Shop Windows to the Universe

We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.
This is an image showing a Martian sunset.
JPL/NASA

Mars' Thin Atmosphere

This is image of a Martian sunset illustrates just how thin the Martian atmosphere is.

The terrestrial "blue sky" comes about because molecules of the atmosphere scatter sunlight. In this image, the Martian sky appears pink and a little bit dark at sunset. This is because there are not enough molecules in the atmosphere to scatter the amount of light we are used to seeing on Earth, and also the many rusty-colored dust particles in the atmosphere contribute to the pink color. If you would like to know why the Earth's sky is blue, check the Quickie Question, below.

The thin atmosphere may have something to do with the cold surface temperatures because of the lack of a greenhouse effect, as well as having an affect on the strength of Martian winds.

Shop Windows to the Universe Science Store!

Our online store includes books on science education, ranging from evolution, classroom research, and the need for science and math literacy!

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Mars Global Surveyor Measures Martian Surface Temperatures

This image shows how cold the surface of Mars can be. The temperature data is from the Mars Global Surveyor mission. The scale to the left shows that purple regions are the coldest, about -170 degrees...more

Martian Surface Winds

The surface pressure of Mars is about 1/150th that of the surface pressure of the Earth. This means that there are much fewer molecules in the atmosphere. This means that the atmosphere near the surface...more

Mars Express Orbiter

The European Space Agency (ESA) launched a mission to Mars called "Mars Express" in June of 2003. The Mars Express spacecraft has two parts: an orbiter that will circle Mars for at least one Martian year...more

Martian Volcanoes

On this map of Mars, the lightly cratered Tharsis Ridge is shown, as well as the heavily cratered Martian highlands (near the bottom of the picture), and Valles Marineris to the right. The volcanoes are...more

The Transfer of Water in Martian History

The unusual global geography of Mars helps to explain the fact that water has been drawn from the southern hemisphere to the northern hemisphere of the planet through all of Martian history (that is, from...more

The Martian Cryosphere

The Martian geography is one of high altitudes at high southern latitudes and low altitudes at low latitudes. The ground is less frozen at low latitudes because it is warmer and water can evaporate. Thus,...more

Martian Floods

Separate from the Martian outflow channels, or the river valley networks, are large Martian lakes (600 km, or ~1000 miles across) which exhibit evidence of a periodic and catastrophic release of water...more

Martian Fog

This is an image of fog in a Martian canyon. The presence of fog provides evidence of water, and a water cycle on Mars. More fog has been seen in images returned by Mars Global Surveyor of the south polar...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF