So... the jury on global warming is still out, eh?

The CAUSE is what is at question. Is it natural, manmade or a combinatin of both.

That is the argument

The CAUSE is what is at question. Is it natural, manmade or a combinatin of both.

That is the argument

Remember Global Cooling?
Why scientists find climate change so hard to predict.

WEB EXCLUSIVE
By Jerry Adler
Updated: 4:41 p.m. CT Oct 23, 2006

Oct. 23, 2006 - In April, 1975, in an issue mostly taken up with stories about the collapse of the American-backed government of South Vietnam, NEWSWEEK published a small back-page article about a very different kind of disaster. Citing "ominous signs that the earth's weather patterns have begun to change dramatically," the magazine warned of an impending "drastic decline in food production." Political disruptions stemming from food shortages could affect "just about every nation on earth." Scientists urged governments to consider emergency action to head off the terrible threat of . . . well, if you had been following the climate-change debates at the time, you'd have known that the threat was: global cooling..........

How did NEWSWEEK—or for that matter, Time magazine, which also ran a story on the subject in the mid-1970s—get things so wrong? In fact, the story wasn't "wrong" in the journalistic sense of "inaccurate." Some scientists indeed thought the Earth might be cooling in the 1970s, and some laymen—even one as sophisticated and well-educated as Isaac Asimov—saw potentially dire implications for climate and food production. After all, Ice Ages were common in Earth's history; if anything, the warm "interglacial" period in which human civilization evolved, and still exists, is the exception. The cause of these periodic climatic shifts is still being studied and debated, but many scientists believe they are influenced by small changes in the Earth's orbit around the Sun (including its "eccentricity," or the extent to which it deviates from a perfect circle) and the tilt of its rotation. As calculated by the mathematician Milutin Milankovitch in the 1920s, these factors vary on interlocking cycles of around 20,000, 40,000 and 100,000 years, and if nothing else changed they would be certain to bring on a new Ice Age at some time. In the 1970s, there were scientists who thought this shift might be imminent..........

Well, since many of the planets in our Solar system may be showing signs of warming, the obvious question is :

what do all of these planets have in common , since it ain't people, SUVs or burning of fossil fuels?

real life wrote:

Well, since many of the planets in our Solar system may be showing signs of warming, the obvious question is :

what do all of these planets have in common , since it ain't people, SUVs or burning of fossil fuels?

Real life, I have looked over all the articles you cited as examples. None of these articles support your claim even remotely.

"Jupiter's Spots Disappear Amid Major Climate Change "

This article describes the continually changing and active atmospheric
conditions on Jupiter which have likely been present for billions of years.

"Saturn's Bull's-Eye Marks Its Hot Spot"
Although surprising that a planetary pole can be hot rather than cold, this
is not something that has happened recently.

"Scientists baffled by changes in Saturn's rings"
The information suggests that planetary rings are in a constant state of flux,
and always have been. There is no connection to surface temperature.

"The Worst Weather in the Solar System"
The heat wave they describe on Venus is not a recent change, it happened
billions of years ago. Late breaking news I guess.

"MIT researcher finds evidence of global warming on Neptune's largest moon"
The researchers describe this heating as a seasonal change.

"Global Warming on Pluto Puzzles Scientists"
Once again, the researchers postulate "The change is likely a seasonal event,"

Mars Emerging from Ice Age, Data Suggest
By SPACE.com

posted: 03:00 pm ET
08 December 2003

Scientists have suspected in recent years that Mars might be undergoing some sort of global warming. New data points to the possibility it is emerging from an ice age.

NASA's Mars Odyssey orbiter has been surveying the planet for nearly a full Martian year now, and it has spotted seasonal changes like the advance and retreat of polar ice. It's also gathering data of a possible longer trend.

There appears to be too much frozen water at low-latitude regions -- away from the frigid poles -- given the current climate of Mars. The situation is not in equilibrium, said William Feldman of the Los Alamos National Laboratory.

