linuxgeek
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astronomy & space stuff
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gypsywitch
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You know that Orion was Isiris to the Egyptians, right?
linuxgeek
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gypsywitch said:
No, didn't know that specific association. Have seen that the primary pyramids are layed out across the Egyptian land scape in the same pattern as the primary stars of Orion. If I remember correctly, a few of the "ports" in the large pyramids align with stars of Orion at specific times of the year.
gypsywitch
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Ahh yes... and the vent tube theory for the soul's passage out from the tomb to fly between the two stars in Osiris' belt when the vent pointed in the right direction. The great gate to the heavens perhaps?
Maybe the builders just needed air? Nahh... there seems to be more to it than that.
Maybe the builders just needed air? Nahh... there seems to be more to it than that.
linuxgeek
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There are those who believe that the pyramids built in the northern hemisphere are actually some kind of tracking system for ships from outer space. If I recall correctly, the pyramids of the Egyptians & the Mayans were build practically on the same degree latitude and the big pyramids are amoung the few man made objects which are recognizable from orbit.
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Rover hits one-year mark on Mars
By Tariq Malik
SPACE.com
Monday, January 3, 2005 Posted: 4:04 PM EST (2104 GMT)
Sitting on the hill of an alien world millions of miles from home, a hardy NASA robot celebrates an anniversary Monday -- one year on the planet Mars.
The Mars rover Spirit has come a long way since it hurtled down through the planet's atmosphere and came to a bouncy, airbag-protected stop at Gusev Crater on January 3, 2004.
It has survived more than four times its initial 90-day mission, driven miles across the Martian landscape and weathered a red planet winter only to scale hills for its human handlers.
A live webcast of NASA's One Year on Mars celebration begins Monday at 1:00 p.m. ET. NASA will commemorate Spirit's first year with a full day of programming, news conferences and even a rover birthday cake on NASA TV also beginning at 1:00 p.m. ET (1800 GMT) today.
Spirit continues to return data from the Columbia Hills, a region more than two miles (3.2 kilometers) from its Gusev Crater landing site. Scouring those hills has given Spirit -- and researchers -- more evidence that water shaped Mars' past.
Meanwhile, on the other side of Mars at Meridiani Planum, Spirit's robotic twin Opportunity is studying its own heat shield while it seeks to dig up more details on the area's watery past.
"It's astonishing to me how well it's going," said Steve Squyres, principal investigator for the Mars Exploration Rover (MER) project from Cornell University, of the mission in a telephone interview. "They're tough machines built by a fantastic team."
A software problem dogged Spirit in the early weeks of its mission when it fell silent for a period, but engineers were able to work through the glitch and resume the rover's science mission.
"That was waiting to bite us," Squyres said of the glitch, which involved Spirit's flash memory and required updated software to fix. "If Opportunity had landed first, it would have had the same problem."
Spirit has experienced other quirks, such as a finicky wheel that has left it dependent on only five of its six wheels to rove about Mars. But the glitch has not prevented rover from slowly making its way up "Husband Hill" in the Columbia Hills toward a vantage that researchers hope will give it a glimpse into a nearby valley.
"Spirit is our tough, hardworking robot," Squyres said, adding the rover is scratched and dusty. "Opportunity looks like she just came off the showroom floor, clean and pretty."
Squyres and other mission team members have become so adept at handling Spirit and Opportunity from Earth, they no longer need to congregate at NASA's Jet Propulsion Laboratory (JPL) to plan each moment of each rover's day. Instead, telephone and video conferences allow researchers to operate the rovers remotely.
"From an engineering standpoint, you really have to tip your hat," JPL's Matt Golombek told SPACE.com. "These rovers were designed for a lifetime of three months and now it's not clear when they're going to stop."
Rover hits one-year mark on Mars
By Tariq Malik
SPACE.com
Monday, January 3, 2005 Posted: 4:04 PM EST (2104 GMT)
Sitting on the hill of an alien world millions of miles from home, a hardy NASA robot celebrates an anniversary Monday -- one year on the planet Mars.
The Mars rover Spirit has come a long way since it hurtled down through the planet's atmosphere and came to a bouncy, airbag-protected stop at Gusev Crater on January 3, 2004.
It has survived more than four times its initial 90-day mission, driven miles across the Martian landscape and weathered a red planet winter only to scale hills for its human handlers.
A live webcast of NASA's One Year on Mars celebration begins Monday at 1:00 p.m. ET. NASA will commemorate Spirit's first year with a full day of programming, news conferences and even a rover birthday cake on NASA TV also beginning at 1:00 p.m. ET (1800 GMT) today.
Spirit continues to return data from the Columbia Hills, a region more than two miles (3.2 kilometers) from its Gusev Crater landing site. Scouring those hills has given Spirit -- and researchers -- more evidence that water shaped Mars' past.
Meanwhile, on the other side of Mars at Meridiani Planum, Spirit's robotic twin Opportunity is studying its own heat shield while it seeks to dig up more details on the area's watery past.
"It's astonishing to me how well it's going," said Steve Squyres, principal investigator for the Mars Exploration Rover (MER) project from Cornell University, of the mission in a telephone interview. "They're tough machines built by a fantastic team."
