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The solar system was okay back when Britney really was virgin . . . |
Posted on 01/23/2007 10:24:01 AM PST by Moseley
Global Warming on Pluto Puzzles Scientists By Robert Roy Britt Senior Science Writer posted: 09 October 2002 01:25 p.m. ET
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.
Do you mean between light/heat peak input and temperature peak?
As long as Pluto is close enough that the net input of heat is positive, it will continue to warm, even though the *rate* of warming is decreasing.
What a coinkydink!
Yes, Pluto got "Plutoed."
The global warming party line is that they certainly have taken into account the very slight change in solar energy output (only about 0.1%), and it can only account for a small fraction of the observed warming. (Your graph is of sunspot numbers, not actual solar output; the sun puts out slightly more energy during sunspot maximums, and as your graph shows, these have been higher in recent decades.)
Wow! They have SUVs and cow farts on Mars too?
You are correct, though Mideast oil is part of capitalism. Just ask the greenies who want to shut down oil companies.
Are you saying you don't want warming on Uranus?
Hey guys, are you listening to yourselves? Dear God, to what lengths are you willing to go to twist and corrupt the truth? People who are willing to pervert the truth in this way demonstrate that they are pursuing some goals other than truth.
As several of you have pointed out, there is a thermal lag of approximately 30 to 45 days on Earth. The earth is far more massive than Pluto, meaning that far MORE energy is required to warm the earth. Yet only 30 to 45 days is needed for the time lag / thermal lag effect on Earth.
One of the major reasons there is a thermal lag is that the ocean holds the heat and takes time to warm up. THERE IS NO OCEAN on Pluto. There is also relatively little atmosphere on Pluto to hold teh heat and retard temperature changes.
Therefore, it would not take 14 years for Pluto to react to the heat of the sun. It would take only a few months.
I'd say something is causing all the warming. And somehow I doubt its SUV's and cow farts.
"Are you saying you don't want warming on Uranus?"
No, because then I'd have to see the doctor.
"And so it begins."
But they assume it is negligible. The first papers using the real figures were out last year - which show A) That the direct solar affect is between 10% and 40% of observed, and B) that they don't have long enough of a datastring (barely 2 solar half-cycles) to say that with much confidence.
I hope the scientific estimates of when the sun would blaze out and consume the earth weren't off by this much.
That's hemisphere-related due to seasons from the tilt of our axis, but it illustrates the principal that as long as the sun inputs more than the planet outputs, even if less than what it was doing previously, there is still warming. For the overall it's also related to the length of our year. I too am dubious that the offset is 14 years for Pluto, but it is bound to be a while, since for several years the relative change in distance isn't much.
In the 60s we were astonished at how Lysenko had managed to pervert (for the Soviet state) genetics. And, today the same thing is happening.
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The solar system was okay back when Britney really was virgin . . . |
Given that the Little Ice Age occurred between the MWP and now, it is unsurprising that the time since the LIA has been a general, if broken, warming trend. Even the 20th century had notable breaks in the warming trend.
The much lower 10-40% came from an article published a year earlier, where Scafetta admits "I think it is important to correct the climate models so that they include reliable sensitivity to solar activity.Once that is done, then it will be possible to better understand what has happened during the past hundred years."
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