history of robotics

~ 350 B.C
The brilliant Greek mathematician, Archytas ('ahr 'ky tuhs') of Tarentum builds a mechanical bird dubbed "the Pigeon" that is propelled by steam. It serves as one of histories earliest studies of flight, not to mention probably the first model airplane.

~ 322 B.C.
The Greek philosopher Aristotle writes...

“If every tool, when ordered, or even of its own accord, could do the work that befits it... then there would be no need either of apprentices for the master workers or of slaves for the lords.”

...hinting how nice it would be to have a few robots around.

~ 200 B.C.
The Greek inventor and physicist Ctesibus ('ti sib ee uhs') of Alexandria designs water clocks that have movable figures on them. Water clocks are a big breakthrough for timepieces. Up until then the Greeks used hour glasses that had to be turned over after all the sand ran through. Ctesibus' invention changed this because it measured time as a result of the force of water falling through it at a constant rate. In general, the Greeks were fascinated with automata of all kinds often using them in theater productions and religious ceremonies.

1495
Leonardo DaVinci designs a mechanical device that looks like an armored knight. The mechanisms inside "Leonardo's robot" are designed to make the knight move as if there was a real person inside. Inventors in medieval times often built machines like "Leonardo's robot" to amuse royalty.

1738
Jacques de Vaucanson begins building automata in Grenoble, France. He builds three in all. His first was the flute player that could play twelve songs. This was closely followed by his second automaton that played a flute and a drum or tambourine, but by far his third was the most famous of them all. The duck was an example of Vaucanson's attempt at what he called "moving anatomy", or modeling human or animal anatomy with mechanics." The duck moved, quacked, flapped it's wings and even ate and digested food.

1770
Swiss clock makers and inventors of the modern wristwatch Pierre Jaquet-Droz and later joined by his son Henri-Louis Jaquet-Droz start making automata for European royalty. They create three dolls, each with a unique function. One can write, another plays music, and the third draws pictures.

1801
Joseph Jacquard builds an automated loom that is controlled with punched cards. Punch cards are later used as an input method for some of the 20th centuries earliest computers.

1822
Charles Babbage demonstrates a prototype of his "Difference Engine" to the Royal Astronomical Society. He continues his work by designing an even more ambitious project "the Analytical Engine" that reportedly was to use punch cards inspired by Joseph Jacquard's invention. During his lifetime he never produces a functional version of either machine. Despite this shortcoming he is often heralded as the "Father of the Computer" and his work lives on as the foundation for the binary numbering system that is the basis of modern computers.

1847
George Boole represents logic in mathematical form with his Boolean Algebra.

1898
Nikola Tesla builds and demonstrates a remote controlled robot boat at Madison Square Garden.

1921
Czech writer Karel Capek introduced the word "Robot" in his play "R.U.R" (Rossuum's Universal Robots). "Robot" in Czech comes from the word "robota", meaning "compulsory labor"

1926
Fritz Lang's movie "Metropolis" is released. "Maria" the female robot in the film is the first robot to be projected on the silver screen.

1936
Alan Turing introduces the concept of a theoretical computer called the Turing Machine. Despite being a fundamental advance in computer logic it also spawns new schools in Mathematics.

1940
Issac Asimov produces a series of short stories about robots starting with "A Strange Playfellow" (later renamed "Robbie") for Super Science Stories magazine. The story is about a robot and its affection for a child that it is bound to protect. Over the next 10 years he produces more stories about robots that are eventually recompiled into the volume "I, Robot" in 1950.

Asimov is generally credited with the popularization of the term "Robotics" which was first mentioned in his story "Runaround" in 1942. But probably Issac Asimov's most important contribution to the history of the robot is the creation of his Three Laws of Robotics:

1. A robot may not injure a human being, or, through inaction, allow a human being to come to harm.

2. A robot must obey the orders given it by human beings except where such orders would conflict with the First Law.

3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.

Asimov later adds a "zeroth law" to the list:

Zeroth law: A robot may not injure humanity, or, through inaction, allow humanity to come to harm.