A software problem dogged Spirit in the early weeks of its mission when it fell silent for a period, but engineers were able to work through the glitch and resume the rover's science mission.
"That was waiting to bite us," Squyres said of the glitch, which involved Spirit's flash memory and required updated software to fix. "If Opportunity had landed first, it would have had the same problem."
Spirit has experienced other quirks, such as a finicky wheel that has left it dependent on only five of its six wheels to rove about Mars. But the glitch has not prevented rover from slowly making its way up "Husband Hill" in the Columbia Hills toward a vantage that researchers hope will give it a glimpse into a nearby valley.
"Spirit is our tough, hardworking robot," Squyres said, adding the rover is scratched and dusty. "Opportunity looks like she just came off the showroom floor, clean and pretty."
Squyres and other mission team members have become so adept at handling Spirit and Opportunity from Earth, they no longer need to congregate at NASA's Jet Propulsion Laboratory (JPL) to plan each moment of each rover's day. Instead, telephone and video conferences allow researchers to operate the rovers remotely.
"From an engineering standpoint, you really have to tip your hat," JPL's Matt Golombek told SPACE.com. "These rovers were designed for a lifetime of three months and now it's not clear when they're going to stop."
linuxgeek
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DARK FILAMENT: Astronomers are monitoring a gigantic dark filament on the sun. Filaments are ribbons of relatively cool gas held suspended above the sun's surface by magnetic forces. This one stretches more than 250,000 miles from end to end--about the distance from Earth to the Moon.
http://www.spaceweather.com/swpod2005/04jan05/strieber1_strip.jpg
http://www.spaceweather.com/swpod2005/04jan05/strieber1_strip.jpg
linuxgeek
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Deep Impact Set For Launch But Scientists Must Wait Six Months For Main Event
by Lori Stiles
Tucson AZ (SPX) Jan 04, 2005
The scientist who wrote the book on planetary impact cratering will join NASA and other university researchers at Kennedy Space Center, Fla., to watch the launch of Deep Impact this month.
If all goes as planned, Deep Impact will become the first mission to slam into a comet, giving astronomers worldwide something far better than any other fireworks show on July 4, 2005 the first look inside a comet at the most primitive material left in the solar system.
"The idea is that the best way to find what's inside a comet is to blast a hole in it," University of Arizona Regents' Professor and Deep Impact science team member H. Jay Melosh said. "Other comet-rendezvous missions have proposed sampling less than a foot into the upper surface. But that doesn't get at the ices in the interior, which scientists believe are early solar system materials that have been kept in the deep freeze for the past 4.5 billion years."
Melosh has done more than any other single scientist to explain how impact cratering has shaped the terrestrial planets, including Earth. His 1989 book on the topic is still the universal reference for scholars, expert or novice. Melosh's research interests relate to the origin and evolution of the early solar system. Deep Impact could add chapters to that story.
NASA's Deep Impact spacecraft is planned for liftoff Jan. 12, 2005, and no later than Jan. 28, to reach comet Tempel 1 beyond the orbit of Mars on July 4. During the rendezvous, Deep Impact will deploy an 820 pound (372 kilogram) copper probe into the comet at about 23,000 mph (37,000 kph), or about a hundred times faster than a bullet fired from a .22 caliber gun.
The probe carries a digital camera that will send images in real time back to the spacecraft as the projectile hurls through dust and debris toward the comet.
Powerful cameras and a spectrometer on the parent spacecraft, flying about 300 miles (500 kilometers) away, will capture what happens on impact. The instruments will follow events for about 10 minutes after the collision, until the spacecraft goes into shield mode to survive flight through the comet's dusty orbital plane, where it will be blasted by buckshot-to-gumball-sized particles.
"The impact may form a crater about the size of a football field and deep enough to swallow a 10-story building. The deeper the better, " Melosh said. "We're hoping to see the crater explosion and the ejecta plume. We'll get some idea of the strength of the interior of the comet as the crater grows and ejecta is blown out." The comet nucleus could be hard, Melosh said -- or fluffy as a bowl of cornflakes.
Impressive as the impact will be, it's only a minor hit as far as Tempel 1 is concerned, Melosh said. The mass of the copper impactor is miniscule compared the mass of the five-to-six-mile-long comet. An analogy would be a smash-up between an 18-wheeler and an armadillo crossing the road, or even a mosquito smashing into a windshield, he noted.
Scientists plan to get spectra that will tell them what molecules make up the comet ices.
"There'll be a flash of volatiles that we may see with the spectrometer in the early stage of impact, and that astronomers will see from the ground and with space-based telescopes like Hubble, Chandra and Spitzer."
A global network of professional and amateur astronomers will observe the comet for the next few days as it brightens after impact.
During mission design, Melosh carefully calculated the abundances of "critical" elements scientists might expect to see vaporize on impact. Critical elements are those which scientists want to measure because they are important in early solar system processes. Melosh also modeled how much mass of each of the different elements would be vaporized on impact so scientists can know how much vaporized material comes from the comet and how much from the spacecraft.
The Deep Impact probe is made mostly of copper because "copper is an element that no geochemist or cosmochemist trying to work out the origin of the solar system cares about. It's not characteristic of any particular solar system process," Melosh said.
