There are several regions on Earth where mean annual temperatures are well below freezing and yet liquid water persists. Such polar regions provide excellent analogs to study the hydrological cycle […]
Methane (CH4) is an important greenhouse gas in the Earth’s atmosphere, accounting for approximately 20% of the observed greenhouse effect. With an atmospheric lifetime of about ten years, methane levels […]
The current mean temperature on the equator of Mars is a blustery 69 degrees below zero Fahrenheit. Scientists have long thought that the Red Planet was once temperate enough for […]
![An artist’s depiction of our world when the Earthshine measurements were taken, enhanced to show the “red edge” from vegetation. A distant astronomer on another planet would see the spectral signatures of our oxygen atmosphere, water, and chlorophyll from land plants. [enlarge] Credit: John Walker’s “Earth Viewer,” Christine Lafon, (Harvard-Smithsonian Center for Astrophysics).](https://i0.wp.com/astrobiology.com/wp-content/uploads/2002/10/Astronomers-Find-Life-on-Earth.png?resize=1200%2C719&ssl=1)
Now that the discovery of extrasolar planets, or planets around distant stars, has become relatively routine, scientists are now tackling the next step: finding life-bearing worlds. To do this, observers […]
In less than a week, our collective understanding of the amount of water on Mars has been totally revamped. First there was the announcement that liquid water is apparently at […]
On the same day that NASA was announcing the apparent presence of liquid water near the surface of Mars, another research team announced that Mars once had salty oceans like […]
The eddy diffusion coefficient is estimated as a function of altitude, separately for the Jovian troposphere and mesosphere. Complex organic molecules produced by the Ly alpha photolysis of methane may […]
The 1975-1976 Viking Mars Mission is described in detail, from launch phase through landing and communications relay phase.