1946
George Devol patents a playback device for controlling machines.

1950
Alan Turing publishes Computing Machinery and Intelligence in which he proposes a test to determine whether or not a machine has gained the power to think for itself. It becomes known as the "Turing Test".

1951
The Day the Earth Stood Still premieres in theaters. The movie features an alien named Klaatu and his robot Gort.

1956
Alan Newell and Herbert Simon create the Logic Theorist, the first "expert system". It is used to help solve difficult math problems.

1956
Aided by a grant from the Rockefeller Foundation John McCarthy, Marvin Minsky, Nat Rochester and Claude Shannon organize The Dartmouth Summer Research Project on Artificial Intelligence at Dartmouth College. The term "artificial intelligence" is coined as a result of this conference.

1959
John McCarthy and Marvin Minsky start the Artificial Intelligence Laboratory at the Massachusetts Institute of Technology (MIT).

1961
Heinrich Ernst develops the MH-1, a computer operated mechanical hand at MIT.

1962
The first industrial arm robot - the Unimate - is introduced. It is designed to complete repetitive or dangerous tasks on a General Motors assembly line.

1963
John McCarthy leaves MIT to start the Artificial Intelligence Laboratory at Stanford University.

1966
The Stanford Research Institute (later to be known as SRI Technology) creates Shakey the first mobile robot to know and react to its own actions. Amongst other achievements SRI was also the research institute that helped bring us modern day laundry detergent in the development of Tide.

1966
An artificial intelligence program named ELIZA is created at MIT by Joseph Weizenbaum. ELIZA functions as a computer psychologist that manipulates its users statements to form questions. Weizenbaum is disturbed at how quickly people put faith in his little program.

1967
Richard Greenblatt writes, MacHack, a program that plays chess, in response to a recent article written by Hurbert Dreyfus where he suggests, as a critique to efforts in artificial intelligence, that a computer program could never beat him in a game of chess. When the program is finished and Dreyfus is invited to play the computer he leads for most of the game but ultimately loses in the end in a close match. Greenblatt's program would be the foundation for many future chess programs, ultimately culminating in Big Blue the chess program that beats chess Grand Master Gary Kasparov.

1968
Stanley Kubrick makes Arthur C. Clark's, 2001: A Space Odyssey into a movie. It features HAL, an onboard computer that decides it doesn't need its human counterparts any longer. Hear HAL by clicking here.

1969
Victor Scheinman, a Mechanical Engineering student working in the Stanford Artificial Intelligence Lab (SAIL) creates the Stanford Arm. The arm's design becomes a standard and is still influencing the design of robot arms today.

1970
Stanford University produces the Stanford Cart. It is designed to be a line follower but can also be controlled from a computer via radio link.

1971
The film Silent Running is released starring Bruce Dern. Bruce's co-stars are three robot drones Huey, Dewey and Louie.

1974
Victor Scheinman forms his own company and starts marketing the Silver Arm. It is capable of assembling small parts together using touch sensors.

1976
Shigeo Hirose designs the Soft Gripper at the Tokyo Institute of Technology. It is designed to wrap around an object in snake like fashion.

1977
Star Wars is released. George Lucas' movie about a universe governed by the force introduces watchers to R2-D2 and C-3PO. The movie creates the strongest image of a human future with robots since the 1960's and inspires a generation of researchers.

1977
Deep space explorers Voyagers 1 and 2 launch from the Kennedy Space Flight Center.

1979
The Robotics Institute at Carnegie Mellon University is established.

1979
The Stanford Cart is rebuilt by Hans Moravec. He adds a more robust vision system allowing greater autonomy. These are some of the first experiments with 3D environment mapping.

1980
Seymour Papert publishes Mindstorms: Children, Computers, and Powerful Ideas where he advocates constructionism, or learning through doing.

1981
Takeo Kanade builds the direct drive arm. It is the first to have motors installed directly into the joints of the arm. This change makes it faster and much more accurate than previous robotic arms.

1982
"A new life awaits you on the Off-World colonies." Blade Runner is released. This Ridley Scott film is based on the Philip K. Dick story "Do Androids Dream of Electric Sheep?" and starred Harrison Ford as Rick Deckard a retired Blade Runner that hunted Replicants (or illegal mutinous androids).

