From the mailbag from Pleiades:
The Cassini spacecraft, a cooperative project between NASA, ESA and Agenzia Spaziale Italiana, has indicated that Saturn's ring system has its own atmosphere.Way cool. Now, to wait for the Hoagland version of this story. :)
Data from the Cassini spacecraft indicate that Saturn's majestic ring system has its own atmosphere, separate from that of the planet, according to an August 17 press release from the European Space Agency (ESA).
The Cassini-Huygens mission is a cooperative project of NASA, ESA and Agenzia Spaziale Italiana, the Italian space agency.
During its close fly-bys of Saturn’s ring system, Cassini's instruments showed that the environment around the rings is an atmosphere composed mainly of oxygen molecules, similar to the atmospheres of Jupiter's moons Europa and Ganymede.
“As water comes off the rings, it is split by sunlight; the resulting hydrogen and atomic oxygen are then lost, leaving molecular oxygen,” said Andrew Coates, a co-investigator for one of the instruments from University College London.
Saturn's rings are mainly water ice mixed with smaller amounts of dust and rocky matter. They are very thin – no more than 1.5 kilometers, although they are 250,000 kilometers or more in diameter.
The rings’ origin is unknown. Scientists once thought they formed at the same time as the planets, coalescing from swirling clouds of interstellar gas 4,000 million years ago. But the rings now appear to be young, perhaps only hundreds of millions of years old.
Another theory suggests that a comet flew too close to Saturn and was broken up by the planet’s tidal forces. Alternatively, one of Saturn's moons might have been struck by an asteroid, smashing it into the pieces that now form the rings.
The ring system is unstable and must be constantly regenerated, probably by the breakup of larger planetary bodies. The atmosphere is likely kept in place by gravitational forces and a balance between the loss and replacement of ring particles, Coates said.
Last month, mission scientists celebrated Cassini’s first year in orbit around Saturn. The spacecraft began to orbit Saturn in July 2004 after a six-year journey of more than 3 billion kilometers.
Additional information about the mission is available on both the NASA Web site and the European Space Agency Web site.
Text of the ESA press release follows:
European Space Agency
[Paris, France]
Press release, August 17, 2005
Saturn’s rings have own atmosphere
Spectrum from Cassini instruments indicating atmosphere over rings
Data from the NASA/ESA/ASI Cassini spacecraft indicate that Saturn's majestic ring system has its own atmosphere -- separate from that of the planet itself.
During its close fly-bys of the ring system, instruments on Cassini have been able to determine that the environment around the rings is like an atmosphere, composed principally of molecular oxygen.
This atmosphere is very similar to that of Jupiter's moons Europa and Ganymede.
The finding was made by two instruments on Cassini, both of which have European involvement: the Ion and Neutral Mass Spectrometer (INMS) has co-investigators from USA and Germany, and the Cassini Plasma Spectrometer (CAPS) instrument has co-investigators from US, Finland, Hungary, France, Norway and UK.
Saturn's rings consist largely of water ice mixed with smaller amounts of dust and rocky matter. They are extraordinarily thin: though they are 250 000 kilometres or more in diameter they are no more than 1.5 kilometres thick.
Despite their impressive appearance, there is very little material in the rings -- if the rings were compressed into a single body it would be no more than 100 kilometres across.
The origin of the rings is unknown. Scientists once thought that the rings were formed at the same time as the planets, coalescing out of swirling clouds of interstellar gas 4000 million years ago. However, the rings now appear to be young, perhaps only hundreds of millions of years old. Another theory suggests that a comet flew too close to Saturn and was broken up by tidal forces. Possibly one of Saturn's moons was struck by an asteroid smashing it to pieces that now form the rings.
Though Saturn may have had rings since it formed, the ring system is not stable and must be regenerated by ongoing processes, probably the break-up of larger satellites.
Water molecules are first driven off the ring particles by solar ultraviolet light. They are then split into hydrogen, and molecular and atomic oxygen, by photodissocation. The hydrogen gas is lost to space, the atomic oxygen and any remaining water are frozen back into the ring material due to the low temperatures, and this leaves behind a concentration of oxygen molecules.
Dr Andrew Coates, co-investigator for CAPS, from the Mullard Space Science Laboratory (MSSL) at University College London, said: "As water comes off the rings, it is split by sunlight; the resulting hydrogen and atomic oxygen are then lost, leaving molecular oxygen.
"The INMS sees the neutral oxygen gas, CAPS sees molecular oxygen ions and an ‘electron view’ of the rings. These represent the ionised products of that oxygen and some additional electrons driven off the rings by sunlight."
Dr Coates said the ring atmosphere was probably kept in check by gravitational forces and a balance between loss of material from the ring system and a re-supply of material from the ring particles. Last month, Cassini-Huygens mission scientists celebrated the spacecraft's first year in orbit around Saturn. Cassini performed its Saturn Orbit Insertion (SOI) on 1 July 2004 after its six-year journey to the ringed planet, travelling over three thousand million kilometres.
