Monday, January 16, 2006

Pluto and Plutonium

In 17 hours, NASA's probe to the planet Pluto, the New Horizons mission, will begin its seven-year journey to the Solar System's ninth planet. At the far reaches of the solar system, there is too little sunlight for solar panels to make electricity, so the New Horizons probe is powered by 24 pounds of plutonium.

Needless to say, placing 24 pounds of radioactive material on a rocket is not done without some controversy. The claim is that dangerous radioactive material could be spread across a large area if the rocket explodes during liftoff, endangering large numbers of people.

Personally, I am confident that the launch will proceed safely and that there is little danger of radioactive release even if the rocket explodes. There is a phenomenal amount of engineering and study that goes into the design and launch of a space probe, and the amount of work increases dramatically when environmental and public safety is an issue. Given the potential risks and repercussions of a poorly-engineered launch, I feel that NASA has studied the issue.

However, I do not dismiss these protesters out of hand. They have a valid point. Radioactive material has been released from spacecraft. One of the most famous examples is the Soviet Cosmos 954 satellite, which crashed into Canada in 1978. As we explore space, we must not become careless, as two shuttle disasters have shown. Putting a heavy chunk of metal into space takes a LOT of energy (rocket fuel), and if quality control is not maintained, there can be disasterous consequences.


  1. From the CNN article:

    If there was an accident during an early phase of the launch, the maximum mean radiation dose received by an individual within 62 miles of the launch site would be about 80 percent of the amount each U.S. resident receives annually from natural background radiation, according to NASA's environmental impact statement.

    Here's my questions:

    "Natural background radiation"? What the heck is that? That sounds kind of scary.

    And why is it that the most powerful news network on earth apparently hasn't heard of the conditional "were"? "If there was an accident"? Ow! It makes my eyes water just to look at it.

  2. We all are constantly bombarded with radiation, from tiny amounts of radioactive elements in rocks to rays from outer space. Nothing to worry about; life has learned to live with it. :)

    Also, CNN is notorious for bad astronomy reporting. Now we can add grammar to the list of complaints.