Posted on 07/05/2006 5:35:59 PM PDT by blam
Starshade brings fresh hope in search for alien life
By Roger Highfield, Science Editor
(Filed: 06/07/2006)
The quest to find Earth-like planets where alien life may thrive is boosted today by a professor who has unveiled plans for a gigantic, daisy-shaped space shield.
Although large planets, similar to Jupiter, have already been spotted outside our solar system, the orbiting shield should allow astronomers to make out much smaller and more habitable planets.
Such so-called "Goldilocks planets" would be close enough to their neighbouring star so as to be not too hot and not too cold to support life.
The daisy shield - a thin, plastic starshade technically known as an "occulter" - effectively blocks out starlight, enabling astronomers to see further into space.
The structure is unveiled today in the journal Nature by Prof Webster Cash, of the University of Colorado at Boulder, and, most significantly, is being backed by the American space agency, Nasa.
A telescope trailing thousands of miles behind the cosmic daisy would be able to image light from distant planets, skimming by the giant petals without being swamped by light from the parent stars, said Prof Cash.
Researchers could then identify planetary features like oceans, continents, polar caps and cloud banks, and even detect biomarkers - signs of life - like methane, oxygen and water, if they exist.
"We think this is a compelling concept, particularly because it can be built today with existing technology," said Prof Cash. "We will be able to study Earth-like planets tens of trillions of miles away and chemically analyse their atmospheres for signs of life."
The study provides mathematical solutions to optical challenges, like the bending and scattering of light between the pliable, 50 metre-diameter starshade and the space telescope, which would orbit in tandem roughly 15,000 miles apart. The secret to this lies in the petal shapes on the shield.
Scientists would launch the telescope and starshade into an orbit roughly one million miles away, then remotely unfurl the starshade and use small thrusters to move it into lines of sight of nearby stars.
Prof Cash likened the effect of the starshade to a cricket player using his hand to block the sunlight as he tracked a ball. "We would use the starshade as a giant hand to suppress the light emanating from a central star by a factor of about 10 billion," he said.
"For over a century, science fiction writers have speculated on the existence of Earth-like planets around nearby stars. If they actually exist, use of an occulter could find them within the next decade."
In recent years, more than 175 planets have been discovered orbiting other stars.
How many of the aliens will apply for green cards?
I think they can find lots of alien life in Hollywood California.
Doesn't sound too workable to me.
15,000 miles apart?
On a more serious note, this is, in a word, cool. An artifical eclipse is a unique method of observing planets orbit a distant star.
No such thing as "aliens". Sorry. We are the ONLY sentient life in the universe. Even our lower animals, like Democrats, are smarter than any other life in the universe.
Make that "life as we know it".
They don't need no stinkin' green cards!
ALL THESE WORLDS ARE YOURS EXCEPT EUROPA. ATTEMPT NO LANDINGS THERE.
I really do believe our imaging technology will allow us to see and image extrasolar planets as well as we see those in our own solar system within the next couple of decades.
use the starshade here to block the sun... global warming, ha... just send the "blue blocker 3000" up into orbit!
Ping
Space alien ping...er...undocumented pan-galactic immigrant ping.
I wonder if Elaine (from Seinfeld) has heard about this daisy ... she wanted to corner the market don'tchaknow.
By that time, we are likely to see small objects on Mars with the clarity that our spysats can read license plates.
Thanks WCF!
Dave, Hope you and yours are . . . experiencing more and more of what you most want and need.
I haven't checked this post out. Perhaps it's worth a ping to the list.
LUB,
X-Planets ( extrasolar planets, and the various planets X )
Our Tiny Little Minds | various | self et al
Posted on 06/09/2006 1:50:42 PM EDT by SunkenCiv
http://www.freerepublic.com/focus/f-bloggers/1646385/posts
55 posted on 07/07/2006 11:18:47 AM EDT by SunkenCiv
http://www.freerepublic.com/focus/f-bloggers/1646385/posts?page=55#55
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