i need information on " the past atmosphere"
please help me ive look on the internet and havent found anything
sth i found out...
Development of the Atmosphere
A. The past atmosphere:
At the early formation of the Earth, as it emerged from the Solar Nebula as a Proto-planet, it is theorized that the Atm. Was made mostly of Hydrogen and Helium. This early atmosphere was "blown off" by collision with high energy particles of the "solar wind" and the heating of the atmosphere by energy from the sun. This left the early Earth rocky with a thin atmosphere. The outer gas planets are too far away from the sun to be affected in this way.
4 Billion years ago atmosphere made mainly of:
a. Methane (CH4) (each molecule made of 1 Carbon atom and 4 Hydrogen atoms)
b. Ammonia (NH4) (each molecule made of 1 Nitrogen atom and 4 Hydrogen atoms)
c. a little Water (H2O) (each molecule made of 2 Hydrogen atoms and 1 Oxygen atom
This was TRULY NASTY! Very Poisonous! Obviously the air is not poisonous now, What happened?
3.8 Billion years ago Sunlight triggered chemical reaction with the (CH4), (NH4) , and (H2O) which broke the molecules apart into a mix of chemicals (Carbon, Hydrogen, Oxygen, Nitrogen) as well as the original substances.
Hydrogen is VERY low mass, so much of it could not be held by Earth's gravity and drifted off into space
Reactions occurred between the other chemicals in the atmosphere forming other molecules like:
a. Carbon Dioxide (CO2)
b. Ozone (O3)
Formed a thin layer in the upper atmosphere ESSENTIAL for life: OZONE protects the surface from Ultra violet Radiation (UV) from the Sun by absorbing it and changing it from Ultra violet wavelengths to Infrared wavelengths (like heat)
Before the ozone layer formed, the only things that could live on the Earth were microscopic organisms deep in the water. The water protected them from UV. They probably got their energy from chemicals in the water NOT from the sun (called Chemotrophs meaning "Chemical fed ")
After OZONE layer formed organisms could survive closer to the surface of the water because the ozone protected them.
MAJOR BREAKTHROUGH organisms start to use sunlight for energy source (called autotroughs ("fed by self"): PHOTOSYNTHESIS BEGINS!!
With the beginning of photosynthesis the atmosphere begins to change "rapidly"
The reaction for photosynthesis is:
6CO2 + 6H20 ---> C6H12O6 + 6O2
It is like a recipe: Take 6 carbon dioxide molecules, and 6 water molecules and Use the energy in sunlight to run the reaction (not written in the equation). When photosynthesis is done 1 Glucose molecule and 6 Oxygen molecules have been made
This is a Key development in the changing atmosphere: the production of OXYGEN (O2)
Leads to a build up of oxygen in the atmosphere (kind of nice for breathing!)
Before the development of photosynthetic organisms (that make molecular oxygen (O2)) the atmosphere had about 3% oxygen (definitely NOT enough to breath :( )
AFTER they developed the atmosphere changed! NOW the atmosphere has 21% molecular oxygen! (thank goodness! )
I can assist you in finding information on the past atmosphere. The internet can be an extensive resource, so let's try a step-by-step approach:
1. Start by searching for keywords related to your topic, such as "past atmosphere," "Earth's ancient atmosphere," or "evolution of Earth's atmosphere."
2. Check reliable sources like scientific journals, academic websites, or reputable organizations like NASA or NOAA (National Oceanic and Atmospheric Administration). These sources often publish articles and research papers on atmospheric science and Earth's history.
3. Consider narrowing down your search with specific time periods of interest. For example, you could search for "Precambrian atmosphere" or "atmospheric composition during the Paleozoic era."
4. Utilize different search engines and databases to access a wider range of sources. Google Scholar, JSTOR, or PubMed can be helpful resources for academic publications.
5. When reading articles or papers, focus on the methodology, results, and conclusions to gain a deeper understanding of the information presented.
6. Take note of any references or citations within the sources you find, as these can lead you to additional relevant information.
7. If you're having difficulty finding information online, consider visiting your local library where you can access books, journals, and other resources related to Earth's history and atmospheric science.
By following these steps, you should be able to find reliable and accurate information about the past atmosphere.