{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Atmosphere - escape speed gas molecules can escape from...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Atmosphere From space Earth looks blue: from : 1. scattered light in atmosphere 2. reflected light from oceans Light scattering: molecules and dust in atmosphere scatter light which colors scatter best depends on particle size in our atmosphere, size is right to scatter blue best   sky is blue setting sun looks red Atmosphere Composition   78  % Nitrogen (N 2 ) from decay of biological stuff and volcanic eruptions 21  % oxygen (O 2 ) from photosynthesis in plants (CO 2  -> O 2 ) 1 % everything  else   if no life on Earth => very different atmosphere Ancient atmosphere had more hydrogen (which escaped), methane and amonia Composition depends on: 1. original formation of planet - what gasses were trapped 2. chemical processes (including life) 3. escape speeds of different molecules
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: escape speed: gas molecules can escape from planet if travelling fast enough Air molecules are always in motion speed depends on temperature and mass of molecules hotter => faster => easier to escape lighter => faster => easier to escape If a planet's atmosphere is hot enough, light elements will escape Earth is hot enough for hydrogen and helium to escape Atmosphere and temperature atmosphere absorbs energy from sunlight X-rays and ultraviolet radiation are absorbed at different altitudes average surface temperature is about 300 K if no atmosphere, would be about 270 K (below freezing) This temperature difference comes from the "greenhouse effect" atmosphere traps heat near Earth's surface...
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern