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Monday, 27 March, 2000, 11:49 GMT 12:49 UK
Nasa trashes another satellite
A $75m Nasa satellite was badly damaged during a botched pre-flight test last week.

The mission's project manager said an equipment malfunction or software glitch probably caused the mishap that cracked the satellite's solar panels.

The accident occurred at the Jet Propulsion Laboratory in California, already at the centre of criticism over failed missions to Mars.

The 390-kilogram (850-pound) spacecraft was undergoing a vibration test to ensure it could withstand launch when the equipment applied 10 times more force than was intended.

"The building shook, as opposed to something that was just shaking the spacecraft," said Peter Harvey, project manager of the High Energy Solar Spectroscopic Imager (Hessi) mission. "Everybody knew something was wrong."

But he added: "This is not something that was human error - it looks like the machine or software or something. I think JPL is getting hammered here, and it's not fair. They're the best."

The launch of Hessi, originally scheduled for July, has been pushed back to at least January 2001.

Cloned bulls to father calves

Two cloned bulls are set to become fathers, following a successful experiment in which their semen was used to artificially impregnate cows.

The experiment was conducted by Japan's Ministry of Agriculture in conjunction with researchers in Kagoshima Prefecture to determine the ability of cloned animals to reproduce.

Twenty-four cows were artificially inseminated in December using the semen from two bulls cloned by researchers in 1998.

Pregnancy tests now show that 14 of the cows have conceived. Barring complications, the offspring of the cloned bulls will be born in November or December.

The primary purpose of the Japanese cattle-cloning experiments is to produce high-quality beef. Cloned beef is already on sale in Japanese supermarkets.

Heavyweight satellite to deliberately crash

Nasa has confirmed it will deliberately crash an ailing space observatory into a remote area of the Pacific Ocean.

The US space agency said the move would avoid a risk that the 17-tonne spacecraft might smash uncontrolled into a populated area.

The Compton Gamma-Ray Observatory is still in use despite already exceeding its expected lifespan by four years. In nine years of operation, it detected more than 400 gamma ray sources and over 2,500 gamma ray bursts, powerful celestial explosions that still puzzle scientists.

The loss of one of the craft's three gyroscopes prompted Nasa to take the final decision. The gyroscopes help control the craft and if one more were lost assuring a controlled descent would be difficult.

Ed Weiler, Nasa's chief scientist, said: "This was a difficult decision, but the safest option is to bring it down in June. How much science is worth the risk of even one human life?"

A series of rocket firings starting in May will lower the orbit of the $670m Compton Observatory and a final rocket thrust will send the craft into its fiery plunge on 3 June.

The crash is expected to scatter debris along a corridor of ocean 4,000 km (2,500 miles) long and 26 km (16 miles) wide.

Oceans are warming up

The oceans have warmed significantly over the past four decades, according to a study by US government scientists.

The analysis provides new evidence that the Earth may be undergoing long-term climate change.

The broad study of temperature data from the oceans shows that average temperatures have increased by a tenth or a half of a degree, depending on depth, since the 1950s. This increase was described as surprising.

The findings were reported by scientists at the US National Oceanic and Atmospheric Administration. They may also support the findings of computer climate models that suggest more severe temperature increases than are shown by actual historic surface temperature readings.

"We've known the oceans could absorb heat, transport it to subsurface depths and isolate it from the atmosphere. Now we see evidence that this is happening," said Sydney Levitus, chief of NOAA's Ocean Climate Laboratory and principal author of the study.

The report, published in the journal Science, took seven years to compile and examined more than five million temperature readings from the Pacific, Atlantic and Indian oceans, between 1948 and 1996.

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17 Jan 00 | Sci/Tech
Nasa may crash satellite
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