"One explanation could be that Mars is just coming out of an ice age," Feldman said. "In some low-latitude areas, the ice has already dissipated. In others, that process is slower and hasn't reached an equilibrium yet. Those areas are like the patches of snow you sometimes see persisting in protected spots long after the last snowfall of the winter."

Frozen water makes up as much as 10 percent of the top 3 feet (1 meter) of surface material in some regions close to the equator. Dust deposits may be covering and insulating the lingering ice, Feldman said.

Feldman is the lead scientist for an Odyssey instrument that assesses water content indirectly through measurements of neutron emissions. He and other Odyssey scientists described their recent findings today at the fall meeting of the American Geophysical Union in San Francisco.

"Odyssey is giving us indications of recent global climate change in Mars," said Jeffrey Plaut, project scientist for the mission at NASA's Jet Propulsion Laboratory.

High latitude regions of Mars have layers with differing ice content within the top 20 inches (half-meter) or so of the surface, researchers conclude from mapping of hydrogen abundance based on gamma-ray emissions.

"A model that fits the data has three layers near the surface," said William Boynton of the University of Arizona, Tucson, team leader for the gamma-ray spectrometer instrument on Odyssey. "The very top layer would be dry, with no ice. The next layer would contain ice in the pore spaces between grains of soil. Beneath that would be a very ice-rich layer, 60 to nearly 100 percent water ice."

Boynton interprets the iciest layer as a deposit of snow or frost, mixed with a little windblown dust, from an era when the climate was colder than nowadays. The middle layer could be the result of changes brought in a warmer era, when ice down to a certain depth dissipated into the atmosphere. The dust left behind collapsed into a soil layer with limited pore space for returning ice.

More study is needed to determine for sure what's going on.

Other Odyssey instruments are providing other pieces of the puzzle. Images from the orbiter's camera system have been combined into the highest resolution complete map ever made of Mars' south polar region.

"We can now accurately count craters in the layered materials of the polar regions to get an idea how old they are," said Phil Christensen of Arizona State University, Tempe, principal investigator for the camera system.

Temperature information from the camera system's infrared imaging has produced a surprise about dark patches that dot bright expanses of seasonal carbon-dioxide ice.

"Those dark features look like places where the ice has gone away, but thermal infrared maps show that even the dark areas have temperatures so low they must be carbon-dioxide ice." Christensen said. "One possibility is that the ice is clear in these areas and we're seeing down through the ice to features underneath."

Global Warming on Mars?

A study of the ice caps on Mars may show that the red planet is experiencing a warming trend.

After decades of thinking that the ice caps on Mars were mostly carbon dioxide (dry ice), planetary geologists are starting to think that those caps may be mostly fresh water ice instead.

Caltech planetary scientists have been keeping a close eye on the dozens of deep, wide pits in the southern martian ice caps. These pits have been growing larger every year, but they never get any deeper.

The scientists believe this means that there is a layer of dry ice that is evaporating off of a thicker layer of water ice. The yearly increases in evaporation may be caused by a global warming trend happening on Mars.

If both Mars and Earth are experiencing global warming, then perhaps there is a larger phenomenon going on in the Solar System that is causing their global climates to change.

New Storm on Jupiter Hints at Climate Change
By Sara Goudarzi
Staff Writer
posted: 04 May 2006
01:00 pm ET

A storm is brewing half a billion miles away and in a rare event, astronomers get to watch it closely.

Jupiter is growing a new red spot and the Hubble Space Telescope is photographing the scene. Backyard astronomers have been following the action, too.

"Red Spot Jr." as it is being called, formed after three white oval-shaped storms—two of which were at least 90 years old—merged between 1998 and 2000.

A similar merger took place centuries ago and formed the bigger and legendary Great Red Spot, a storm twice as big as Earth and almost 300 years old.