University of Maryland astronomy professor Michael A'Hearn is principal investigator for Deep Impact. He leads the mission from the University of Maryland, College Park. Kitt Peak National Observatory Astronomer Emeritus Michael Belton of Belton Space Exploration Initiatives, Tucson, is another member of the Deep Impact science team.
Ball Aerospace & Technologies in Boulder, Colo., built NASA's Deep Impact spacecraft. It was shipped to Florida in October for final launch preparations. NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the Deep Impact project for the Science Mission Directorate at NASA Headquarters. Deep Impact is a mission in NASA's Discovery program of moderately priced solar system exploration missions.
Deep Impact Set For Launch But Scientists Must Wait Six Months For Main Event
by Lori Stiles
Tucson AZ (SPX) Jan 04, 2005
The scientist who wrote the book on planetary impact cratering will join NASA and other university researchers at Kennedy Space Center, Fla., to watch the launch of Deep Impact this month.
If all goes as planned, Deep Impact will become the first mission to slam into a comet, giving astronomers worldwide something far better than any other fireworks show on July 4, 2005 the first look inside a comet at the most primitive material left in the solar system.
"The idea is that the best way to find what's inside a comet is to blast a hole in it," University of Arizona Regents' Professor and Deep Impact science team member H. Jay Melosh said. "Other comet-rendezvous missions have proposed sampling less than a foot into the upper surface. But that doesn't get at the ices in the interior, which scientists believe are early solar system materials that have been kept in the deep freeze for the past 4.5 billion years."
Melosh has done more than any other single scientist to explain how impact cratering has shaped the terrestrial planets, including Earth. His 1989 book on the topic is still the universal reference for scholars, expert or novice. Melosh's research interests relate to the origin and evolution of the early solar system. Deep Impact could add chapters to that story.
NASA's Deep Impact spacecraft is planned for liftoff Jan. 12, 2005, and no later than Jan. 28, to reach comet Tempel 1 beyond the orbit of Mars on July 4. During the rendezvous, Deep Impact will deploy an 820 pound (372 kilogram) copper probe into the comet at about 23,000 mph (37,000 kph), or about a hundred times faster than a bullet fired from a .22 caliber gun.
The probe carries a digital camera that will send images in real time back to the spacecraft as the projectile hurls through dust and debris toward the comet.
Powerful cameras and a spectrometer on the parent spacecraft, flying about 300 miles (500 kilometers) away, will capture what happens on impact. The instruments will follow events for about 10 minutes after the collision, until the spacecraft goes into shield mode to survive flight through the comet's dusty orbital plane, where it will be blasted by buckshot-to-gumball-sized particles.
"The impact may form a crater about the size of a football field and deep enough to swallow a 10-story building. The deeper the better, " Melosh said. "We're hoping to see the crater explosion and the ejecta plume. We'll get some idea of the strength of the interior of the comet as the crater grows and ejecta is blown out." The comet nucleus could be hard, Melosh said -- or fluffy as a bowl of cornflakes.
Impressive as the impact will be, it's only a minor hit as far as Tempel 1 is concerned, Melosh said. The mass of the copper impactor is miniscule compared the mass of the five-to-six-mile-long comet. An analogy would be a smash-up between an 18-wheeler and an armadillo crossing the road, or even a mosquito smashing into a windshield, he noted.
Scientists plan to get spectra that will tell them what molecules make up the comet ices.
"There'll be a flash of volatiles that we may see with the spectrometer in the early stage of impact, and that astronomers will see from the ground and with space-based telescopes like Hubble, Chandra and Spitzer."
A global network of professional and amateur astronomers will observe the comet for the next few days as it brightens after impact.
During mission design, Melosh carefully calculated the abundances of "critical" elements scientists might expect to see vaporize on impact. Critical elements are those which scientists want to measure because they are important in early solar system processes. Melosh also modeled how much mass of each of the different elements would be vaporized on impact so scientists can know how much vaporized material comes from the comet and how much from the spacecraft.
The Deep Impact probe is made mostly of copper because "copper is an element that no geochemist or cosmochemist trying to work out the origin of the solar system cares about. It's not characteristic of any particular solar system process," Melosh said.
University of Maryland astronomy professor Michael A'Hearn is principal investigator for Deep Impact. He leads the mission from the University of Maryland, College Park. Kitt Peak National Observatory Astronomer Emeritus Michael Belton of Belton Space Exploration Initiatives, Tucson, is another member of the Deep Impact science team.
Ball Aerospace & Technologies in Boulder, Colo., built NASA's Deep Impact spacecraft. It was shipped to Florida in October for final launch preparations. NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the Deep Impact project for the Science Mission Directorate at NASA Headquarters. Deep Impact is a mission in NASA's Discovery program of moderately priced solar system exploration missions.
linuxgeek
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gypsywitch
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great thead
Wonder if they intended to build more to make the constellation complete?
Its no wonder that ancient religions were created based on the seasons and the stars. It must have seemed so grand and powerful back then.
With all our science removing the mystery, we're still wondering how it all just hangs there as a universe.
Wonder if they intended to build more to make the constellation complete?
Its no wonder that ancient religions were created based on the seasons and the stars. It must have seemed so grand and powerful back then.
With all our science removing the mystery, we're still wondering how it all just hangs there as a universe.
