Michael D. Lemonick
Far beyond the Kuiper Belt lies the hypothetical Oort Cloud, a spherical shell of icy objects believed to surround the solar system at distances up to100,000 AU. Though we've never directly observed it, the Oort Cloud is thought to be the source of long-period comets that take thousands o...
Even though there are only 8 official planets in the solar system, it can be tricky to remember them all in order from the Sun. A popular technique to use a mnemonic, which can be any sentence you want using the first letter of each planet. The letters for each word in the sentence ...
Although water ice has been commonly found in Kuiper belt objects and comets in the Solar System4, no definitive evidence for water ice in debris disks has been obtained to date1. Here we report the discovery of water ice in the HD 181327 debris disk using the near-infrared spectrograph on...
The main asteroid belt betweenMarsand Jupiter also divides our solar system into the inner and outer solar system. Here's a bit about each of the eightplanets, in orderof their distance from the sun. Terrestrial Planets The inner solar system consists of four rocky planets: Mercury, Venus, ...
A选项,比较对象正确，remnants of the Solar System's formation是插入语，修饰small bodies，正确，但句...
According to traditional ideas about the formation of the Solar System starting from a protoplanetary disk of gas and dust, a well-defined distribution of planets and minor bodies is expected: (a) volatile-poor rocky bodies (terrestrial planets and asteroids) in the inner part of the Solar Syst...
Ceres is the closest dwarf planet to Earth. All of the otherdwarf planets in the solar systemare very far away, in theKuiper BeltbeyondNeptune. Ceres has some similarities with the other dwarf planets, such as Pluto and Eris. It is rubble left over from theformation of the solar system—...
It is perhaps easy now to look at a diagram of the solar system as it is firmly understood and see where Copernicus – who even managed to place all of the six planets known in his pre-telescope time in their proper order from closest to the sun to farthest away, including Earth – ...
Compared to the major planets in the Solar System, small icy bodies have experienced much less thermal evolution and their physical properties are well preserved. The Kuiper Belt objects (KBOs) are numerous small icy bodies beyond Neptune, which are thought to be the most primitive remnants from...