第一百日（1）作屎的老貓（第2/8頁）

不過現在這條規定已經作廢。

唐躍想去哪拉屎，就去哪拉屎。

兩人把所有的糞便都帶進了車庫，這種搗屎的活肯定不能在主站內幹，否則昆侖站還住不住人了。

唐躍把幹燥糞便倒在車庫地板上，隨意清點了一下，發現他這三個月以來，排便還算均勻順暢，這裏所有的大便都是他自己的，再往前其他人的糞便和垃圾都已經被獵戶座一號帶走了。

老貓蹲下來，手中捏著一根不知道哪兒找來的棍子，饒有趣味地戳了戳地板上包裝好的大便，“唐躍，我覺得你可能嚴重便秘且大便幹燥，你看你拉的翔硬得跟大理石似的。”

唐躍戴上口罩，並不想搭理老貓這個話癆。

老貓還在戳地上的大便，翻過來覆過去地戳。

“唐躍你看，這坨翔像不像一顆真空包裝的茶葉蛋？你是怎麽拉出這麽圓的屎蛋蛋來的？能不能演示一下？”

“還有這個，這坨翔大，我估計一下，起碼得有五兩重吧……”

“這坨很有藝術氣息，看上去像是梵高的星空。”

“哎唐躍！你來看這個，這坨翔長得很像你誒！簡直就是一個模子裏刻出來的，你們真是一對父子……”

唐躍惱怒地抄起一塊幹燥的大便砸了過去。

對火星軌道變化問題的最後解釋

作者君在作品相關中其實已經解釋過這個問題。

不過仍然有人質疑——“你說得太含糊了”，“火星軌道的變化比你想象要大得多！”

那好吧，既然作者君的簡單解釋不夠有力，那咱們就看看嚴肅的東西，反正這本書寫到現在，嚷嚷著本書BUG一大堆，用初高中物理在書中挑刺的人也不少。

以下是文章內容：

Long-term integrations and stability of planetary orbits in our Solar system

Abstract

We present the results of very long-term numerical integrations of planetary orbital motions over 109 -yr time-spans including all nine planets. A quick inspection of our numerical data shows that the planetary motion， at least in our simple dynamical model， seems to be quite stable even over this very long time-span. A closer look at the lowest-frequency oscillations using a low-pass filter shows us the potentially diffusive character of terrestrial planetary motion， especially that of Mercury. The behaviour of the eccentricity of Mercury in our integrations is qualitatively similar to the results from Jacques Laskar's secular perturbation theory (e.g. emax～ 0.35 over ～± 4 Gyr). However， there are no apparent secular increases of eccentricity or inclination in any orbital elements of the planets， which may be revealed by still longer-term numerical integrations. We have also performed a couple of trial integrations including motions of the outer five planets over the duration of ± 5 × 1010 yr. The result indicates that the three major resonances in the Neptune–Pluto system have been maintained over the 1011-yr time-span.

1 Introduction

1.1Definition of the problem

The question of the stability of our Solar system has been debated over several hundred years， since the era of Newton. The problem has attracted many famous mathematicians over the years and has played a central role in the development of non-linear dynamics and chaos theory. However， we do not yet have a definite answer to the question of whether our Solar system is stable or not. This is partly a result of the fact that the definition of the term ‘stability’ is vague when it is used in relation to the problem of planetary motion in the Solar system. Actually it is not easy to give a clear， rigorous and physically meaningful definition of the stability of our Solar system.

Among many definitions of stability， here we adopt the Hill definition (Gladman 1993): actually this is not a definition of stability， but of instability. We define a system as becoming unstable when a close encounter occurs somewhere in the system， starting from a certain initial configuration (Chambers， Wetherill & Boss 1996; Ito & Tanikawa 1999). A system is defined as experiencing a close encounter when two bodies approach one another within an area of the larger Hill radius. Otherwise the system is defined as being stable. Henceforward we state that our planetary system is dynamically stable if no close encounter happens during the age of our Solar system， about ±5 Gyr. Incidentally， this definition may be replaced by one in which an occurrence of any orbital crossing between either of a pair of planets takes place. This is because we know from experience that an orbital crossing is very likely to lead to a close encounter in planetary and protoplanetary systems (Yoshinaga， Kokubo & Makino 1999). Of course this statement cannot be simply applied to systems with stable orbital resonances such as the Neptune–Pluto system.

1.2Previous studies and aims of this research