G
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Re: great thead
I'm not so sure it's a matter of science removing any mystery as it is of light pollution. When I was a child I liked to look at the stars. I had some light pollution nearby, but not a lot. I could actually see different constellations. And then I got older and lived in a place where I was lucky if I could see more than 3 or 4 stars at night. Then I moved to a place where I was lucky if I could see one star at night. By that point I had stopped looking because there wasn't anything I'd be able to see. And then I went to Mexico, where no one had any electricity. And even with a city not so far away I could see myriads of stars, and I was awestruck. Hell, I could even see part of the Milky Way--that's how little light pollution there was. And the first time I saw that I remember thinking, "So this is what people saw..." And that was with a city in the next valley, so there was still some light pollution. I can't imagine what it would have looked like with no light pollution.
gypsywitch said:
I'm not so sure it's a matter of science removing any mystery as it is of light pollution. When I was a child I liked to look at the stars. I had some light pollution nearby, but not a lot. I could actually see different constellations. And then I got older and lived in a place where I was lucky if I could see more than 3 or 4 stars at night. Then I moved to a place where I was lucky if I could see one star at night. By that point I had stopped looking because there wasn't anything I'd be able to see. And then I went to Mexico, where no one had any electricity. And even with a city not so far away I could see myriads of stars, and I was awestruck. Hell, I could even see part of the Milky Way--that's how little light pollution there was. And the first time I saw that I remember thinking, "So this is what people saw..." And that was with a city in the next valley, so there was still some light pollution. I can't imagine what it would have looked like with no light pollution.
linuxgeek
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Icebergs in New Zealand waters for first time in 57 years
WELLINGTON (AFP) Jan 06, 2005
New Zealanders complaining about unseasonal summer rain in recent weeks have received proof of changing climatic conditions after icebergs were sighted in local waters for the first time since 1948.
The icebergs were see in the Southern Ocean, about 700 kilometresmiles) southeast of the South Island, the National Institute of Water and Atmospheric Research (NIWA) said Thursday.
They were a hazard to all shipping, including yachts participating in the Vendeeglobe solo round-the-world race, officials said.
The Vendeeglobe website has issued a warning to competitors after one sailor sustained minor damage to his boat when he hit an iceberg just before Christmas.
NIWA scientist Lionel Carter said 15 icebergs, some up to three kilometres wide, have been recorded.
"In 30 years of working for NIWA, this is the first time I have recorded sightings of icebergs in New Zealand waters," Carter said.
Previous reportings were in the 1890s, early 1920s, 1930s and in 1948.
In 1931 icebergs were seen as far north as near Dunedin in the South Island.
He said it was too soon to blame this flotilla of ice on global warming, although the coincidence of large collapses of the Antarctic ice shelves with a rapidly changing climate could not be dismissed.
The icebergs were expected to drift away towards South America.
Icebergs in New Zealand waters for first time in 57 years
WELLINGTON (AFP) Jan 06, 2005
New Zealanders complaining about unseasonal summer rain in recent weeks have received proof of changing climatic conditions after icebergs were sighted in local waters for the first time since 1948.
The icebergs were see in the Southern Ocean, about 700 kilometresmiles) southeast of the South Island, the National Institute of Water and Atmospheric Research (NIWA) said Thursday.
They were a hazard to all shipping, including yachts participating in the Vendeeglobe solo round-the-world race, officials said.
The Vendeeglobe website has issued a warning to competitors after one sailor sustained minor damage to his boat when he hit an iceberg just before Christmas.
NIWA scientist Lionel Carter said 15 icebergs, some up to three kilometres wide, have been recorded.
"In 30 years of working for NIWA, this is the first time I have recorded sightings of icebergs in New Zealand waters," Carter said.
Previous reportings were in the 1890s, early 1920s, 1930s and in 1948.
In 1931 icebergs were seen as far north as near Dunedin in the South Island.
He said it was too soon to blame this flotilla of ice on global warming, although the coincidence of large collapses of the Antarctic ice shelves with a rapidly changing climate could not be dismissed.
The icebergs were expected to drift away towards South America.
gypsywitch
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I remember camping as a kid and feeling really creeped out when laying in a field at night on a mountainside just because it was so RIGHT THERE in my face. It was like flying in a way. Sorta scary but fun.
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gypsywitch said:
Ever see any satellites go by? The first time I saw them I asked my father what they were. They were much too slow to be meteors, didn't blink like planes. When he told me they were satellites I was so surprised that I didn't believe him at first. I didn't think anyone would be able to see satellites from the earth. I thought they would be too small to see from that far away. I remember being amazed at all the satellites I've seen that way, too. We must have an awful lot of junk orbiting our planet because you don't have to wait very long to spot one.
I know what feeling you're talking about. It's the feeling you get when you're lying on your back and staring at the sky, and you begin to feel almost as if you're looking "down" into it. And for a few moments you are afraid that you will fall into it.
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gypsywitch
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YEA! Gosh it was so strange too! Satellites... wow.
I get that cosmic tripper thing going on where I feel like I'm being pulled out of my body.
Hawaii is especially good for that.
I get that cosmic tripper thing going on where I feel like I'm being pulled out of my body.
Hawaii is especially good for that.