1986
LEGO and the MIT Media Lab colaborate to bring the first LEGO based educational products to market. LEGO tc Logo is used by in the classrooms of thousands of elementary school teachers.

1986
Honda begins a robot research program thats starts with the premise that the robot "should coexist and cooperate with human beings, by doing what a person cannot do and by cultivating a new dimension in mobility to ultimately benefit society."

1989
A walking robot named Genghis is unveiled by the Mobile Robots Group at MIT. It becomes known for the way it walks, popularly referred to as the "Genghis gait".

1989
At MIT Rodney Brooks and A. M. Flynn publish the paper "Fast, Cheap and Out of Control: A Robot Invasion of the Solar System" in the Journal of the British Interplanetary Society. The paper changes rover research from building the one, big, expensive robot to building lots of little cheap ones. The paper also makes the idea of building a robot somewhat more accessible to the average person.

1989
Dr. Seymour Papert becomes the LEGO Professor of Learning Research.

1992
In an attempt to build a radio controlled vaccuum cleaner Marc Thorpe has the idea to start a robot combat event.

1992
Dr. John Adler came up with the concept of the CyberKnife a robot that images the patient with x-rays to look for a tumor and delivering a pre-planned dose of radiationto the tumor when found.

1993
Dante an 8-legged walking robot developed at Carnegie Mellon University descends into Mt. Erebrus, Antarctica. Its mission is to collect data from a harsh environment similar to what we might find on another planet. The mission fails when, after a short 20 foot decent, Dante's tether snaps dropping it into the crater.

1994
Dante II, a more robust version of its predicessor, descends into the crater of Alaskan volcano Mt. Spurr. The mission is considered a success.

1994
Marc Thorpe starts Robot Wars at Fort Mason center in San Francsico, CA.

1995
The second annual Robot Wars event is held at Fort Mason Center, San Francisco, CA.

1996
A RoboTuna is designed and built by David Barrett for his doctoral thesis at MIT. It is used to study the way fish swim.

1996
Chris Campbell and Stuart Wilkinson turn a brewing accident into inspiration at the University of South Florida. The result is the Gastrobot, a robot that digests organic mass to produce carbon dioxide that is then used for power. They call their creation the "flatulence engine."

1996
Honda debuts the P3, the fruit of its decade long effort to build a humanoid robot.

1996
The third annual Robot Wars event is held at Fort Mason Center, San Francisco, CA.

1997
The first node of the International Space Station is placed in orbit. Over the next several years more components will join it, including a robotic arm designed by Canadian company MD Robotics.

1997
The Pathfinder Mission lands on Mars. Its robotic rover Sojourner, rolls down a ramp and onto Martian soil in early July. It continues to broadcast data from the Martian surface until September.

1998
Tiger Electronics introduces the Furby into the Christmas toy market. It quickly becomes "the toy" to get for the season. Using a variety of sensors this "animatronic pet" can react to its environment and communicate using over 800 phrases in English and their own language "Furbish".

1998
LEGO releases their first Robotics Invention SystemTM 1.0. LEGO names the product line MINDSTORMS after Seymour Papert's seminal work of 1980.

1999
LEGO releases The Robotics Discovery Set, Droid Developer Kit and the Robotics Invention System 1.5.

1999
SONY releases the AIBO robotic pet.

2000
Honda debuts new humanoid robot ASIMO.

2000
The Battlebots event is held in Las Vegas, Nevada.

2000
LEGO releases the MINDSTORMS Robotics Invention SystemTM 2.0

2001
LEGO releases the MINDSTORMS Ultimate Builder's Set

2001
In August, the FDA clears the CyberKnife to treat tumors anywhere in the body.

2002
Honda's ASIMO robot rings the opening bell at the New York Stock Exchange.

2003
June 10th - NASA launches the MER-A "Spirit" rover destined for Mars.
July 7th - NASA launches the MER-B "Opportunity".

