In the daily news, telling about how another private space company launched its first (second, third, and so on) rocket, lucky cargo to the ISS, preparing for the season opening of space tourism, and even makes plans for colonization of the nearest neighboring planets, news from the big government space agencies as they begin to get lost. And yet recall that the space Agency NASA began an extremely ambitious mission to study the Sun.
12 August 2018 with a US air force base at Cape Canaveral in Florida was produced by the launch vehicle Delta IV Heavy. Cargo – sun probe “Parker”, whose task is to overcome the almost 150 million kilometers of space and a rendezvous with the Sun. Parker will have to get close to the star as far as I’ve gotten to him no spacecraft. On the way to the Sun, the probe will carry out several gravity assist around Venus, becoming according to forecasts of NASA will be the fastest man-made object in space. Today let’s talk about 10 most interesting facts related to this mission.
To touch the Sun
Before the Solar probe “Parker” the goal that until then could not fulfill none of the human-made spacecraft. He will study the outer atmosphere of the Sun. The so-called crown. To do this, he’ll get to the star at a distance of 6.2 million kilometers, in fact, “touching” the outer layer of its atmosphere. The unit will deal not only with solving puzzles of the stars, but also will enrich our knowledge about how the Sun affects the magnetosphere of our planet. The importance of this mission can hardly be overestimated, as is becoming more common technology that is somehow affected by the activity of our Luminary. It is possible that this mission will enhance our ability to study the Solar system as a whole.
50 years of training
The launch in August 2018 was the culmination of more than 50 years of development and planning of this space mission. That the temperature of the solar corona can reach a million degrees Celsius, the scientific community has found out in the 40-ies of the last century. Confirmation of the existence of the so-called solar wind (highly charged ionized particles of the plasma emitted by the crown) took place in the 60-ies. However, scientists still can’t understand why the temperature of the corona of the Sun far above the surface temperature of stars. In addition, it is unclear what accelerates the particles of the solar wind. The answers to these questions can be obtained only through direct contact with the solar corona, the researchers said.
The idea to hold such an investigation were first proposed in 1958. Since then, several spacecraft approached the Sun, but none of them were close with the star as much as according to forecasts it should make sun probe “Parker”.
The first spacecraft NASA, named in honor of a living person
Space Agency NASA gave their spacecraft a variety of names, but none of them was named in honor of another living person. Sun probe “Parker” is named after the astrophysicist Eugene Parker in 1958 predicted the existence of the solar wind.
50 years of the Parker led a complicated theory about how the stars give up their energy. He introduced the concept of “solar wind” to describe the cascade emission energy of the Sun and even proposed a theory that explains the reason for the higher temperature of the solar corona in comparison with the surface of the star. In addition, the astrophysicist reviewed the model of the outer atmosphere of the Sun with a constant outflow of matter from the crown and showed that the solar wind velocity increases with distance from the Sun, reaching supersonic values. The scientist also analyzed the influence of the expanding corona at the magnetic field in the solar vicinity and found that the field must be helical due to the rotation of the Sun. His conclusions about the speed of the solar wind and the spiral structure of the solar magnetic field was later confirmed by spacecraft. Now Parker ‘ 91. Despite the age, 12 August, the day of the launch astrophysicist was present at the launch complex.
Solar wind
The principal scientific objectives of the mission will be generally focused around the secrets associated with the solar wind. Created inside of the crown gusts could reach the speed of 1.6 million kilometers per hour. Scientists at NASA hope to find out why the solar corona so hot, and what accelerates the motion of the solar wind. These things are impossible to figure out without being near the source of the mechanisms responsible for these processes.
The Sun is very difficult to get
In fact, for the flight to the Sun is required to 55 times more energy than a mission to Mars. First, the distance from Earth to our star is about 150 million kilometers. But distance is not the only factor, in raising the issue here. The main problem here is the so-called lateral velocity, that is speed relative to the desired motion vector.
