Nuclear-Powered Probe Begins Its 2 Billion-Mile Journey

The largest, most expensive, and most controversial interplanetary probe in the history of NASA blasted off yesterday without a hitch.

The mammoth Titan IVB rocket carrying the Cassini spacecraft rocketed through clouds into a moonlit sky well before dawn, and scientists and engineers embraced when Cassini shot out of Earth orbit 40 minutes after liftoff. The first phase of a seven-year, 2 billion-mile journey was now over.

Although the spacecraft's final destination is Saturn, it will go around Venus twice and Earth once for a gravitational acceleration before heading to the ringed planet.

Now that the probe has made it into space without any problems, it is this Earth flyby - which will bring Cassini within 500 miles of Earth in 1999 - that has Cassini opponents worried. With 72 pounds of plutonium aboard Cassini - the most ever flown in space - antinuclear activists fear that if things go wrong the plutonium could be released into Earth's atmosphere.

But there is a less than 1 in a million chance that the probe would reenter Earth's atmosphere and spread plutonium, says the Energy Department's Beverly Cook. The plutonium is needed to power Cassini.

Its $3.4 billion mission won't begin, scientifically, until the spacecraft reaches Saturn in 2004. If all goes well, the two-story robotic explorer will be the first probe to orbit Saturn, doing so 74 times from July 1, 2004 through 2008.

Cassini also will release a probe to land on frigid Titan, Saturn's largest moon and the second-largest moon in the solar system. Scientists say its cold, preserved state could provide clues as to how life evolved on Earth.

You've read  of  free articles. Subscribe to continue.
QR Code to Nuclear-Powered Probe Begins Its 2 Billion-Mile Journey
Read this article in
https://www.csmonitor.com/1997/1016/101697.us.us.6.html
QR Code to Subscription page
Start your subscription today
https://www.csmonitor.com/subscribe