Close look

Close inspections of Red Spot Jr., in Hubble images released today, reveal that similar to the Great Red Spot, the more recently developed storm rises above the top of the main cloud deck on Jupiter.

Little is known about how storms form on the giant planet. They are often described as behaving similar to hurricanes on Earth. Some astronomers believe that the spots dredge up material deep below Jupiter's clouds and lift it to where the Sun's ultraviolet light chemically alters it to give it a red hue.

The latest images could provide evidence that Jupiter is in the midst of a global change that can modify temperatures by as much as 10 degrees Fahrenheit on different parts of the globe.

The study was led jointly by Imke de Pater and Philip Marcus of University of California, Berkeley.

"The storm is growing in altitude," de Pater said. "Before when they were just ovals they didn't stick out above the clouds. Now they are rising."

This growth signals a temperature increase in that region, she said.

Marking change

The global change cycle began when the last of the white oval-shaped storms formed south of the Great Red Spot in 1939. As the storms started to merge between 1998 and 2000, the mixing of heat began to slow down at that latitude and has continued slowing ever since.

The movement of heat from the equator to Jupiter's south pole is expected to stop at 34 degrees southern latitude, where Red Spot Jr. is forming.

This will create a big wall and stop the mixing of heat and airflow, the thinking goes. As a result, areas around the equator become warmer, while the poles can start to cool down.

Researcher predicts global climate change on Jupiter as giant planet's spots disappear

By Sarah Yang, Media Relations | 21 April 2004

BERKELEY - If a University of California, Berkeley, physicist's vision of Jupiter is correct, the giant planet will be in for a major global temperature shift over the next decade as most of its large vortices disappear.

But fans of the Great Red Spot can rest easy. The most famous of Jupiter's vortices - which are often compared to Earth's hurricanes - will stay put, largely because of its location near the planet's equator, says Philip Marcus, a professor at UC Berkeley's Department of Mechanical Engineering.

Using whirlpools and eddies for comparison, Marcus bases his forecast on principles learned in junior-level fluid dynamics and on the observation that many of Jupiter's vortices are literally vanishing into thin air.

"I predict that due to the loss of these atmospheric whirlpools, the average temperature on Jupiter will change by as much as 10 degrees Celsius, getting warmer near the equator and cooler at the poles," says Marcus. "This global shift in temperature will cause the jet streams to become unstable and thereby spawn new vortices. It's an event that even backyard astronomers will be able to witness."

According to Marcus, the imminent changes signal the end of Jupiter's current 70-year climate cycle. His surprising predictions are published in the April 22 issue of the journal Nature.

Jupiter's stormy atmosphere has a dozen or so jet streams that travel in alternating directions of east and west, and that can clock speeds greater than 330 miles per hour. As on Earth, vortices on Jupiter that rotate clockwise in the northern hemisphere are considered anticyclones, while those that spin counterclockwise are cyclones. The opposite is true in the southern hemisphere, where clockwise vortices are cyclones and counterclockwise spinners are anticyclones.

The Great Red Spot, located in the southern hemisphere, holds title as Jupiter's largest anticyclone; spanning 12,500 miles wide, it is large enough to swallow Earth two to three times over.

Unlike the cyclonic storms on Jupiter, Earth's hurricanes and storms are associated with low-pressure systems and dissipate after days or weeks. The Great Red Spot, in comparison, is a high-pressure system that has been stable for more than 300 years, and shows no signs of slowing down.

About 20 years ago, Marcus developed a computer model showing how the Great Red Spot emerged out of and endured in the chaotic turbulence of Jupiter's atmosphere. His efforts to explain the dynamics governing it and other vortices on Jupiter led to his current projection of the planet's impending climate change.

He says the current 70-year cycle began with the formation of three distinct anticyclones - the White Ovals - that developed south of the Great Red Spot in 1939. "The birth of the White Ovals was seen through telescopes on Earth," he says. "I believe we're in for a similar treat within the next 10 years."