G
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gypsywitch said:
I bet any island more or less by itself is good for that. Assuming, of course, there's not a lot of light pollution coming from the island itself. I suppose anywhere that scientists put an observatory is a good place to go, as they try to put them in the areas with the least amount of light pollution and atmospheric disturbance.
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Astronomers identify trio of supergiants
SAN DIEGO, California (Reuters) -- A trio of supergiants -- red, cool, bright stars at the end of their lives -- may be the biggest stars ever identified, astronomers reported on Monday.
All three have diameters of more than 1 billion miles (km), or 1,500 times the sun's girth. If they were in the same location as the sun, they would completely engulf Earth and their outer layers would extend to a point between the orbits of Jupiter and Saturn.
The big three dwarf even Betelgeuse, a well-known supergiant and the brightest star in the constellation Orion, the team of scientists said in research presented at the annual meeting of the American Astronomical Society meeting in San Diego.
They also are slightly bigger than the previous champion, known as Herschel's "Garnet Star."
Determining their size was more a matter of computer modeling than telescope observing, said one of the researchers, Philip Massey.
An international team of astronomers, including Massey, looked at a field of 74 supergiant stars to try to learn more about them. The scientists knew the stars' distance from Earth, and they knew how bright they were, but they didn't know just how cool they were.
In the case of stellar temperatures, cool is a relative term. These stars are around 5,600 degrees Fahrenheit (3,100 degrees Celsius). The sun is nearly 10,000 degrees F (5,500 degrees C) and the hottest known stars are more than 90,000 degrees F (50,000 degrees C).
Knowing the temperature was important, Massey said, because a fundamental law of stellar physics holds that a star's brightness is proportional to its temperature and size. By knowing two of these numbers, scientists could find out the third with precision.
The team used new computer models that have improved data on molecules in the outer layers of these big stars, and found that in fact the trio were about 10 percent warmer than researchers had expected. They were also able to calculate their size, Massey said in a telephone interview from Flagstaff, Arizona, where he works at Lowell Observatory.
"I think the interesting aspect of this is that it tells us the extreme that normal stars can become, how large a normal star of any kind can ever become," Massey said.
All the stars in the study were normal stars, that is, none were two-star pairs known as binaries, whose parameters could be different.
Will this ever happen to our sun? In a word, no.
The sun simply lacks the mass to become a red supergiant, Massey said.
The three big supergiant stars are: KW Sagitarii, which is 9,800 light-years from Earth; V354 Cephei, at 9,000 light-years away; and KY Cygni, 5,200 light-years away.
A light-year is about 6 trillion miles (10 trillion km), the distance light travels in a year.
Astronomers identify trio of supergiants
SAN DIEGO, California (Reuters) -- A trio of supergiants -- red, cool, bright stars at the end of their lives -- may be the biggest stars ever identified, astronomers reported on Monday.
All three have diameters of more than 1 billion miles (km), or 1,500 times the sun's girth. If they were in the same location as the sun, they would completely engulf Earth and their outer layers would extend to a point between the orbits of Jupiter and Saturn.
The big three dwarf even Betelgeuse, a well-known supergiant and the brightest star in the constellation Orion, the team of scientists said in research presented at the annual meeting of the American Astronomical Society meeting in San Diego.
They also are slightly bigger than the previous champion, known as Herschel's "Garnet Star."
Determining their size was more a matter of computer modeling than telescope observing, said one of the researchers, Philip Massey.
An international team of astronomers, including Massey, looked at a field of 74 supergiant stars to try to learn more about them. The scientists knew the stars' distance from Earth, and they knew how bright they were, but they didn't know just how cool they were.
In the case of stellar temperatures, cool is a relative term. These stars are around 5,600 degrees Fahrenheit (3,100 degrees Celsius). The sun is nearly 10,000 degrees F (5,500 degrees C) and the hottest known stars are more than 90,000 degrees F (50,000 degrees C).
Knowing the temperature was important, Massey said, because a fundamental law of stellar physics holds that a star's brightness is proportional to its temperature and size. By knowing two of these numbers, scientists could find out the third with precision.
The team used new computer models that have improved data on molecules in the outer layers of these big stars, and found that in fact the trio were about 10 percent warmer than researchers had expected. They were also able to calculate their size, Massey said in a telephone interview from Flagstaff, Arizona, where he works at Lowell Observatory.
"I think the interesting aspect of this is that it tells us the extreme that normal stars can become, how large a normal star of any kind can ever become," Massey said.
All the stars in the study were normal stars, that is, none were two-star pairs known as binaries, whose parameters could be different.
Will this ever happen to our sun? In a word, no.
The sun simply lacks the mass to become a red supergiant, Massey said.
The three big supergiant stars are: KW Sagitarii, which is 9,800 light-years from Earth; V354 Cephei, at 9,000 light-years away; and KY Cygni, 5,200 light-years away.
A light-year is about 6 trillion miles (10 trillion km), the distance light travels in a year.
G
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Re: Re: Re: great thead
That's sounding about right. It's become a rare treat to see much more than a handful of stars at once.
I remember my astronomy professor making an interesting comment about light pollution. He said that life has adapted and evolved mostly in environments where it has been exposed to differences between daylight and nighttime. He said he's often wondered how so much artificial lighting is/will affect people and other creatures over time. I always thought that was an interesting thing to ponder.
