The Solar System

The Solar System[a] consists of the Sun and those celestial objects bound to it by gravity, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The Solar System is also home to two main belts of small bodies. The asteroid belt, which lies between Mars and Jupiter, is similar to the terrestrial planets as it is composed mainly of rock and metal. The Kuiper belt (and its subpopulation, the scattered disc), which lies beyond Neptune's orbit, is composed mostly of ices such as water, ammonia and methane. Within these belts, five

individual objects, Ceres, Pluto, Haumea, Makemake and Eris, are recognised to be large enough to have been rounded by their own gravity, and are thus termed dwarf planets. The hypothetical Oort cloud, which acts as the source for longperiod comets, may also exist at a distance roughly a thousand times beyond these regions. Within the Solar System, various populations of small bodies, such as comets, centaurs and interplanetary dust, freely travel between these regions, while the solar wind, a flow of plasma from the Sun, creates a bubble in the interstellar medium known as the heliosphere, which extends out to the edge of the scattered disc. Six of the planets and three of the dwarf planets are orbited by natural satellites,

usually termed "moons" after Earth's Moon. Each of the outer planets is encircled by planetary rings of dust and other particles. Charles Darwin: Origin of the Species; ang tao'y di bastabastang sumulpot kundi untiunting dumating sa kasalukuyan niyang kalagayan at hitsura; unang nagbigay ng ebidensyang nagpatunay dito; maraming tao ang di naniwala dito dahil labag daw ito sa istorya ni Adan at Eva. Humanap ang mga siyentipiko ng ebidensiya upang mapatunayan ang teorya ni Darwin

Isinasaad ng teorya ito na ang buhay sa daigdig ay nagmula sa simpleng selyula. Mula rito, ang iba't ibang anyo ng buhay (lifeforms) ay nagbago at dumami sa iba't ibang kaparaanan sa paglipas ng panahon. Sa ibang salita, ang mga simpleng organismo ay nagbigay-daan sa pglitaw ng iba't ibng uri ng higit na maslimuot na organismo makaraan ang libo o milyong taon ng pagbabago o ebolusyon.

Halimbawa, ang tAi at ang gorilya ay sinasabi ng mga siyentipiko na nagmula sa iisang ninuno. Isa ngang inaatupang ng mga siyentista ang pagtuklas sa ninunong ito gayundin ang mga pgbabago nto hanggang sa maging modernong tao.