Randy Implodes
Randy Johnson has been having a bitch of a season in the Big Apple, where expectations run about as high as King Kong climbed. It's just the nature of that city and its denizens. he has alternatively been referred to as 'The Big Disappointment' or 'The Big Uselss' , or 'The Mediocre Unit' amongst other nasty epithets instead of his famous 'Big Unit' tag. The press has been particularly pointed with Randy Johnson since his snarling arrival. It's like he didn't throw that perfect game last year.
They (as in the Yankee brass) say that it takes a long time for the superstars to acclimate to playing in NYC, so I d cut some slack with the big fella', but then you have games like today.
AP - Aug 21, 6:33 pm EDTI don't know what to make of it, but Randy Johnson seems to have imploded under the weight of his own reputation.
More PhotosCHICAGO (AP) -- Randy Johnson sat by his locker and shook his head as he searched for reasons, an effort that was futile.
A dazed and frustrated Johnson allowed home runs to three consecutive batters for the first time in his major league career and four in all during the fourth inning, and the Chicago White Sox beat the New York Yankees 6-2 Sunday to stop a seven-game losing streak.
``I felt great,'' said Johnson, who allowed the homers in a 16-pitch span. ``The velocity was there.''
But afterward, he felt miserable.
Given a 1-0 lead, Johnson allowed consecutive solo homers to Tadahito Iguchi, Aaron Rowand and Paul Konerko with one out in the fourth and, after singles by Jermaine Dye and Juan Uribe, a three-run shot to Chris Widger.
Johnson (11-8) has allowed 29 homers, the most in the American League and second in the major leagues behind Cincinnati's Eric Milton (35). The most Johnson has allowed in a season was 30 with Arizona in 1999.
The Big Unit, who missed a start earlier this month because of a bad back, allowed 10 hits, struck out eight and walked none in his fourth complete game this season. His ERA rose to 4.34, but both Johnson and manager Joe Torre said he pitched well.
``His stuff was good,'' Torre said. ``He's going to win games pitching like that.''
It was just the second time in his career Johnson allowed four home runs in a start, according to the Elias Sports Bureau. The other was on June 20, 1999, for Arizona against Atlanta.
Scott Sanderson and Catfish Hunter were the only other Yankees pitchers to allow four homers in an inning.
Chicago tied a franchise record by hitting four in an inning for the third time, the first since May 3, 2000, against Toronto.
``The energy was good today early,'' Konerko said. ``I knew we'd be in the game. I hope guys realize that we can't wait for good things to happen and then have energy. You've got to come with it first, and then good things follow.''
Former-Yankee Jose Contreras (8-7) allowed two runs -- one earned-- and 11 hits, and matched his career-high by pitching eight innings. He struck out five and walked none.
"We got 11 hits off of him, so we had some opportunities,'' Torre said. ``It looked like the right-handers were having better swings than the left-handers. We really never had him on the ropes. He had a great splitter, and it looked like that was what was getting the left-handed hitters. They just couldn't identify it and he was getting a lot of swings and misses.''
After allowing a leadoff single to Pablo Ozuna in the first, Johnson retired nine straight batters before a White Sox offense that scored two runs in its previous three games came to life.
Iguchi homered to right on a 2-0 pitch, and Rowand homered to right after fouling off a 2-2 pitch to put Chicago ahead.
Konerko, who missed the first two games of the series with a strained lower back, fell behind 0-2 before sending a drive to left for his 32nd homer.
It was the seventh time in franchise history the White Sox hit three consecutive homers. Johnson was the first Yankees pitcher to give up three straight since Bill Fulton in the eighth inning against Minnesota on Sept. 12, 1987.
After the singles by Dye and Uribe, Widger hit his fourth home run of the season, connecting on a high 1-2 pitch that Johnson wanted him to chase.
``How do you explain something like that?'' Johnson said. ``It's the one thing that I'll walk away from this game not really understanding.''
Johnson is 0-2 with two no-decisions since pitching eight scoreless innings against Minnesota on July 26.
``I felt very comfortable watching Randy pitch,'' Torre said. ``The first three innings it looked like he was having an easy time locating the ball. But that inning, it seemed like the more pitches he tried to make, the less success he had trying to locate them.''
Today, he gave up 4 homeruns in an inning; three of them consecutive; giving up 6 runs in total in a complete game 6-2 loss. In other words, had he not had that one bad inning, he had a shutout going. Let's rephrase this another way. The difference between an ERA of 0.00 and 9.00 was made up of 6 pitches. As in HR, HR, HR, single, single, HR. Well of course, that would undo 17 innings, let alone 8 good innings of shut-out ball. This just does not look like a Yankee team headed for the play-offs.
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