2003
SONY releases the AIBO ERS-7 it's 3rd generation robotic pet.

2004
Jan. 4th - After six minutes of holding our breath (during EDL) as it burned and bounced its way to the red planet the robot rover Spirit lands on Mars.

Jan. 23rd - The second Mars Exploration Rover - "Opportunity" safely lands on the Meridium Planum.

NASA's Cassini Spacecraft Continues Making New Discoveri

NASA's Cassini spacecraft continues making new and exciting discoveries. New findings include wandering and rubble-pile moons; new and clumpy Saturn rings; splintering storms and a dynamic magnetosphere.




"For the last seven months it has been a nonstop, science-packed mission. It has been a whirlwind, and already we have many new results," said Dr. Dennis Matson, Cassini project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

Weak, linear density waves caused in Saturn's rings by the small moons Atlas and Pan have yielded more reliable calculations of their masses. The masses imply the moons are very porous, perhaps constructed like rubble piles. They are similar to the moons that shepherd Saturn's F ring, Prometheus and Pandora.

Another discovery was a tiny moon, about 5 kilometers (3 miles) across, recently named Polydeuces. Polydeuces is a companion, or "Trojan" moon of Dione. Trojan moons are found near gravitationally stable points ahead or behind a larger moon. Saturn is the only planet known to have moons with companion Trojan moons.

The new findings, published in this week's edition of the journal Science, include refinements in the orbits of several of Saturn's small satellites. One intriguing result is the eccentric and slightly inclined orbit of Pan in Saturn's A ring. The orbit's shape is significant, as it indicates the type of interaction the moon has with the ring material surrounding it. If Pan's orbit remains eccentric due to this interaction, then planets growing in a disc of material surrounding a star may also have eccentric orbits. This may help explain the eccentric paths of planets orbiting other stars.

Several faint Saturn rings have been discovered in Cassini images. Some lie in various gaps in the rings and may indicate the presence of tiny embedded moons acting as shepherds. Several of the rings are kinked, likely evidence of nearby moons.

Scientists also found Saturn's winds change with altitude, and small storms emerge out of large ones. For the first time, Cassini images captured possible evidence of processes that may maintain the winds on Saturn. The observations offer a glimpse into the process which transfers energy by convection from Saturn's interior to help sustain strong winds.

Other results improve the understanding of Saturn's complex magnetic environment. "Saturn's magnetosphere is truly unique. It's dynamically similar to Jupiter's, but in places it chemically resembles water-based plasmas surrounding comets," said Dr. David Young. Young is Cassini principal investigator for the plasma spectrometer instrument from the Southwest Research Institute, San Antonio.

Another surprising find was made by the ion and neutral mass spectrometer instrument, which measured molecular oxygen ions above Saturn's ring plane. "This is at first surprising since the rings are made of water ice," said Dr. Hunter Waite, principal investigator for the spectrometer from the University of Michigan, Ann Arbor. "This may have important consequences for the identification of spectral features to use in the search for life on extrasolar terrestrial planet systems."

The abundance of molecular oxygen on Earth is uniquely tied to biology. But these new measurements at Saturn suggest there are lifeless processes associated with cold icy surfaces that may produce an independent pathway for the formation of molecular oxygen in atmospheres.

For images and information on the Cassini mission visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL.

NGC 6302: Big, Bright, Bug Nebula

2007 April 29

NGC 6302: Big, Bright, Bug Nebula

Explanation: The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects, and NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the central star of this particular planetary nebula is exceptionally hot though -- shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. Above is a dramatically detailed close-up of the dying star's nebula recorded by the Hubble Space Telescope. Cutting across a bright cavity of ionized gas, the dust torus surrounding the central star is in the upper right corner of this view, nearly edge-on to the line-of-sight. Molecular hydrogen has recently been detected in this hot star's dusty cosmic shroud. NGC 6302 lies about 4,000 light-years away in the arachnologically correct constellation Scorpius.

Tufts researchers find new cost-effective catalyst for hydrogen production for fuel cells

Researchers at Tufts University have discovered that it’s possible to make hydrogen from fossil fuels using far less platinum or gold than current fuel processing technology has required. Their research shows that 90 percent of precious metals used today may be removed from the catalyst without affecting its ability to produce hydrogen.

