ad info

 Headline News brief
 news quiz
 daily almanac

 video archive
 multimedia showcase
 more services

Subscribe to one of our news e-mail lists.
Enter your address:
Get a free e-mail account

 message boards

CNN Websites
 En Español
 Em Português


Networks image
 more networks

 ad info


  sci-tech > space > story pagecorner 

Genesis spacecraft to collect solar wind samples

By Robin Lloyd
CNN Interactive Senior Writer

In this story:

A potato chip trip

Sampling the sun


(CNN) -- A NASA mission that will be the first to return a space sample to Earth since Apollo 17 is expected to bring back particles from a source that sounds far more ephemeral than moon rocks -- the solar wind.

But samples of solar wind, a supersonic tunnel of highly charged gas particles racing away from the sun, can be "collected," just like the wind on Earth, because it is burst of particles as well as a force.

Solar wind is one small variable in the growing field of space weather, which mainly focuses on solar flares -- brief, intense increases in light from the sun. Solar flares can wreak havoc with cell phones, televisions and power grids and pose serious hazards to astronauts or spacecraft.

Mouse over components for text descriptions in this artist's depiction of the Genesis spacecraft   

"Just like for Earth's weather where there are numerous satellites covering the whole globe and studying different things, space weather needs to be studied on a much bigger scale," says Swarthmore College physicist Michael Brown. "You need to look at the sun and the Earth and all of the vast distance in between, so there needs to be lots of satellites and instruments."

Although the $216 million Genesis mission has unique features, Brown's comment is good news for NASA. There already are a number of solar-observing satellites in operation -- most notably the SOHO satellite, designed to study the internal structure of the sun, its outer atmosphere and the origin of the solar wind.

Other solar missions include NASA's TRACE satellite, which studies the sun at a high resolution but cannot see it all at once, as SOHO can.

Also, the International Solar Terrestrial Physics project is an umbrella for 12 different solar-observing satellites. NASA's Ulysses studies the poles of the sun and the solar wind.

From past data, scientists can infer the solar wind's composition, but Genesis will be the first to measure it directly, returning its samples to Earth for analysis. The plan is to measure the abundance of various forms of hydrogen, helium, oxygen and other gases emitted by the sun in hopes of learning about the building blocks of meteors, comets and our solar system.

"The other satellites rely on spectrometers and particle measurements. They are in situ (in position)," says Genesis mission director Chet Sasaki. "We are a sample return mission."

A potato chip trip

After a January 2001 launch, the Genesis spacecraft will journey a million miles sunward -- but only 1 percent of the distance to the sun .

Its path will follow a contorted set of loops, a potato chip-shaped trajectory used by some other solar observing satellites. It eventually will orbit a gravitational balance point between the sun and the Earth before unfolding silicon collectors, where particles will imbed themselves.

After two years of sunbathing, Genesis should return to Earth in 2003. A capsule with the collectors is slated to be rescued by a helicopter from a parafoil plummet over the Utah desert.

Sampling the sun

Most scientists believe the solar system was formed 4.6 billion years ago by the gravitational collapse of the solar nebula, a cloud of interstellar gas, dust and ice created from previous generations of stars.

As time went on most of the gas and dust was pulled together by gravity to form the sun while other grains of ice and dust stuck to one another, eventually forming planets, moons, comets, and asteroids.

By examining the makeup of the solar wind, scientists hope to learn the composition of the solar nebula. The sun itself is too hot to sample at its surface -- more than 3,000 degrees Fahrenheit.

And while it is possible we'll see more lunar landings and lunar samples in coming years, the Genesis mission is designed to make it so no one ever has to sample the sun again, let alone consider the impossible -- landing there.

"This is the periodic table of NASA missions because we are looking at the sun's chemistry for all the missions," says Genesis public outreach director Alice Krueger. "Ours is a terribly basic mission."

Launch of crucial weather satellite postponed
July 14, 1999
Solar scientists: 'S' marks the violent spots
March 9, 1999
New images reveal 'honeycomb' source of solar wind
February 4, 1999

Genesis Mission
SOHO: The Solar and Heliospheric Observatory
Swarthmore College
International Solar Terrestrial Physics (ISTP)
Note: Pages will open in a new browser window
External sites are not endorsed by CNN Interactive.
Enter keyword(s)   go    help

Back to the top   © 2001 Cable News Network. All Rights Reserved.
Terms under which this service is provided to you.
Read our privacy guidelines.