Astronomy/the atmosphere

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Expert: Jesse Martinez - 5/5/2010


Question
Which layer of the atmosphere do astronauts go through when they make the transition into space?

Answer
The last layer they go through is called the Thermosphere. Here is a complete description of all the layers that a spacecraft launched from the Earth's surface would travel through on its journey into outer space:

1.)Troposphere
Four fifth's of the Earth's atmosphere, (80%) is in the first six miles above sea level. As a land launched spacecraft starts its journey into outer space, it passes through the the majority of the atmosphere in less than a minute before it crosses into the stratosphere.

2.)Stratosphere
This is the area where commercial jets fly. It extends much further up than the typical 35,000 ft the jets fly in all the way to 160,000 feet or 30 miles. 19.9 % of the atmosphere is in this layer, leaving only a measly 0.1% for the rest of the atmosphere.

3.)Mesosphere
It is the coldest place in the atmosphere. The density of the atmosphere is very low. I think it is because the next layer up absorbs a lot of the energy. Also something strange happens when the atmosphere gets thin. The temperature plummets until a certain point, where the Thermosphere begins.

4.)Thermosphere. The conductive and convection properties of gasses change when the air pressure drops to very, very low pressures. Here the temperatures could rise into the 1000 degree or higher category

After that is outer space, sometimes called the exosphere. The exact point at which this transition happens is not firmly defined. It is somewhere between 80 and 150 miles or more, depending on what particles you consider part of the atmosphere.

Here is a site with more information.
http://members.tripod.com/atmosphere_guys/index.html

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Jesse Martinez

Expertise

General and specific questions about the solar system and stellar and galactic astronomy, are what I can easily answer off the top of my head. For example, what is the largest planet in the solar system? How far away is the moon? Have there been any confirmed planets in orbit around stars other than the sun? How many stars are there? The tougher ones like explaining the big bang theory and black holes I will leave to the PhD’s. Even though I could muster an answer, I would have to research it more than I would like. I would also like to answer questions that involve Astronomy with other sciences, chemistry, biology, physics, geology and mathematics as long as they are not PhD level.

Experience

I have been into astronomy since I was 8 years old. I have kept detailed journals of my observations through small telescopes. Over the years I have participated in amateur observation projects for organizations like ALPO. My personal research has involved "discovering" the moons of Jupiter with a 4½-inch Newtonian reflector without any outside information like charts and tables. In a summer long project, I determined the existence of and plotted the orbits of the four major moons of Jupiter. From these observations, my data on orbital elements was surprisingly accurate (orbital radius and orbital period).

Education/Credentials
80 hours of college credits while studying physics and geophysics. Completed correspondence photography course while in high school. Took two semesters of electronics training at a community college. Studied computers and graduated from a technical school at the turn of the millennium, gaining A+ and Microsoft Certified Professional credentials. Hablo Español. Si quieres preguntar en Español, estoy a su servicio.

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