also unique. As a result, the pulsars were considered to be "cosmic beacons", and to draw a map based on pulsars.
The length of the lines that connect each pulsar to the Sun (this is the central element on the map) shows how far each of them is from our star. The speed of rotation of the pulsars is written in binary code, so that all data was reduced to only 12 characters. In addition to the location of the Earth, the map is capable of giving an understanding of when the probe was launched.
The information in question was recorded on gold plates. The author of the map is Frank Drake. His daughter, Katherine Denning, said that scientists during the preparation of the map and making gold plates did not really argue about the possible risks of contact with "brothers in mind". Now, by the way, Denning is studying the pros and cons of sending messages to extraterrestrial civilizations. What is characteristic, now more and more specialists, not to mention ordinary people, believe that it is not worth trying to be heard – it is better, as before, to simply listen to the space in search of "relatives".
"Voyagers" – a threat to the Earth?
As mentioned above, more and more people are now inclined to think that "Voyagers" are a threat to humanity, as they carry information about the exact location of the Earth. These data can be used by extraterrestrial intelligence, for example, to attack our planet.
Why did the scientists decide to send the map and the gold plate, where the most detailed description of life on Earth and humanity? Francis Drake says that when the Voyagers were launched, scientists did not even know if other planets exist outside the solar system. More precisely, most experts believed that, of course, they exist. But there was no evidence of this.
Now, thanks to the Kepler telescope, scientists already know that exoplanets are the rule for the universe, and not an exception, and there are many earth-like planets. In the end, it may well be that life in space is also a rule, and not an exception.
But since we do not even know what could be "beyond the cosmos," sending any data about ourselves can be an extremely rash act. "In those years, almost all the people I talked with were optimists who believed that if aliens exist, they are probably friendly," Drake said recently. "No one thought that what we do can be simply dangerous."
Nevertheless, the same Drake believes that the likelihood that the cards on board probes will get to an extraterrestrial civilization is extremely small. "They are moving at a speed of more than 10 kilometers per second. At this speed, the devices will be able to reach the nearest star in only half a million years, then another half a million will be needed in order to arrive at another star. And it is clear that they are not directed to a particular light. They just fly to where they were sent. "
If extraterrestrials find the Earth, the scientist thinks, then by radio noise and other signs of existence on the planet of civilization. But probes are likely to fly in the silence of the Universe forever, remaining unnoticed for millions of years.
While the devices continue to operate, which means that they are still sending valuable information to the Earth about what the distant space is.
So "Voyagers" are still good, not evil. They have brought tremendous benefits, and the harm of the message of humanity is hardly possible.