Marcus says the first stage of the climate cycle involves the formation of vortex streets which straddle the westward jet streams. Anticyclones form on one side of the street, while cyclones form on the other side, with no two vortices rotating in the same direction directly adjacent to each other.

Most of the vortices slowly decay with turbulence. By stage two of the cycle, some vortices become weak enough to get trapped in the occasional troughs, or Rossby waves, that form in the jet stream. Multiple vortices can get caught in the same trough. When they do, they travel bunched together, and turbulence can easily make them merge. When the vortices are weak, trapping and merging continues until only one pair is left on each vortex street.

The noted disappearance of two White Ovals, one in 1997 or 1998 and a second in 2000, exemplified the merging of the vortices in stage two, and as such, signaled the "beginning of the end" of Jupiter's current climate cycle, says Marcus.

Why would the merger of vortices affect global temperature? Marcus says the relatively uniform temperature of Jupiter - where the temperatures at the poles are nearly the same as they are at the equator - is due to the chaotic mixing of heat and airflow from the vortices.

"If you knock out a whole row of vortices, you stop all the mixing of heat at that latitude," says Marcus. "This creates a big wall and prevents the transport of heat from the equator to the poles."

Once enough vortices are gone, the planet's atmosphere will warm at the equator and cool at the poles by as much as 10 degrees Celsius in each region, which is stage three of the climate cycle.

This temperature change destabilizes the jet streams, which will react by becoming wavy. The waves steepen and break up, like they do at the beach, but they then roll up into new large vortices in the cycle's fourth stage. In the fifth and final stage of the climate cycle, the new vortices decrease in size, and they settle into the vortex streets to begin a new cycle.

The weakening of the vortices is due to turbulence and happens gradually over time. It takes about half a century for newly formed vortices to gradually shrink down enough to be caught up in a jet stream trough, says Marcus.

Fortunately, the Great Red Spot's proximity to the equator saves it from destruction. Unlike Jupiter's other vortices, the Great Red Spot survives by "eating" its neighboring anticyclones, says Marcus.

Marcus notes that his theory of Jupiter's climate cycle relies on the existence of a roughly equal number of cyclones and anticyclones on the planet.

Since the telltale signs of vortices are the clouds they create, it was easy to miss the presence of long-lived cyclones, says Marcus. He explains that unlike an anticyclone's distinct spot, cyclones create patterns of filamentary clouds that are less clearly defined.

"On the face of it, it is easy to think that Jupiter is dominated by anticyclones because their spinning clouds show up clearly as bull's-eyes," says Marcus.

In the paper in Nature, Marcus presents a computer simulation showing that the warm center and cooler perimeter of a cyclone creates the appearance of the filamentary clouds. In contrast, anticyclones have cold centers and warmer perimeters. Ice crystals that form in the anticyclone's center swell up and move to the sides where they melt, creating a darker swirl surrounding a lighter colored center.

Marcus approaches the study of planetary atmospheres from the untraditional viewpoint of a fluid dynamicist. "I'm basing my predictions on the relatively simple laws of vortex dynamics instead of using voluminous amounts of data or complex atmospheric models," says Marcus.

Marcus says the lesson of Jupiter's climate could be that small disturbances can cause global changes. However, he cautions against applying the same model to Earth's climate, which is influenced by many different factors, both natural and manmade.

"Still, it's important to have different 'labs' for climate," says Marcus. "Studying other worlds helps us better understand our own, even if they are not directly analogous."

Marcus's research is supported by grants from the NASA Origins Program, the National Science Foundation Astronomy and Plasma Physics Programs and the Los Alamos National Laboratory.

Global Warming on Pluto Puzzles Scientists
By Robert Roy Britt
Senior Science Writer
posted: 01:25 pm ET
09 October 2002

In what is largely a reversal of an August announcement, astronomers today said Pluto is undergoing global warming in its thin atmosphere even as it moves farther from the Sun on its long, odd-shaped orbit.