For understanding the principle of the lateral velocity you need to understand how bodies move in orbits. In fact, all objects orbiting the Sun endlessly falling toward the star. However, lateral velocity do not allow them to fall because they actually overtake the body, which are falling. The earth moves around the Sun at a speed of 108,000 kilometers per hour. As a result, when the apparatus will descend from an orbit of the Earth, it will move the space forward and will fall into the Sun, but will always miss, because it will remain an indicator of its lateral velocity. In order to get to the star unit, you just need to fall.
To address the issue of the lateral velocity, NASA plans to use gravitational maneuvers around Venus. They will almost completely pay this rate, but will increase the maximum speed of the Solar probe Parker, which at its peak can reach up to 200 kilometers per second.
Gravitational maneuvers around Venus
Possible to get closer to the sun, the Solar probe Parker will have to perform several gravity assist around Venus for 7 years.
After the first flyby of Venus, the probe will be released on an elliptical orbit with a period of 150 days (2/3 of the period of Venus), making 3 turns, when Venus makes 2. After the second flight, the period is reduced to 130 days. Less than 2 revolutions (198 days) spacecraft to meet with Venus for the third time. This will reduce the period to one half of Venus (112.5 days). At the fourth meeting, the company will account for 102 days. Using 237 days, the probe will meet Venus for the fifth time, and the rotation period is reduced to 96 days (3/7 from Venus). The apparatus at this point will do for 7 turns, when Venus will only do 3. The sixth meeting will be held almost two years after the previous one and will reduce the period to 92 days (2/5 from Venus). After another five revolutions around the Sun, the probe will meet up with Venus in the seventh and last time that will minimize the period up to 88-89 days, allowing to come a bit closer to the Sun.
The fastest spacecraft in history
Thanks to the multiple gravitational maneuvers around Venus, the spacecraft will eventually be able to reach speeds of 692 000 kilometers per hour, which is faster than any other space probe built by man.
At this point in time, the fastest a spacecraft is a probe “Juno”, designed to study Jupiter. His current speed is around 266 thousand kilometers per hour. The speed of the spacecraft “Voyager 1”, launched to conquer interstellar space in the late 70-ies and left the Solar system 35 years later, approximately 61,000 kilometers per hour. The maximum speed of the Solar probe Parker more than twice will exceed the rate of “Juno” and 11 times the rate of “Voyager-1”.
The heat shield
The heat shield of the probe is no less impressive than its maximum speed. Size is located in front of the camera sun shield is 2.4 meters in diameter. It is designed to reflect the extreme heat from scientific equipment of the probe. The thickness of the screen is 11.5 cm. It consists of carbon composite foam sandwiched between two carbon plates. The front plate facing the Sun is coated with a special white ceramic coating which helps to reflect heat as efficiently as possible. The materials used are allowed to make the shield pretty easy. It weighs only 73 kg.
In space the temperature can be thousands of degrees, but no specific object to be heated, since the temperature is determined by the speed of the particle motion, then heat is measured as the total amount of energy that they carry. Particles can move quickly (high temperature), but if low, then energy will be a bit (a little heat). In the space of little particles, so few of them able to transmit energy to the apparatus.
The Autonomous spacecraft
One explanation of the efficiency of the thermal screen is very “smart” software, which is controlled by the spacecraft. When the probe will be in the Sun sort of connection between him and the Earth will be unilaterally interrupted every 8 minutes. During this time the probe will be able in just 10 seconds to make the necessary adjustments.
The creators of the probe made software absolutely all possible scenarios of development of events, which only can imagine, so the unit is able to change the angle and rotation of the protective screen if required.
Researcher of project Solar probe Parker Nicola Fox calls this device “the most Autonomous spacecraft created by man”.
Unique cargo
In March of this year, NASA invited the public to participate in the action in which the names of hundreds of thousands of participants will be placed on a plaque and sent to the Sun together with the probe. One of the participants was William Shatner, the actor who played captain Kirk in the epic “Star trek”. In total, the request to add his name on the plaque NASA sent more than 1.1 million people.
“This is perhaps one of the most ambitious and extreme intelligence missions in the history of mankind. In addition, the spacecraft will carry with me as many names of people as you support this mission,” said research fellow Nicola Fox.
10 facts about the new ambitious NASA mission to the Sun
Nikolai Khizhnyak