2003 YN107

2003 YN107 is a very small near-Earth asteroid that was discovered on 20 December 2003 by the automatic sky monitoring LINEAR ( Lincoln Near Earth Asteroid Research). The diameter of the asteroid is only about 10 to 30 meters. He is a cruiser Earth's orbit, so it is classified ( according to the eponymous asteroid Aten ) as Aten - type and orbits the sun on one of the earth's orbit very similar, almost circular orbit. Another special feature is that its average orbital period around the Sun is approximately equal to one sidereal year. Its most notable feature is that he 1996-2006 never farther than 0.1 AU (about 15 million kilometers ) away from Earth and that he slowly circled the earth once within a year. 2003 YN107 but was not a second moon of the earth, because he was not tied to it. He is the first known representative of a more long postulated group of co-orbital objects, the quasi-satellite, which have these web properties. Prior to 1996, there was 2003 YN107 in a so-called horseshoe orbit along the Earth's orbit around the sun, which of the asteroid 2002 AA29 was very similar. Also since 2006, he holds back on for some time in such an orbit. Such an orbit change seems to be relatively common in these co-orbital companions since 2002 AA29 is to be a quasi- satellite of the Earth in about 600 years also for some time.

• 6.1 databases

Orbit

Path data

The orbit of 2003 YN107 is a sun distance between 0,974 AE for the perihelion, the point nearest the Sun, and 1,021 for the aphelion AE, the sonnenfernsten point, for the most part within the orbit. The orbits of most asteroids are, however, in the so- called asteroid belt between Mars and Jupiter or further out beyond the orbit of Neptune in the so-called Kuiper belt. By perturbations of the large gas planet, mainly by Jupiter, and by the Yarkovsky effect, ie the path change by unbalanced inputs and emission of infrared radiation, asteroids are deflected into the inner solar system, where their orbits then influenced by other close flybys of the inner planets further be. Distractions of asteroids into the inner solar system by Jupiter and the other planets, however, usually arise orbits with high eccentricity. 2003 YN107 has an eccentricity of 0.021, however, a similarly low value as the earth with 0.0167 and thus has a nearly circular orbit. So it is less likely that he was thrown into the inner solar system from an orbit in the outer solar system by Jupiter or another planet. Because of its small eccentricity is speculated that he always was on a near-Earth path and he or a predecessor body thus created near the Earth's orbit. One possibility would be in this case that he could be a abgesprengtes fragment of the crash of a medium asteroid with the Earth or the moon.

The mean orbital period of 2003 YN107 is a sidereal year. After being deflected into the inner solar system, or was on a path near the Earth's orbit, the asteroid must be advised on a corresponding to the Earth orbit. On this track, he was always distracted from the earth so that its own orbital period, the orbital period of the Earth around the sun accessible. At its current orbit so he will always be kept from the Earth in sync with their own circulation.

Due to its lightweight orbital inclination of 4.3 ° to the ecliptic ( the orbital plane of the Earth), however, his course is not with the earth congruent, but slightly inclined to the earth.

Web form

Looking at the Earth's orbit with nearly congruent orbit from 2003 YN107 from around the sun moved along with the earth's motion from the reference system, one finds that he - almost like a second moon - slowly revolves round the earth; for a round he needs but one year. Its slow orbit around the earth in one year is caused by its slightly different eccentricity. The radial component of motion is directly caused by the difference of the eccentricities between the Earth and 2003 YN107, while the component of motion along the Earth's orbit is caused by the slightly different speed at perihelion and aphelion. At perihelion it overtakes the earth from the inside while the outside falls back at aphelion further in relation to the earth. In the course of a year it is a complete orbit around the Earth. Since he is not like the moon tightly bound to the earth, but mainly under the gravitational influence of the sun, called this body quasi-satellite. This is analogous to two cars side by side drive with the same speed and overtake mutually, but are not tied to each other about. See also the chart alongside the future orbit of the asteroid 2002 AA29, which is similar to the 2003 YN107. 2003 YN107 was since 1996 a quasi- satellite of the Earth and remained so until 2006. However, due to the gravitation of the earth, he meets after one revolution around the Earth is not exactly back at the starting point at, but describes open loops around the Earth. So he came to the Earth on 21 December 2003 with 0.0149 AE ( 2.23 million kilometers ) very close, which is less than 6 times corresponds to the Earth-Moon distance.

After 2006, he left the vicinity of the Earth and orbits the sun on a so-called horseshoe orbit along the Earth's orbit, where it precedes the Earth along its orbit. The name horseshoe orbit becomes clear when one considers the co-moving with the Earth reference system from only the relative movement of 2003 YN107. He describes it along the orbit a large arc of 360 °, which is shaped like a horseshoe. When moving along the Earth's orbit, he spirals around this, which he needs for a spiral rotation one year. This spiral movement in the co-moving with the Earth reference system comes about through his slightly different from the Earth's orbital eccentricity and orbital inclination, the difference in the orbital inclination for the vertical and one of eccentricity for the horizontal component of the projected spiral motion is responsible.

Achieved in the year 2066 2003 YN107 back the earth on the other hand from behind her comes down to about 0.026 AU ( 3.9 million km ) near. He gets back under its gravitational influence and is further elevated to a slower orbit slightly away from the sun. Wherein it can no longer keep up with the speed of the earth well, until it reaches it again in 2120 from the beginning. In this re- encounter with the Earth in 2003 YN107 is her come, however, very close and very distracted by it. Most likely 2003 will YN107 then captured by the earth and a real second moon of the earth. The calculations will be messy, so that you can say anything precise about the time after 2120.

If we calculate the orbit of 2003 YN107 backward in time, one finds that he was staying before 1996 also in a horseshoe orbit, the period was 133 years for a full forward and back swinging. This horseshoe orbit can be calculated back to the year 1750. 1750, there was a chaotic transition between quasi-satellite orbit and horseshoe orbit, so that one can say nothing more on the period before 1750.

Physical Properties

About 2003 YN107 is out of its orbit very little known. But from its small absolute brightness of 26.2 to 26.7 and a suspected albedo ( reflectivity ) of 0.04 to 0.20, it is concluded that he has only about 10-30 m in diameter and thus is a very small asteroid. Only because of its very Earth-like track suspects you, that he might be a abgesprengtes piece of earth or moon, which was in a collision with an average asteroid.

View

Due to its very Earth-like orbit of the asteroid for space probes is relatively easy to reach. 2003 YN107 would be a suitable object of study for closer examination of the structure and composition of asteroids and the temporal evolution of their orbits around the sun. Due to its small size and therefore almost completely missing attraction structure and composition of this celestial body but are unlikely to be determinable by country emissions.

Because of its perigee can be followed very closely the path of 2003 YN107 using radar astronomy and measured. This can be predicted Yarkovsky effect, which leads to a slight change in track and was recently confirmed at the asteroid Golevka, after a relatively short time notice of a few years and check detail.