Silicates are minerals that contain silicon atoms bonded to oxygen atoms. The basic building block for all silicate minerals is called a tetrahedron, where one silicon atom is bonded to 4 oxygen atoms (Figure 3.6). Silicate minerals also often contain other elements, such as calcium, iron, and magnesium.hosphates have a tetrahedron building block that is similar to that of the silicates. But, instead of silicon, phosphates have an atom of phosphorus, arsenic, or vanadium bonded to oxygen. Although there are many minerals in this group, most of the minerals are rare.
Neptune is the coldest planet in the Solar System. At the top of its clouds, temperatures on Neptune can dip down to 51.7 Kelvin, or -221.4 degrees Celsius. Thatâs cold! Pluto gets colder, but then, Pluto isnât a planet any more.
Neptune is so far from the sun that high noon on the big blue planet would seem like dim twilight to us. The warm light we see here on our home planet is roughly 900 times as bright as sunlight on Neptune. Long Time Did you know that one year on Neptune is equal to about 165 Earth years? This fact makes Neptune the planet with the longest year. 165 Earth years is a long time, especially when we consider that the planet in second place for this title (Uranus) takes only about 84 Earth years to complete its year. The Invisible World Want to go outside and view the planets without a telescope? You can, but you won't see Neptune.