This finding could have potential cost savings of millions of dollars in the materials required to commercialize the fuel cell technology.

The research will be published in the July 3 edition of "Science Express," the online version of the journal Science that provides rapid electronic publication of timely and important research papers. The article also will be published in Science later this summer.

A fuel cell consists of two electrodes sandwiched around an electrolyte. Hydrogen fed to the one electrode (anode) passes through the electrolyte in the form of protons and combines with oxygen on the other electrode (cathode) making water and producing heat. Electricity is generated in the process. A fuel cell will produce energy in the form of electricity and heat as long as fuel and oxygen are supplied. To produce fuel-cell quality hydrogen, an important step involves the removal of any by-product carbon monoxide, which poisons the fuel cell anode catalyst.

"A lot of people have spent a lot of time studying the properties of gold and platinum nanoparticles that are used to catalyze the reaction of carbon monoxide with water to make hydrogen and carbon dioxide," said Maria Flytzani-Stephanopoulos, professor of chemical and biological engineering at Tufts and the lead researcher of the project. "We find that for this reaction over a cerium oxide catalyst carrying the gold or platinum, metal nanoparticles are not important. Only a tiny amount of the precious metal in non metallic form is needed to create the active catalyst. Our finding will help researchers find a cost-effective way to produce clean energy from fuel cells in the near future"

She and her two colleagues, doctoral student Qi Fu and research professor Howard Saltsburg, were funded by a $300,000 three-year grant from the National Science Foundation, and have filed a provisional patent for their research. Their cutting-edge work in catalytic fuel processing to generate hydrogen for fuel cell applications is one of the major undertakings at Tufts’ Science and Technology Center at the University’s Medford campus.

The Tufts researchers’ article is based on the "water-gas shift" reaction they use to make hydrogen from water and carbon monoxide over cerium oxide loaded with gold or platinum. Typically, a loading of 1-10 weight percent of gold or other precious metals is used to make an effective catalyst. But the Tufts team discovered that, after stripping the gold with a cyanide solution, the catalyst was just as active with a slight amount of the gold remaining – one-tenth the normal amount used.

According to Flytzani-Stephanopoulos, "This finding is significant because it shows that metallic nanoparticles are mere ’spectator species’ for some reactions, such as the water-gas shift. The phenomenon may be more general, since we show that it also holds for platinum and may also hold true for other metals and metal oxide supports, such as titanium and iron oxide."

She adds, "It opens the way for new catalyst designs so more hydrogen can be produced with less precious metal. This can pave the way for cost-effective clean energy production from fuel cells in the near future."

Fuel cells currently are being used on a trial basis in some buses, cars and even hotels, but they’re expensive. It may take up to 10 years until the technology is used in transportation and by the general population. (Since the 1960s, one type of fuel cell has powered NASA’s spacecrafts.)

"We’ve raised the issue of now having to look back and see if less precious metal may be used in other similar applications," said Saltsburg. There’s much more to be done, and that’s what makes the research exciting."

BULK SOURCE OF UNIVERSE'S GAMMA RAYS IDENTIFIED

Scientists at Columbia University and Barnard College have found that the majority of the gamma rays outside of our galaxy are likely emitted by galaxy clusters and other massive structures. This may resolve a 30-year-old mystery as to the origin of the Universe's gamma-ray background.

The finding may also provide new insight about how structure formed in the Universe, as well as the nature of magnetic fields in the intergalactic medium, of which little is currently known.

Caleb Scharf of Columbia University and Reshmi Mukherjee of Barnard College publish this result in an upcoming issue of the Astrophysica Journal. The finding is based on the analysis of a nine-year record of gamma rays arriving at Earth from deep space, collected by NASA's Compton Gamma Ray Observatory throughout the 1990s.

	Animation 2

"This result not only resolves the question of where all these gamma rays are coming from, but provides a new probe of the gravity-driven picture of structure formation in the Universe," said Scharf.

