Comet Churyumov-Gerasimenko: trajectory, dimensions, photo

Comet 67P / Churyumova-Gerasimenko became a frequent guest in the media reports after 2003, when it was decided to send her Rosetta with the Fila module. The goal without exaggeration of the grandiose project was to plant the device on an object and study its characteristics. Today, in April 2015, we can already say that the mission was successfully accomplished. And this was preceded by extensive work on both the creation of a spacecraft and the study of a comet.

Opening

Comet Churyumov-Gerasimenko, trajectory, dimensions and other parameters of it, were well studied even before choosing it as an object of the Rosetta mission. The day of the discovery of this cosmic body is October 23, 1969. The first photographs of Comet Churyumov-Gerasimenko, however, were obtained a little earlier, on the 11th. Then future pioneers Svetlana Gerasimenko and Klim Churyumov, as part of the group of astronomers of Kiev State University, watched the movement of comets in the sky over the surroundings of Alma-Ata.

On 11 October Svetlana Gerasimenko took a picture of comet Komas-Sol, on which there was a strange speck, presumably, the marriage of a photographic plate. However, after a while, already Klim Churyumov, studying this and other pictures from this section of the sky, found that the speck is present at all and visibly shifts against the background of the stars. The photographs were sent to Cambridge by Bryan Marsden, who calculated the orbit of the new comet. They named it after the discoverers. In scientific publications, the cosmic body is designated as comet 67P / Churyumov-Gerasimenko.

Flight Characteristics

As it turned out, the open cosmic body is a short-period comet. This does not make it unique: in the solar system there are more than one hundred objects of the same type as comet Churyumov-Gerasimenko. The trajectory of its flight is such that the perihelion of the orbit (the place of the shortest distance to the Sun) is located between the orbits of Mars and the Earth, and the aphelion (the place of the greatest distance to the Sun) is beyond the orbit of the gas giant Jupiter. The circulation period is slightly less than 6.6 years.

Neighborhood with such a large planet, like Jupiter, does not pass for nothing. The comet Churyumov-Gerasimenko is no exception. The trajectory of her flight was constantly exposed to the gravity of the giant. According to scientists some time ago, one revolution of this cosmic body around the Sun took about three years more, but 10 years before its discovery, the comet has become too close to Jupiter. The result was a reduction in the period of rotation.

Mission Object

If you go back to the Rosetta probe, the 67P comet has become the project's goal for several reasons:

• 40 years have passed since the discovery, during which the object was constantly monitored: astronomers are well aware of its orbit and can foresee practically any possible influences on it;
• The orbit of the comet is deviated from the plane of the ecliptic by only 7 °, which means that there is no need for an additional energy resource to lift the spacecraft above the ecliptic.

Nevertheless, Comet Churyumov-Gerasimenko, whose size, orbit and other characteristics are excellent for such a mission, was not the first candidate. Initially, the probe had to go to the comet Virtanen, similar in its parameters with the 67P. The situation changed due to the failure of the engine of the Arion-5 launch vehicle. The planned start had to be postponed, and the favorable launch moment was missed. At that moment, it turned out that in about a year it would be possible to send Rosetta to another object - the comet Churyumov-Gerasimenko.

Long 10 years

The Rosetta probe had to go to the tail of the comet, having equalized its speed, becoming its companion, determining the possible landing site and dropping the module of the "Fila" on it. For all this to happen, the apparatus had to circumnavigate the solar system for 10 years. During her trip, Rosetta photographed Mars and Earth in several angles, repeatedly crossed the asteroid belt and met two of its representatives, also photographing them. In addition, during the rapprochement, "Rosetta" took pictures of the comet Churyumov-Gerasimenko, who helped clarify its shape. It turned out that 67P is visually divided into two parts, connected by a fairly narrow isthmus. In the articles on 67P, one can find mention of a rubber duckling, on which the comet Churyumov-Gerasimenko resembles. Dimensions of the "head", smaller part, 2.5 × 2.5 × 2.0 km, "trunk" - 4.1 × 3.2 × 1.3 km.

mission Possible

If we do not go into details, we can say that the first landing of the spacecraft on the surface of the comet was successful overall. Module "Phil" landed not exactly where it was planned, and soon exhausted the energy reserves, but was able to convey to Earth a lot of information.

Comet Churyumov-Gerasimenko, photo of the surface of which "Filas" transmitted while in the process of landing, very much "suffered" from the apparatus: it was taped, drilled, shone through, and so on. The researchers obtained data on the composition, relief, gravity. This information is also valuable because the comet has the same age as the solar system, and therefore can reveal some secrets of its formation.

Briefly about the results

Comet Churyumov-Gerasimenko, whose landscape photo helped to draw a map of the surface, was divided into zones according to the features of the relief. Among the formations resembling rocks and dunes, three-meter hills, often found on the entire surface, were discovered. Presumably they are characteristic of other comets.

During the study, it was found that the density of the comet's substance is half that of the water. Also scientists managed to establish the ratio of organic compounds and water molecules. The first was more, which is different from the assumption of researchers. These data forced us to reconsider the hypothesis about the origin of the comet: it was believed that it was formed in the vicinity of Jupiter. The new data convincingly testify that the comet arrived from the more remote part of the Solar system, from the Kuiper belt.

Comet Churyumov-Gerasimenko, the trajectory and features of which came up for the grandiose project "Rosetta", has not yet revealed all its secrets. The device that delivered the "Phil", still accompanies it and still transmits data. Therefore, it is quite possible that in a short time we will learn about 67P much new.