Mount St. Helen has a reputation for being the most active and the most deadly volcano in the U.S.

Fifty-seven people were killed and 250 homes were destroyed when she last erupted on May, 18, 1980.

NASA scientists hope to avoid a similar scenario by having access to real time information about threatening seismic activity that precedes an eruption.

To achieve that goal they have placed spider-like sensor pods inside the volcano itself. 

Fifteen sensors were lowered by helicopter into the mouth of Mount St. Helens – a place too hot and dangerous for humans to operate in.

[Steve Chien, NASA Jet Propulsion Laboratory Scientist]:
"These sensors are smart enough to know when these things are happening, to know when it's actually some type of earthquake or minor tremor as opposed to the wind blowing the trees around or rocks falling. That enables the sensors to change how they are set up, to collect different types of data and that enables us to get better data on the volcano."

To create the near real-time data stream, the sensors form a virtual wireless network, communicating with each other and the Earth Observing-1 (EO-1) satellite, in NASA's Goddard Space Flight Center.

[Sharon Kedar, Geophysicist, Nasa's Jet Propulsion Laboratories]:
"In the context of volcano monitoring we want to have the best educated guess to make decisions that will save lives and properties."

Mount St. Helens is a proving ground for the spider sensors.

[Steve Chien, NASA Jet Propulsion Laboratory Scientist]:
"Some day we would like to deploy sensors very similar to this to Mars and that would enable us to study all types of interesting events on Mars. Atmospheric events, such as dust storms or sort of mini-tornadoes or to study the freezing and thawing of the Martian ice cap. And also to study Mars quakes, there is a lot of interest in understanding if, you know, Mars is seismically active.”

Future U.S. manned space missions are under a veil of uncertainty because of costs.

So, it’s quite likely these spider sensors will make it to Mars before humans do.