The Mutt said:
That's sounding about right. It's become a rare treat to see much more than a handful of stars at once.
I remember my astronomy professor making an interesting comment about light pollution. He said that life has adapted and evolved mostly in environments where it has been exposed to differences between daylight and nighttime. He said he's often wondered how so much artificial lighting is/will affect people and other creatures over time. I always thought that was an interesting thing to ponder.
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NASA Details Earthquake Effects on the Earth
January 10, 2005
NASA scientists using data from the Indonesian earthquake calculated it affected Earth's rotation, decreased the length of day, slightly changed the planet's shape, and shifted the North Pole by centimeters. The earthquake that created the huge tsunami also changed the Earth's rotation.
Dr. Richard Gross of NASA's Jet Propulsion Laboratory, Pasadena, Calif., and Dr. Benjamin Fong Chao, of NASA's Goddard Space Flight Center, Greenbelt, Md., said all earthquakes have some affect on Earth's rotation. It's just they are usually barely noticeable.
"Any worldly event that involves the movement of mass affects the Earth's rotation, from seasonal weather down to driving a car," Chao said.
Gross and Chao have been routinely calculating earthquakes' effects in changing the Earth's rotation in both length-of- day as well as changes in Earth's gravitational field. They also study changes in polar motion that is shifting the North Pole. The "mean North pole" was shifted by about 2.5 centimeters (1 inch) in the direction of 145 degrees East Longitude. This shift east is continuing a long-term seismic trend identified in previous studies.
They also found the earthquake decreased the length of day by 2.68 microseconds. Physically this is like a spinning skater drawing arms closer to the body resulting in a faster spin. The quake also affected the Earth's shape. They found Earth's oblateness (flattening on the top and bulging at the equator) decreased by a small amount. It decreased about one part in 10 billion, continuing the trend of earthquakes making Earth less oblate.
To make a comparison about the mass that was shifted as a result of the earthquake, and how it affected the Earth, Chao compares it to the great Three-Gorge reservoir of China. If filled, the gorge would hold 40 cubic kilometers (10 trillion gallons) of water. That shift of mass would increase the length of day by only 0.06 microseconds and make the Earth only very slightly more round in the middle and flat on the top. It would shift the pole position by about two centimeters (0.8 inch).
The researchers concluded the Sumatra earthquake caused a length of day change too small to detect, but it can be calculated. It also caused an oblateness change barely detectable, and a pole shift large enough to be possibly identified. They hope to detect the length of day signal and pole shift when Earth rotation data from ground based and space-borne position sensors are reviewed.
The researchers used data from the Harvard University Centroid Moment Tensor database that catalogs large earthquakes. The data is calculated in a set of formulas, and the results are reported and updated on a NASA Web site.
The massive earthquake off the west coast of Indonesia on December 26, 2004, registered a magnitude of nine on the new "moment" scale (modified Richter scale) that indicates the size of earthquakes. It was the fourth largest earthquake in one hundred years and largest since the 1964 Prince William Sound, Alaska earthquake.
The devastating mega thrust earthquake occurred as a result of the India and Burma plates coming together. It was caused by the release of stresses that developed as the India plate slid beneath the overriding Burma plate. The fault dislocation, or earthquake, consisted of a downward sliding of one plate relative to the overlying plate. The net effect was a slightly more compact Earth. The India plate began its descent into the mantle at the Sunda trench that lies west of the earthquake's epicenter. For information and images on the Web, visit:
http://www.nasa.gov/vision/earth/lookingatearth/indonesia_quake.html .
For details on the Sumatra, Indonesia Earthquake, visit the USGS Internet site:
http://neic.usgs.gov/neis/bulletin/neic_slav_ts.html .
For information about NASA and agency programs Web, visit:
http://www.nasa.gov .
JPL is managed for NASA by the California Institute of Technology in Pasadena.
NASA Details Earthquake Effects on the Earth
January 10, 2005
NASA scientists using data from the Indonesian earthquake calculated it affected Earth's rotation, decreased the length of day, slightly changed the planet's shape, and shifted the North Pole by centimeters. The earthquake that created the huge tsunami also changed the Earth's rotation.
Dr. Richard Gross of NASA's Jet Propulsion Laboratory, Pasadena, Calif., and Dr. Benjamin Fong Chao, of NASA's Goddard Space Flight Center, Greenbelt, Md., said all earthquakes have some affect on Earth's rotation. It's just they are usually barely noticeable.
"Any worldly event that involves the movement of mass affects the Earth's rotation, from seasonal weather down to driving a car," Chao said.
Gross and Chao have been routinely calculating earthquakes' effects in changing the Earth's rotation in both length-of- day as well as changes in Earth's gravitational field. They also study changes in polar motion that is shifting the North Pole. The "mean North pole" was shifted by about 2.5 centimeters (1 inch) in the direction of 145 degrees East Longitude. This shift east is continuing a long-term seismic trend identified in previous studies.
They also found the earthquake decreased the length of day by 2.68 microseconds. Physically this is like a spinning skater drawing arms closer to the body resulting in a faster spin. The quake also affected the Earth's shape. They found Earth's oblateness (flattening on the top and bulging at the equator) decreased by a small amount. It decreased about one part in 10 billion, continuing the trend of earthquakes making Earth less oblate.
