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The Winter 2010 issue of The Earth Scientist includes a variety of educational resources, ranging from astronomy to glaciers. Check out the other publications and classroom materials in our online store.

The Size of the Planet Matters


(medium sized)

(very large)

Hydrogen (H) less than 1 hour days over the age of the Universe
Helium (He) roughly 1 day 100 times the age of the solar system over the age of the Universe
Oxygen (O) 800 million years over the age of the Universe over the age of the Universe

This table shows the time it takes, on average, for a few common atmospheric gases to escape the gravity of a planet. The table shows that as the planets get larger (more massive), it is harder for the gases to escape. The table shows that the average time for any gas to escape from Jupiter's gravity is much too long. The same is true for all the Giant planets. Therefore it is likely that all the gases in Uranus' atmosphere are probably the original gases swept up by the proto-Uranus.

Return to atmosphere

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Uranus' Atmospheric Hazes

Besides methane, Uranus' atmosphere contains more sophisticated atmospheric molecules such as ethane gas, acetylene, and diacetylene. All these molecules form layers of haze at different altitudes high...more

Uranus' Mesosphere

The mesosphere of Uranus is a region of balance between warming and cooling. That essentially means that nothing happens there. Except for diffusion, the atmosphere is still. Upper reaches of the atmosphere,...more

An Overview of Uranus' Atmospheric Structure

As on Earth, the atmosphere of Uranus consists of a troposphere, stratosphere, mesosphere, and thermosphere. The troposphere is the region where the visible clouds are to be found. The stratosphere, as...more

Altitude Variations of the Belts & Zones

On Uranus, as on Jupiter, the winds in the belts and zones blow first in one direction, then in the opposite direction. Wind blows east in a belt, and west in a zone. The clouds rise up in a belt, and...more

Why Uranus looks like a "bullseye"

The striped cloud bands on Uranus, like Jupiter, are divided into belts and zones. On Uranus the belts and zones are hard to distinquish. The left picture shows the north pole of Uranus. In this picture...more

Uranus Clouds, Overview

The clouds of Uranus, composed of methane crystals, are found very low in the troposphere, and are difficult to distinquish below the smog haz es of the planet's atmosphere. False color is used, in the...more

A Uranus summer = a Uranus day

In this picture, the view of the north poles of the Earth and Uranus are shown together. In the view of the Earth, the sun is shining from the left, and part of the north pole is in daylight and part of...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA