Asteroid to Make Rare

Visit to Earth's Vicinity

An asteroid named for a Celtic god of war will come as close to Earth this week as it has since 1353.

The space rock known as Toutatis will come within 960,000 miles of Earth tomorrow, relatively close by cosmic standards, Astronomy Magazine said yesterday.

Toutatis poses no danger to Earth. However, if it did hit the planet, it would create a blast with the energy equivalent to 1 million tons of TNT.

Measuring about three miles by 1.5 miles, Toutatis will speed by Earth at 22,000 mph.

This asteroid makes a roughly four-year trip around the sun that swings from just inside Earth's orbit to outside the orbit of Mars.

Tomorrow, Toutatis will be 250 times as bright as it was two months ago, but it will still be only one-sixteenth as bright as the faintest stars visible with unaided eyes.

Blacks Run Higher Risk

Of Fatal Prostate Cancer

U.S. black men ages 65 and older run twice the risk of dying from prostate cancer compared with whites, but they are less likely to have a common blood test to detect the disease, a study said yesterday.

The reason for the low rate of prostate-specific antigen, or PSA, testing is not clear, said the report by the Dana-Farber Cancer Institute in Boston. Nor is it clear whether lack of testing, or something else, is causing the higher death rate.

Education, the choices patients make about their health care or the quality of health care services to which blacks have access all may play a role in the testing problem, the study said.

"The level of racial disparity in the use of PSA screening is quite unsettling," said Timothy Gilligan, a physician who was the report's lead author. "While some physicians question the effectiveness of PSA as a screening test, there is no reason its availability should differ according to a man's race."

The study, in the current edition of the Archives of Internal Medicine, is the latest to document disparities in the care given to minorities. It was based on the health records of more than 67,000 men between 1991 and 1996.

Elephant DNA Is Used

In Ivory Poacher Probe

Using elephant dung and skin samples, researchers said they have made a map of elephant DNA that could help catch ivory poachers.

They are already using the method to track smuggled ivory seized in Singapore in 2002, said the researchers, in the United States and Tanzania.

"We are able to monitor where the ivory is coming from," said Samuel Wasser of the University of Washington in Seattle, who led the study. "With that, coupled with monitoring the movement of ivory through ivory markets, we will be able to tell where poaching is most heavily concentrated and improve law enforcement."

Writing in this week's issue of the Proceedings of the National Academy of Sciences, Wasser and colleagues said the key was the ability to sample elephant scat.

The Singapore seizure was tracked to Zambia, and the team hopes to pinpoint precisely where in Zambia the elephants were poached.

The African elephant population was more than halved by poachers between 1979 and 1987, from 1.3 million to 600,000 animals. The Convention on International Trade in Endangered Species, or CITES, banned the ivory trade in 1989.

-- From News Services