To make a comparison about the mass that was shifted as a result of the earthquake, and how it affected the Earth, Chao compares it to the great Three-Gorge reservoir of China. If filled, the gorge would hold 40 cubic kilometers (10 trillion gallons) of water. That shift of mass would increase the length of day by only 0.06 microseconds and make the Earth only very slightly more round in the middle and flat on the top. It would shift the pole position by about two centimeters (0.8 inch).
The researchers concluded the Sumatra earthquake caused a length of day change too small to detect, but it can be calculated. It also caused an oblateness change barely detectable, and a pole shift large enough to be possibly identified. They hope to detect the length of day signal and pole shift when Earth rotation data from ground based and space-borne position sensors are reviewed.
The researchers used data from the Harvard University Centroid Moment Tensor database that catalogs large earthquakes. The data is calculated in a set of formulas, and the results are reported and updated on a NASA Web site.
The massive earthquake off the west coast of Indonesia on December 26, 2004, registered a magnitude of nine on the new "moment" scale (modified Richter scale) that indicates the size of earthquakes. It was the fourth largest earthquake in one hundred years and largest since the 1964 Prince William Sound, Alaska earthquake.
The devastating mega thrust earthquake occurred as a result of the India and Burma plates coming together. It was caused by the release of stresses that developed as the India plate slid beneath the overriding Burma plate. The fault dislocation, or earthquake, consisted of a downward sliding of one plate relative to the overlying plate. The net effect was a slightly more compact Earth. The India plate began its descent into the mantle at the Sunda trench that lies west of the earthquake's epicenter. For information and images on the Web, visit:
http://www.nasa.gov/vision/earth/lookingatearth/indonesia_quake.html .
For details on the Sumatra, Indonesia Earthquake, visit the USGS Internet site:
http://neic.usgs.gov/neis/bulletin/neic_slav_ts.html .
For information about NASA and agency programs Web, visit:
http://www.nasa.gov .
JPL is managed for NASA by the California Institute of Technology in Pasadena.
linuxgeek
Rogue Scholar
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- Feb 1, 2004
- Posts
- 32,719
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Saturn, all night long
On Thursday, January 13th, Saturn will be 750 million miles from Earth--the closest we get to the ringed planet this year.
January 12, 2005: When the sun sets on Thursday, January 13th, a golden star will rise in the east. Soaring overhead at midnight, it will be up all night long, beautiful and eye-catching.
That "star" is Saturn.
http://science.msfc.nasa.gov/headlines/y2005/images/saturn/opposition.gif
Earth and Saturn are closest together when Saturn is "at opposition." The red circle is Saturn's orbit; the blue Earth's.
January 13th is a special date for Saturn because that's when it is closest to Earth: only 750 million miles away, compared to a maximum distance of almost a billion miles. This makes the ringed planet unusually big and bright.
An astronomer would say "Saturn is at opposition" because Saturn and the sun are on opposite sides of the sky. Earth and Saturn are closest together at opposition; see the figure below. The sun, Earth and Saturn are lined up in a straight line with Earth in the middle. This happens every 13 months, approximately. The 2005 opposition of Saturn is so perfect that, if you were on Saturn, you would see Earth transiting the face of the Sun.
To find Saturn, step outside around 7:30 p.m. local time and face east. The planet is easy to see almost halfway up the sky next to Castor and Pollux in the constellation Gemini.
Got a telescope? Point it at Saturn. Even a small department-store 'scope will show the planet's rings. They are breathtaking. You might also notice a little pinprick of light near Saturn. That's Titan, Saturn's largest moon.
The European Space Agency's (ESA's) Huygens probe will attempt to land on Titan on January 14th. With hypothesized methane rain, gasoline seas, hot lightning and icy mountains, Titan could be the weirdest world in the solar system. Or not. No one knows because dense orange clouds hide the giant moon's surface. If Huygens survives its bold descent, we'll soon find out what's down there. Good luck ESA!
http://science.msfc.nasa.gov/headlines/y2005/images/saturn/skymap_north.gif
If bad weather spoils your view on January 13th, don't worry. Saturn will remain close to Earth, receding slowly, all month long. You can find it any evening in the eastern sky next to Castor and Pollux. January 23rd is especially good because the full moon will glide right past Saturn, marking its location for all to see.
Bright, golden, ringed, breathtaking: Saturn. It's worth a look.
Saturn, all night long
On Thursday, January 13th, Saturn will be 750 million miles from Earth--the closest we get to the ringed planet this year.
January 12, 2005: When the sun sets on Thursday, January 13th, a golden star will rise in the east. Soaring overhead at midnight, it will be up all night long, beautiful and eye-catching.
That "star" is Saturn.
http://science.msfc.nasa.gov/headlines/y2005/images/saturn/opposition.gif
Earth and Saturn are closest together when Saturn is "at opposition." The red circle is Saturn's orbit; the blue Earth's.
January 13th is a special date for Saturn because that's when it is closest to Earth: only 750 million miles away, compared to a maximum distance of almost a billion miles. This makes the ringed planet unusually big and bright.
An astronomer would say "Saturn is at opposition" because Saturn and the sun are on opposite sides of the sky. Earth and Saturn are closest together at opposition; see the figure below. The sun, Earth and Saturn are lined up in a straight line with Earth in the middle. This happens every 13 months, approximately. The 2005 opposition of Saturn is so perfect that, if you were on Saturn, you would see Earth transiting the face of the Sun.