Gamma rays are the highest-energy form of light. In the Milky Way galaxy, gamma rays are largely produced when cosmic rays, atomic particles moving at near light speed, collide with interstellar gas. Black holes and neutron stars are also sources of gamma rays.

Galaxy clusters are the largest gravitationally bound structures in the Universe. The clusters in this analysis contain up to several thousand Milky Way-size galaxies, and they are still accumulating material (gas and whole galaxies) from the surrounding space.

	Image 3

The finding announced today supports a theory of gamma-ray production posed by Prof. Avi Loeb of Harvard University and Prof. Eli Waxman of the Weizmann Institute in Rehovot, Israel. Not unlike a black hole, the sheer mass of a cluster serves as a gravitational drain, drawing in matter at speeds of up to a thousand miles per second. Electrons in this flow are accelerated, with an additional boost from magnetic fields, to near light speed and collide with microwave light, the afterglow from the big bang known as the cosmic microwave background.

These microwave light particles, or photons, are bumped up to the gamma-ray photon energy level. The gamma rays form a halo around the galaxy clusters. Other scientists, however, have suggested that the bulk of the gamma-ray background is produced not by this mechanism but by quasar-type galaxies, called blazars, each powered by a supermassive black hole. This background was discovered by NASA's second Small Astronomy Satellite (SAS-2) in the early 1970s.

	Image 4

Scharf and Mukherjee's new research compared a catalog of 2,469 galaxy clusters with the Compton database. Using sophisticated statistical techniques, they showed that the sky surrounding the most massive clusters was systematically brighter in gamma rays than other regions.

"The more massive the cluster (and greater the gravitational potential), the brighter the gamma-ray halo," said Mukherjee. "The enhancement observed was very similar to that predicted by the Loeb-Waxman theory."

The result announced today also supports the theory of the cosmic web. Scientists say that matter in the Universe forms a cosmic web, in which galaxies are formed along filaments of ordinary matter and dark matter like pearls on a string. Clusters form at the intersection of these filaments. The electrons that fuel the gamma-ray production rush into clusters along these rivers or filaments of matter connecting galaxies and clusters. Thus, gamma rays serve as probes to the early structure-forming epoch of the Universe.

	Image 5

Gamma ray halos around clusters also provides a means to measure intergalactic magnetic fields. Two of the three variables to measure magnetic fields are known: the mass of galaxy clusters and the distribution of the microwave background. The third variable is electron efficiency, which can now be measured by virtue of gamma-ray production.

The Gamma-ray Large Area Space Telescope (GLAST), scheduled for launch in 2006, should resolve gamma-ray haloes around galaxies with unprecedented clarity. GLAST could measure intergalactic magnetic fields and watch the formation of structure in the universe through its gamma-ray eyes, the scientists said.

nasa spitzer first to crack open light of faraday world.