Pluto's atmospheric pressure has tripled over the past 14 years, indicating a stark temperature rise, the researchers said. The change is likely a seasonal event, much as seasons on Earth change as the hemispheres alter their inclination to the Sun during the planet's annual orbit.

They suspect the average surface temperature increased about 3.5 degrees Fahrenheit, or slightly less than 2 degrees Celsius.

Pluto remains a mysterious world whose secrets are no so easily explained, however. The warming could be fueled by some sort of eruptive activity on the small planet, one astronomer speculated.

The increasing temperatures are more likely explained by two simple facts: Pluto's highly elliptical orbit significantly changes the planet's distance from the Sun during its long "year," which lasts 248 Earth years; and unlike most of the planets, Pluto's axis is nearly in line with the orbital plane, tipped 122 degrees. Earth's axis is tilted 23.5 degrees.

Though Pluto was closest to the Sun in 1989, a warming trend 13 years later does not surprise David Tholen, a University of Hawaii astronomer involved in the discovery.

"It takes time for materials to warm up and cool off, which is why the hottest part of the day on Earth is usually around 2 or 3 p.m. rather than local noon," Tholen said. "This warming trend on Pluto could easily last for another 13 years."

Stellar observations

The conclusion is based on data gathered during a chance passage of Pluto in front of a distant star as seen from Earth. Such events, called occultations, are rare, but two of them occurred this summer.

In the occultations, which are like eclipses, astronomers examined starlight as it passed through Pluto's tenuous atmosphere just before the planet blotted out the light.

The first occultation, in July, yielded limited data because of terrestrial cloud cover above key telescopes. Marc Buie, an astronomer at Lowell Observatory, scrambled to observe the event from northern Chile using portable 14-inch (0.35-meter) telescope. Afterward, Buie said he was baffled by what seemed to be global cooling of Pluto's atmosphere punctuated by some surface warming.

Then on Aug. 20, Pluto passed in front of a different star. The latter event provided much better data captured by eight large telescopes and seems to clarify and mostly reverse the earlier findings.

The results were compared to studies from 1988, the last time Pluto was observed eclipsing a star.

James Elliot of MIT led a team of astronomers who coordinated their observations and presented the findings today at the annual meeting of the American Astronomical Society's (AAS) Division for Planetary Sciences in Birmingham, Ala.

Elliot said the Aug. 20 occultation was the first that allowed such a deep probing of the composition, pressure and the always-frigid temperature of Pluto's atmosphere, which ranges from -391 to -274 degrees Fahrenheit (-235 to -170 degrees Celsius).

Volcanoes on Pluto?

Elliot hinted at the possibility of another factor fueling Pluto's warming trend.

He compared Pluto to Triton, a moon of Neptune. Both have atmospheres made mostly of nitrogen. In 1997, Triton occulted a star and astronomers found that its atmosphere had warmed since the last observations were made in 1989 during the Voyager mission. Back then, Voyager found dark material rising above Triton, indicating possible eruptive activity.

"There could be more massive activity on Pluto, since the changes observed in Pluto's atmosphere are much more severe," Elliot said. "The change observed on Triton was subtle. Pluto's changes are not subtle."

There is no firm evidence that Pluto is volcanically active, but neither is there evidence to rule out that possibility. Even the Hubble Space Telescope can barely make out Pluto's surface.

Elliot added that the process affecting Pluto's temperature is complex. "We just don't know what is causing these effects," he said.

Let's go there

Elliot and others believe this poor understanding of our solar system's tiniest planet is grounds for sending a robot to investigate. Pluto is the only planet not visited by a spacecraft.

NASA has shelved a mission that would explore Pluto and the Kuiper Belt of frozen objects in which it resides.

Congress, however, appears to view the mission as worthy of some funds. A House budget panel this week followed the lead of the Senate in approving $105 million for the mission. If final approval comes, NASA would be compelled to undertake the project.

