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[One-Minute World News] from [BBC NEWS]

[Science & Environment]
By Jonathan Amos
Science correspondent, BBC News
Page last updated at 11:36 GMT, Friday, 15 January 2010
Herschel space telescope restored to full health
{Hifi experienced a damaging voltage peak in August}
Europe's billion-euro Herschel Space Telescope is fully operational again after engineers brought its damaged instrument back online.

The observatory's HiFi spectrometer was turned off just three months into the mission because of an anomaly that was probably triggered by space radiation.

The Dutch-led consortium that operates HiFi has now switched the instrument across to its reserve electronics.

It says the failure event has been understood and cannot happen again.

"We've had 30 people working on this," said Dr Frank Helmich, the lead scientist on HiFi, from the SRON Netherlands Institute for Space Research.

"I don't watch much television but I know Crime Scene Investigation and this was just such an investigation - but in space! We found out what happened and then we designed all the mitigating measures," he told BBC News.

The HiFi fault has not affected the performance of Herschel's two other instruments - Pacs and Spire.

Strange readings

The European Space Agency (Esa) telescope was launched from Earth last May.

{{THE HERSCHEL SPACE TELESCOPE}
> The observatory is positioned 1.5m km from Earth
> Its instruments sense far-infrared and sub-millimetre radiation
> Its 3.5m diameter mirror is the largest ever flown in space
> Herschel can probe clouds of gas and dust to see stars being born
> It will investigate how galaxies have evolved through time
> The mission will end when its helium refrigerant boils off

Its quest is to study how stars and galaxies form, and how they evolve through cosmic time.

The Heterodyne Instrument for the Far Infrared (HiFi) is is a high-resolution spectrometer.

It is designed to capture and split light into its constituent wavelengths, creating a kind of "fingerprint" that will reveal information on the chemistry of a light source.

HiFi is expected to bring remarkable new insights into the composition and behaviour of the clouds of gas and dust that give rise to stars.

But the instrument was taken offline in August when it started returning anomalous readings.

The detailed inquiry at SRON traced the fault to a failed diode in a Local Oscillator Control Unit (LCU), which is part of the system that helps process the sky signal received by the instrument.

Electronic puzzle

Even though the investigators and their "crime scene" were separated by 1.5 million km, the SRON team was able to establish that the most likely cause was a cosmic ray hitting a microprocessor.

This upset triggered a sequence of hardware and software actions that ultimately resulted in a powerful voltage being sent through the LCU and killing the diode.

HiFi project leader Dr Peter Roelfsema said: "It turned out to be a very complex technological puzzle that we had to solve based on limited information and under a great deal of pressure.

{While Hifi was down, Spire and Pacs took up the observing time}

"But for all researchers involved, quickly finding an answer to this question was a matter of professional pride. We had to - and would - crack the problem with HiFi as soon as humanly possible, but we also had to take the time to be thorough."

Like most space equipment, Hifi has redundant electronics and the instrument is now using its reserve LCU. Measures have also been put in place to ensure another cosmic ray event cannot initiate the same failure sequence.

While Hifi was down, its observing time was used by Pacs and Spire to return stunning new images of the far-infrared and sub-millimetre (radio) Universe.

They will now reciprocate by giving HiFi 50% of the sky time in the next few months. Fortunately, because of the way the telescope is orientated in space, HiFi's most important targets were not due to come into view until early 2010 anyway.

"We will go into a priority science programme," Dr Helmich told BBC News.

"We do not fear that the LCU will misbehave again but we have lost redundancy in our electronics and so we want to do the most important science observations first.

"One of the first targets will be [star forming regions in] Orion. We expect tens of thousands of [spectral] lines to be seen by HiFi that will all need interpretation."

The Herschel mission is expected to last about three years before the superfluid helium that drives its cooling system boils away. At that point, the instruments' detectors will lose their sensitivity.


[UK]
Page last updated at 02:12 GMT, Friday, 15 January 2010
Rival to government drug advisory panel launched
{The government's former chief drugs adviser, David Nutt, on why he set up the panel}
An independent group designed to give "politically neutral" information about the risks of drugs is being launched.

It has been set up by the government's former chief drugs adviser, David Nutt, who was sacked last October for criticising government policy.

The Independent Council on Drug Harms consists of about 20 specialists.

Prof Nutt has said the group will be "very powerful" and its "goal" will be to take over from the official Advisory Council on the Misuse of Drugs.

'Focus on science'

Several former and current ACMD members are among the specialists in drugs, addiction and medicine who have joined the group, which held its first private meeting on Thursday .

{{I think in a way we will take over that particular role of the ACMD}
Professor David Nutt}

BBC home affairs correspondent Danny Shaw said he understood the new organisation had secured funding from a benefactor for three years.

It is also being supported by the Centre for Crime and Justice Studies think tank.

When he announced his plans for the group, Prof Nutt said: "We have a really very, very powerful grouping - more powerful than the ACMD in the past has ever managed to pull together."

He said the new body would provide independent scientific evidence about the effects of drugs.

"I think in a way we will take over that particular role of the ACMD," said Prof Nutt.

"We're going to focus on the science and the ACMD can continue, if it likes, to deal with issues about treatment provision, about social policy etc."

Prof Nutt was sacked by Home Secretary Alan Johnson last October after publicly disagreeing with the government's decision to re-classify cannabis as a Class B drug and not to downgrade ecstasy.

Appointment overshadowed

Five ACMD members then resigned in the row that followed Prof Nutt's departure.

It later emerged that two other ACMD members had also stepped down, though the Home Office said their departures were unrelated to the Nutt affair.

On Wednesday the Home Office named pharmacology specialist Les Iversen as the new chairman of the ACMD, but the appointment was overshadowed by the revelation he had once backed the legalisation of cannabis.

In an article in 2003, Prof Iverson wrote that cannabis had been "incorrectly" classified as a dangerous drug for almost 50 years and said it was one of the "safer" recreational drugs.

However, he told BBC Radio 5 live he had since changed his mind because of new evidence about the dangers of cannabis.

It was the home secretary's prerogative to make decisions about drug classification and accept or reject scientific advice, Prof Iverson added.