NASA's Spitzer First to Crack Open Light of Faraway Worlds
NASA's Spitzer Space Telescope has captured for the first time enough light from planets outside our solar system, known as exoplanets, to identify molecules in their atmospheres. The landmark achievement is a significant step toward being able to detect possible life on rocky exoplanets and comes years before astronomers had anticipated. "This is an amazing surprise," said Spitzer project scientist Dr. Michael Werner of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We had no idea when we designed Spitzer that it would make such a dramatic step in characterizing exoplanets." Spitzer, a space-based infrared telescope, obtained the detailed data, called spectra, for two different gas exoplanets. Called HD 209458b and HD 189733b, these so-called "hot Jupiters" are, like Jupiter, made of gas, but orbit much closer to their suns. Image right: NASA's Spitzer Space Telescope was recently used to capture spectra, or molecular fingerprints, of two "hot Jupiter" worlds like the one depicted here. This is the first time a spectrum has ever been obtained for an exoplanet, or a planet beyond our solar system. Image credit: NASA/JPL-Caltech + Animation and caption + Related images and briefing materials The data indicate the two planets are drier and cloudier than predicted. Theorists thought hot Jupiters would have lots of water in their atmospheres, but surprisingly none was found around HD 209458b and HD 189733b. According to astronomers, the water might be present but buried under a thick blanket of high, waterless clouds. Those clouds might be filled with dust. One of the planets, HD 209458b, showed hints of tiny sand grains, called silicates, in its atmosphere. This could mean the planet's skies are filled with high, dusty clouds unlike anything seen around planets in our own solar system. "The theorists' heads were spinning when they saw the data," said Dr. Jeremy Richardson of NASA's Goddard Space Flight Center, Greenbelt, Md. "It is virtually impossible for water, in the form of vapor, to be absent from the planet, so it must be hidden, probably by the dusty cloud layer we detected in our spectrum," he said. Richardson is lead author of a Nature paper appearing Feb. 22 that describes a spectrum for HD 209458b. In addition to Richardson's team, two other groups of astronomers used Spitzer to capture spectra of exoplanets. A team led by Dr. Carl Grillmair of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena, Calif., observed HD 189733b, while a team led by Dr. Mark R. Swain of JPL focused on the same planet in the Richardson study, and came up with similar results. Grillmair's results will be published in the Astrophysical Journal Letters. Swain's findings have been submitted to the Astrophysical Journal Letters. A spectrum is created when an instrument called a spectrograph splits light from an object into its different wavelengths, just as a prism turns sunlight into a rainbow. The resulting pattern of light, the spectrum, reveals "fingerprints" of chemicals making up the object. Until now, the only planets for which spectra were available belonged in our own solar system. The planets in the Spitzer studies orbit stars that are so far away, they are too faint to be seen with the naked eye. HD 189733b is 370 trillion miles away in the constellation Vulpecula, and HD 209458b is 904 trillion miles away in the constellation Pegasus. That means both planets are at least about a million times farther away from us than Jupiter. In the future, astronomers hope to have spectra for smaller, rocky planets beyond our solar system. This would allow them to look for the footprints of life -- molecules key to the existence of life, such as oxygen and possibly even chlorophyll. "With these new observations, we are refining the tools that we will one day need to find life elsewhere if it exists," said Swain. "It's sort of like a dress rehearsal." Spitzer was able to tease out spectra from the feeble light of the two planets through what is known as the "secondary eclipse" technique. In this method -- first used by Spitzer in 2005 to directly detect the light from an exoplanet for the first time ( http://www.spitzer.caltech.edu/Media/releases/ssc2005-09/index.shtml ) -- a so-called transiting planet is monitored as it circles behind its star, temporarily disappearing from our Earthly point of view. By measuring the dip in infrared light that occurs when the planet disappears, Spitzer can learn how much light is coming solely from the planet. The technique will work only in infrared wavelengths, where the planet is brighter than in visible wavelengths and stands out better next to the overwhelming glare of its star. In the new studies, Spitzer's spectrograph, which measures infrared light at a range of wavelengths, stared at the two transiting planets as they orbited their stars. This allowed the astronomers to subtract the spectra of the stars from the spectra of the planets plus their stars to obtain spectra of the planets alone. "When we first set out to make these observations, they were considered high risk because not many people thought they would work," said Grillmair. "But Spitzer has turned out to be superbly designed and more than up to the task." Previous observations of HD 209458b by NASA's Hubble Space Telescope revealed individual elements, such as sodium, oxygen, carbon and hydrogen, that bounce around the very top of the planet, a region higher up than that probed in the Spitzer studies and a region where molecules like water would break apart. To do this, Hubble measured changes in the light from the star, not the planet, as the planet passed in front. The observations indicated less sodium than predicted, which again supports the idea that the planet is socked in with high clouds. Astronomers hope to use Spitzer for additional studies of transiting exoplanets, which are those that cross in front of their stars from our point of view. Of the approximately 200 known exoplanets, 14 are transiting. At least three of these in addition to HD 209458b and HD 189733b are candidates for obtaining spectra. Further spectral studies of HD 209458b and HD 189733b will also yield more information about the planets' atmospheres. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA. Spitzer's infrared spectrograph was built by Cornell University, Ithaca, N.Y. Its development was led by Dr. Jim Houck of Cornell.