Interestingly, while Pluto's atmosphere has been growing warmer in recent years, astronomers have argued that a Pluto mission must launch by 2006, lest it miss the opportunity to study Pluto's atmosphere before it completely freezes out for the winter.

Tentative mission plans call for a robotic probe that would not reach Pluto for several years, making a flyby sometime prior to 2020 prior to investigating other objects deeper in the solar system.

Meanwhile, astronomers are looking forward to a space telescope called SOFIA, slated to begin operations in 2004. SOFIA will carry an instrument designed specifically to observe occultations and is expected to be employed when Pluto passes in front of other stars in coming years.

The Pluto observations this summer were funded by NASA, the Research Corporation and the National Science Foundation. Observations were made using the telescopes at the Mauna Kea Observatory, Haleakala, Lick Observatory, Lowell Observatory and the Palomar Observatory.

Pluto is undergoing global warming, researchers find

October 9, 2002

BIRMINGHAM, Ala.--Pluto is undergoing global warming, as evidenced by a three-fold increase in the planet's atmospheric pressure during the past 14 years, a team of astronomers from Massachusetts Institute of Technology (MIT), Williams College, the University of Hawaii, Lowell Observatory and Cornell University announced in a press conference today at the annual meeting of the American Astronomical Society's (AAS) Division for Planetary Sciences in Birmingham, AL.

The team, led by James Elliot, professor of planetary astronomy at MIT and director of MIT's Wallace Observatory, made this finding by watching the dimming of a star when Pluto passed in front of it Aug. 20. The team carried out observations using eight telescopes at Mauna Kea Observatory, Haleakala, Lick Observatory, Lowell Observatory and Palomar Observatory. Data were successfully recorded at all sites.

An earlier attempt to observe an occultation of Pluto on July 19 in Chile was not highly successful. Observations were made from only two sites with small telescopes because the giant telescopes and other small telescopes involved lost out to bad weather or from being in the wrong location that day. These two occultations were the first to be successfully observed for Pluto since 1988.

Elliot said the new results have surprised the observers, who as recently as July thought that Pluto's atmosphere may be cooling. "From the July data, we knew that Pluto's atmosphere had changed since 1988, but the August data allowed us to probe much more deeply into Pluto's atmosphere and have given us a more accurate picture of the changes that have occurred," he said.

Jay Pasachoff, an astronomy professor at Williams College, said that Pluto's global warming was "likely not connected with that of the Earth. The major way they could be connected is if the warming was caused by a large increase in sunlight. But the solar constant--the amount of sunlight received each second--is carefully monitored by spacecraft, and we know the sun's output is much too steady to be changing the temperature of Pluto."

Pluto's orbit is much more elliptical than that of the other planets, and its rotational axis is tipped by a large angle relative to its orbit. Both factors could contribute to drastic seasonal changes.

Since 1989, for example, the sun's position in Pluto's sky has changed by more than the corresponding change on the Earth that causes the difference between winter and spring. Pluto's atmospheric temperature varies between around minus 235 and minus 170 degrees Celsius, depending on the altitude above the surface. The main gas in Pluto's atmosphere is nitrogen, and Pluto has nitrogen ice on its surface that can evaporate into the atmosphere when it gets warmer, causing an increase in surface pressure. If the observed increase in the atmosphere also applies to the surface pressure--which is likely the case--this means that the average surface temperature of the nitrogen ice on Pluto has increased slightly less than 2 degrees Celsius over the past 14 years.

Marc Buie, an astronomer at Lowell Observatory, has been measuring the amount of sunlight reflected by Pluto. "The pressure increase can be explained if the average amount of sunlight reflected by the surface has decreased, which means that more heat is absorbed from the sun," he said. "This could be the reason that the pressure has been pumped up."

