Revolutionary calculations carried out
The asteroid 6489 Golevka was on 10. May 1991 Discovered at Mount Palomar by Eleanor Helin. The name of this asteroid is reminiscent of the multinational radar observations in June 1995. The 70-M Goldstone antenna sends out the radio pulses and the radar echos are received by the Russian 70-M antenna in Evpatoria and the Japanese 30-M antenna in Kashima. Therefore, the name Goldstone Evpatoria-Kashima.
On the example of the approximately 500-meter gross stone brocken, it has become possible in May of this year to confirm the Yarkovsky effect. For the asteroid had previously passed the earth in profit, namely in 1991, 1995 and 1999 and will no longer be so close to the career of the earth in our generation. Steven R.Chesley from the Jet Proulsion Laboratory and employees of three other bodies have dedicated themselves to science of this task and thus a presentation of David Vokrouhlicky under modified Doppler examinations from Puerto Rico and California realized.
The asteroid 6489 Golevka.
Basically, it’s about a model in which the Yarkovsky effect is described by a number of physical parameters. In addition, the revolution time, the surface conductivity and the surface density pay. This in turn is dependent on the intensity of the backposting force and the room density, wherein the latter is determined exclusively by the mass of the asteroid.
Radar probe residuen from the Golevka quantities (Residuen are the difference between the measured position and computerized forecast).
For asteroids such considerations are the first of their kind. They will draw more and have the way to determine the physical circumstances of each NEA. Nea as "Near Earth Asteroids" be interpreted when the asteroids approached the sun as 195 million kilometers.
6489 Golevka can manage the earth up to 13 times the moon removal and is classified as a potentially dangerous object. In addition, he ares as an earth train cruiser to the family of Apollo Asteroids. Many small asteroids are trumberhes, which are held together by gravity, but 6489 Golevka seems to be a struggled, massive boulders. By 2046, the last chance is to judge its orbit near the earth.
Golevka in the game of the solar system
The Yarkovsky effect, from the Russian-Polish researcher I.O.Yarkovsky made for the first time 100 years ago, science has made considerably richer. Basically, it is a situation that is one of our world: a day-night rhythm of asteroids. For example, the afternoon of an asteroid is warm than his morning because the sunlight long has fallen on him. Or the morning side rotates more slowly than the warm afternoon side. The episode is an asymmetric weak rocket engine. Thus, the spin, the movement of the asteroids as the engine works: Safe when the spin moves away from the sun, easy, D.H. Slower as soon as the movement leads to the sun.
The fact that this results from different course shows, for example, the works Asteroid Families – Long-Term Dynamical Evolution due to Chaotic Diffusion and Yarkovsky Effect. They demonstrate a tremendous diversity, namely day and years of dependencies. There are also changes to the coarse half-axis and YORP processes (The Recent Breakup of Asteroid in the Main-Belt region (Nature 417, 720-771 (13 Jun 2002)). This is called: Instead of a rule-right course, the activity of the asteroids is changed a bit each time.
This again explains that over the years, the circulation of the body is suddenly brought into a gravitational level. The asteroids come into resonance and are sometimes included in the internal solar system. Or they fall oler than so far suspected of the earth. Nevertheless, such course shows that the long-term prognosis of asteroids and the long-term prediction for dangerous collisions with the earth in the emptiness.
For example, Giorgini and his colleagues (Science 296: 132-136 (2002)) involve the known factors, such as the prere of solar radiation and the gravitational effect in their calculation. However, how close the asteroid will come from the earth, this results from the non-well-known physical data: coarse, shape, mass, revolution speed and the way you reflect light and warm in space.
Scientific support of these observations Joseph Spitale supplied from the University of Arizona in Tucson (Science 296: 77 (2002)). For this purpose, Josef Spitale develops a complicated model with which the railway of a sky corporation is described – taking into account the Yarkovsky effect. In his calculations, the researcher has reviewed to what extent has a change of these properties to the train of the three asteroids 6489 Golevka (500 meters in diameter), 1566 icarus (one kilometer diameter) and 1620 geographers (2.5 kilometers diameter). His result: The distraction is coarse enough over decades and works best with the small corps. In this respect, the results of Steven R.Chesley An important assessment. Make it clear that the Yarkowsky effect is much more impact on the asteroids can be made than previously thought.