MUSIC:"Our World" theme
Thisweek on "Our World" ... An update on a Hubble Space Telescope repair... we'll tell you about a computer link that helps a paralyzed primate ... plus how dairy farmers makesure the milk we buy is safe to drink.
SCHUKKEN:"And it really doesn't matter if you milkby hand or you milk with a machine, or you have a thousand cows or you have twocows, there is always a very high risk."
Thosestories, consumer complaints ? and sometimes results ? on our Website of the Week, and more. I'm ArtChimes. Welcome to VOA's science and technology magazine, "OurWorld."
NASAEngineers this week took steps to bring the Hubble Space Telescope back to lifeafter a component on the orbiting observatory failed last month.
Thescience data formatter, as it's called, has a number of housekeeping functions,including preparing data collected by Hubble's instruments for transmissiondown to Earth. It's been working nonstop since Hubble was launched in 1990.
NASAmanager Art Whipple this week said they're not sure why the device failed.
WHIPPLE:"The truthful answer is, we cannot becertain. We can almost never be certain when things are on orbit. And once weget the hardware back here, we'll be able to open up and get a much betteridea. I would remind everyone that this unit operated flawlessly for 18 and ahalf years, which is a pretty good service time on any electronics that areoperating continuously."
Thedevice was built with two sets of circuits, to provide a backup in case offailure. So NASA engineers decided to switch to the backup circuit, which hadnot been used or tested since the telescope went into orbit 18 years ago.
Thefailure of the science data formatter prompted a delay in a space shuttleflight to repair Hubble. That flight has been postponed until February at theearliest. Astronauts will replace the science data formatter with a sparethat's been in storage as well as doing some previously planned upgrades.
Hubblepresumably has many more years of useful astronomy ahead of it, but this mightbe a good time to look back on what the space telescope has accomplished.
LIVIO:"I'm not sure it's evenmeasurable"
MarioLivio is an astrophysicist at the Space Telescope Science Institute, whichoperates the Hubble telescope.
LIVIO:"Hubble contributed to all areas ofastronomy and astrophysics, and in that it is really quite unique. In manycases, Hubble only took hints and suspicions we had about various phenomena andturned them into facts, and in some cases, it of course brought about very bigsurprises."
Liviosays Hubble has given astronomers a window on the universe that they can notget from earth-based telescopes. Of all of the discoveries made by astronomersusing Hubble, he said one is particularly notable? the discovery a decade ago of the force that drives theacceleration of the expanding universe
LIVIO:"There is no question, I think, thatHubble's contribution to the discovery of dark energy has been very unique, andsince the nature of dark energy, you know, is arguably the biggest questionthat physics is facing today, then this contribution stands out."
Althoughground-based telescopes are getting better all the time, Livio says there arestill advantages to putting a telescope in space, out beyond the distorting andfiltering effects of Earth's atmosphere. Certain wavelengths, like ultravioletlight, just don't make it through the atmosphere.
LIVIO:"But more importantly is that invisible light, which is the light we see with our own eyes, the resolution orthe sharpness of vision that Hubble has is really incomparable to anything youcan do from the ground."
Wereached astrophysicist Mario Livio at his office at the Space Telescope ScienceInstitute in Baltimore.
In afirst of its kind study, U.S. researchers have been able to get animals to moveparalyzed muscles using an experimental device stimulated by brain cells.As VOA's Jessica Berman reports,investigators say the research offers hope to people who are paralyzed as aresult of spinal cord injuries.
BERMAN:Using a computer device hooked up to cellsin the brains of monkeys, researchers at the University of Washington found theprimates, whose arms were temporarily paralyzed, were able to move theirimmobilized muscles well enough to play a computer game.
ChetMoritz is lead author of the study appearing this week in the journal .
In ateleconference with reporters describing the work, Moritz says investigatorsfound that neurons that had nothing to do with movement, including thoseresponsible for the senses, worked just as well.