David Tholen, an astronomer at the University of Hawaii who measured the size of Pluto in the late 1980s using a series of occultations and eclipses involving Pluto's satellite, noted that even though Pluto was closest to the sun in 1989, a warming trend 13 years later shouldn't be unexpected. "It takes time for materials to warm up and cool off, which is why the hottest part of the day on Earth is usually around 2 or 3 p.m. rather than local noon, when sunlight is the most intense," Tholen said. Because Pluto's year is equal to about 250 Earth years, 13 years after Pluto's closest approach to the Sun is like 1:15 p.m. on Earth. "This warming trend on Pluto could easily last for another 13 years," Tholen estimated.

Pluto and Neptune's largest moon, Triton, are presently about the same distance from the sun, and each has a predominantly nitrogen atmosphere (with a surface pressure 100,000 times less than that on Earth), so one might expect similar processes to be occurring on these two bodies.

A 1997 occultation of a star by Triton revealed that its surface had warmed since the Voyager spacecraft first explored it in 1989. On Triton, "Voyager saw dark material rising up as much as 12 km above the surface, indicating some kind of eruptive activity," Elliot said. "There could be more massive activity on Pluto, since the changes observed in Pluto's atmosphere are much more severe. The change observed on Triton was subtle. Pluto's changes are not subtle."

Researchers study faraway objects through occultations--eclipse-like events in which a body (Pluto in this case) passes in front of a star, blocking the star's light from view. By recording the dimming of the starlight over time, astronomers can calculate the density, pressure and temperature of Pluto's atmosphere. Observing two or more occultations at different times provides researchers with information about changes in the planet's atmosphere. The structure and temperature of Pluto's atmosphere was first determined during an occultation in 1988. Pluto's brief pass in front of a different star on July 19 led researchers to believe that a drastic atmospheric change was under way, but it was unclear whether the atmosphere was warming up or cooling down.

The data resulting from this occultation, when Pluto passed in front of a star known as P131.1, led to the current results. "This is the first time that an occultation has allowed us to probe so deeply into Pluto's atmosphere with a large telescope, which gives a high spatial resolution of a few kilometers," Elliot said.

From MIT, in addition to Elliot, researchers involved were physics seniors Katie Carbonari, Erica McEvoy and Alison Klesman; Kelly Clancy, technical assistant in earth, atmospheric and planetary sciences (EAPS); EAPS graduate student Susan Kern, MIT graduate Joyance Meechai (S.B. 2000); David Osip, EAPS research scientist; Michael Person, EAPS graduate student; and aeronatucs and astronautics junior Shen Qu.

NASA is still deciding whether to send a spacecraft to Pluto, the only planet not yet observed at close range. The Pluto-Kuiper Belt mission in the New Horizons Program, if approved, would be launched in 2006 and would reach Pluto 10 years later. This mission will seek to answer questions about the surfaces, atmospheres, interiors and space environments of the solar system's outermost objects, including Pluto and its moon, Charon.

Researchers are looking forward to observing additional Pluto occultations in the years before the Pluto-Kuiper mission flies by Pluto. Of particular interest is the prospect of using SOFIA, a 2.5-meter airborne telescope being built by NASA in collaboration with the German space agency, for Pluto-occultation events when it begins operating in 2004. Edward Dunham, who leads the occultation effort at Lowell Observatory, also is leading a team that is building HIPO, a SOFIA instrument designed specifically to observe occultations. The combination of HIPO and SOFIA will provide very high-quality data on a much more frequent basis than is possible using ground-based telescopes alone.

"This is a very complex process, and we just don't know what is causing these effects" on Pluto's surface, Elliot said. "That's why you need to send a mission."

This work is funded by Research Corporation, the National Science Foundation, and NASA's Planetary Astronomy Program

Of course the changes on other planets (and Earth as well) are cyclical.

That's kinda the whole point of the debate, isn't it?

A picture's worth a thousand words, they say....

Photos Capture Melting Splendor of Alaska's Glaciers