Much of the universe's water may be produced as a byproduct of star formation. When stars are born, their birth is accompanied by a strong outward wind of gas and dust. When this outflow of material eventually impacts the surrounding gas, the shock waves that are created compress and heat the gas. The water observed is quickly produced in this warm dense gas.
Water has been detected in interstellar clouds within our galaxy, the Milky Way. It is believed that water exists in abundance in other galaxies too, because its components, hydrogen and oxygen, are among the most abundant elements in the universe. Interstellar clouds eventually condense into solar nebulae and solar systems, such as ours.
Water vapor is present on:
- Mercury - 3.4% in the atmosphere, and large amounts of water in Mercury's exosphere
- Venus - 0.002% in the atmosphere
- Earth - trace in the atmosphere (varies with climate)
- Mars - 0.03% in the atmosphere
- Jupiter - 0.0004% in the atmosphere
- Saturn - in ices only
- Enceladus (moon of Saturn) - 91% in the atmosphere
- exoplanets known as HD 189733 b and HD 209458 b.
No comments:
Post a Comment