Late last week, I got an assignment to write about water on Mars for Scholastic News 4.
Mars is a fun planet. It has tickled people's imaginations for centuries.
Why? Some people believe it's because Mars is visible to the naked eye. The theory goes that ancient people felt that this red dot wandering around a background of stable stars was a bad omen. But in reality, five planets can be seen with the naked eye -- Mercury, Venus, Mars, Saturn, and Jupiter. Joe Rao describes the phenomenon on space.com. So there must be something else at work here.
One old school Web site that I like "Astronomy Answers" probably gets it right when it says that Mars fascinates humans because it is the planet most like Earth. Like Earth, Mars boasts an atmosphere, wind, clouds, large volcanoes, ice capped poles, seasons -- and water.
Maybe we just like Mars because it's one of our closest neighbors.
Reports from the Phoenix Probe
The presence of water on Mars has been expected since the Odysssey spacecraft took photographs of what looked like water ice near the Martian equator in 2002.
The presence of water ice was confirmed on August 1, 2008 when the Phoenix probe scoped up a sample of soil and gently heated it to 32 degrees F to release water vapor. William V. Boynton, the lead scientist for the instrument that detected the water, rather poetically said they "tasted" the water.
Here's a report on the discovery from the Voice of America.
The New York Times reports on discovery of ice.
The probe also discovered sodium, potassium, magnesium, fluorides - things that we find in our own bodies and that are important for life. Still, no evidence of life has been discovered.
Space Today Online features a nice historical overview of human exploration of Mars.
This backgrounder from NASA provides a timeline of our knowledge of water on Mars.