P1:对于冥王星的分类有争议,但自从发现以来它就是一个星球。海王星之外还有很多小的星体围绕太阳旋转。这些星体都存在于Kuiper Belt上。
P2:传统的KBO远离海王星,使其可在太阳系存活。他们的轨道也有较小的偏心率。一些传统KBO轨道倾角足够高,表明他们曾被某种方式激活。
P3:分散的KBO有偏心率较大的轨道。过于靠近海王星使得他们可以被完全送出太阳系。 第三种KBO:海王星绕太阳公转三次时,它绕太阳公转两次。
KBO orbit the sun twice during the time it takes Neptune to orbit three times. 这些物质被称为Plutinos小冥王星
P4:Kuiper Belt已经缩小了,海王星的壮大导致撞击,KBO化为灰烬。然而一些甚至比冥王星还大的五支可能会在70AU(日地距离)外发现。
179. KBO
P1: We know that there are some controversies regarding the classification of Pluto. Less well known is the existence of at least 70000 other small bodies orbiting the sun beyong Neptune. Those objects are known as the Kuiper belt.
P2: Classic Kuiper Belt Objects(KBO) orbit far from Neptune, allowing them to survive for the age of the solar system. They also have relatively small eccentricities in their orbits.
P2: Scattered KBOs have large, eccentric orbits. The scattering effect can sometimes send them out of solar system entirely, where they may end up orbiting in the Oort Could or becoming a short-period comet into planet-crossing orbits. The third category of KBOs orbit the sun twice during the time it takes Neptune to orbit three times.
P3: The Kuiper belt was larger than now. The development of Neptune causes collisions that turned many KBOs to be blown into interstellar space by solar wind. However some objects larger than Pluto may be found beyond 70 Astronomical units.
Author's opinion: There are more things we don't know yet about the Kuiper belt. Introduced three types of KBOs and pointed out there are probably bigger objects further away.
Mainpoint:describe a comprehensive KBOs orbitp1-use the controversy Pluto to draw off the KBO
p2-the location of the KBO, the criteria which can excite the KBOs
p3-the scattered effect and the influence of the Neptune
p4-the development of Neptune caused collistions to make the KBOS become smaller
1. 相当大的一部分公众知道对于冥王星的分类存在一些争议,尽管自从它被发现以来,官方角度一直是一颗行星。很少被人知道的是至少存在7000个其他的小天体在Neptune外围绕着太阳旋转。这些小天体,大部分形成于太阳系的吸阶积阶段,主要被发现在一个叫做Kuiper Belt的环中。
2. 经典KBO的轨道远离Neptune, 让他们可以在太阳系的年龄段存活。他们的轨道也有一些相对小的偏心度,尽管一些经典KBOs的倾斜角高到足够大,意味着他们可以被刺激过,可能被一些星体,也可能被一个经过的行星,或者可能被一些仍然未知的方式。这些经过的行星假说要求一颗行星从太阳上去经过100AU的天文单位,一个罕见的事件,尽管当然可能,如果我们的太阳和其他行星一起形成。(一个AU=平均地球到太阳的距离)
3. 分散的KBOs拥有大的偏心的轨道。他们偶尔接近海王星的散射效应可以把他们从完整的太阳系统中发射出来,在那里他们可能会结束轨道运行在Oort云里。海王星的影响同样也将这些星体送进行星交错的轨道,在那里这些星体被作为短期彗星分类。在第三种类的KBOs环绕太阳两次在海王星环绕太阳三次的时间里。Pluto也是这样,这些星体被称作Plutinos(这也导致了一个语义上面的难题,因为冥王星复合冥王星的定义,然而它的意思是“小冥王星”)
4. KPOs belt 实际上比它之前更小,海王星的发展引起了撞击,让很多KBOs变成灰尘被太阳风吹进星际空间中。但是,一些星体,甚至大于Pluto, 可能被发现仍然超过70AUs
accretional phrase of solar system: 太阳系的吸积阶段
eccentricities-古怪的
eccentric orbits-偏心轨道
cluster-团
semantic conundrum-语义难题
KBOs in a third category orbit the sun twice during the time it takes Neptune to orbit three times.第三类KBO在海王星绕太阳运行三次期间绕太阳运行两次