To find Saturn, step outside around 7:30 p.m. local time and face east. The planet is easy to see almost halfway up the sky next to Castor and Pollux in the constellation Gemini.
Got a telescope? Point it at Saturn. Even a small department-store 'scope will show the planet's rings. They are breathtaking. You might also notice a little pinprick of light near Saturn. That's Titan, Saturn's largest moon.
The European Space Agency's (ESA's) Huygens probe will attempt to land on Titan on January 14th. With hypothesized methane rain, gasoline seas, hot lightning and icy mountains, Titan could be the weirdest world in the solar system. Or not. No one knows because dense orange clouds hide the giant moon's surface. If Huygens survives its bold descent, we'll soon find out what's down there. Good luck ESA!
http://science.msfc.nasa.gov/headlines/y2005/images/saturn/skymap_north.gif
If bad weather spoils your view on January 13th, don't worry. Saturn will remain close to Earth, receding slowly, all month long. You can find it any evening in the eastern sky next to Castor and Pollux. January 23rd is especially good because the full moon will glide right past Saturn, marking its location for all to see.
Bright, golden, ringed, breathtaking: Saturn. It's worth a look.
linuxgeek
Rogue Scholar
- Joined
- Feb 1, 2004
- Posts
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Huygens to plumb secrets of Saturn moon
By Michael Coren
CNN
(CNN) -- The Huygens probe will plunge through the orange clouds of Saturn's moon Titan Friday, offering scientists their first glimpse of the mysterious moon.
"It's going to be the most exotic place we've ever seen," said Candice Hansen, a scientist for the Cassini-Huygens mission. "We've never landed on the surface of an icy satellite. We know from our pictures that there are very different kinds of geological processes."
If all goes well, the saucer-shaped Huygens will enter the thick atmosphere of Titan Friday at about 5:13 a.m. (ET). The data should start trickling in about five hours later.
The Cassini-Huygens mission is an unprecedented $3.3-billion effort between NASA, the European Space Agency and Italy's space program to study Saturn and its 33 known moons. The two vehicles were launched together from Florida in 1997.
"The mission is to explore the entire Saturnian system in considerably greater detail than we have ever been able to do before: the atmosphere, the internal structure, the satellites, the rings, the magnetosphere," said Cassini program manager Bob Mitchell at NASA.
The Huygens probe, about the size of a Volkswagen-Beetle, has been spinning silently toward Titan since it detached from the Cassini spacecraft on December 24. Cassini will remain in orbit around Saturn until at least July 2008.
"[The Cassini-Huygens mission] will probably help answer some of the big questions that NASA has in general about origins and where we came from and where life came from," said Mitchell.
Titan's atmosphere, a murky mix of nitrogen, methane and argon, resembles Earth's before life began more than 3.8 billion years ago. Scientists think the moon may shed light on how life evolved on Earth.
Finding living organisms, however, is a remote possibility. "It is not out of the question, but it is certainly not the first place I would look," said Hansen. "It's really very cold." A lack of sunlight has put Titan into a deep-freeze. Temperatures hover around -292 F (-180 C) making liquid water scarce and hindering chemical reactions needed for organic life.
New discoveries
The mysteries of Saturn, the sixth planet from the sun, have always enticed researchers. Scientists are perplexed why Saturn, a gas-giant composed primarily of hydrogen and helium, releases more energy than it absorbs from faint sunlight. Titan is also the only moon in the solar system to retain a substantial atmosphere, one even thicker than Earth's.
The 703-pound, battery-powered probe will parachute through Titan's clouds of methane and nitrogen for two and a half hours sampling gases and capturing panoramic pictures. Soon afterward, Huygens will reach the surface. However, its landing site is still a matter of conjecture. Scientists say it could be solid, slushy or even a liquid sea of ethane and hydrocarbons.
"Those are the kinds of things that we have theories about, but we really don't have data," said Hansen.
Huygens is expected to hit the upper atmosphere 789 miles (1,270 km) above the moon at a speed of about 13,700 mph (22,000 km/h). A series of three parachutes will slow the craft to just 15 mph (24 km/h). The chutes and special insulation will protect Huygens from temperature swings and violent air currents. Strong winds -- in excess of 311 mph (500 km/h) --will buffet the craft, at times dragging Huygens sideways after its parachute is deployed.
Sensors will deduce wind speed, atmospheric pressure and the conductivity of Titan's air. Methane clouds and possibly hydrocarbon rain can be analyzed by an onboard gas chromatograph. A microphone will listen for thunder.
Three rotating cameras will snap panoramic views of the moon capturing up to 1,100 images. A radar altimeter will map Titan's topography and a special lamp will illuminate the probe's landing spot to help determine the surface composition.
Engineers say they are confident that Huygens and its suite of six sensitive instruments will survive the descent.
"From an engineering standpoint, I'm very confident in a positive outcome," said Shaun Standley, an ESA systems engineer for Huygens at the Jet Propulsion Laboratory in California. "We've been over this again and again for the last three years fine-tuning this."
As the largest and most sophisticated interplanetary vehicle ever launched, according to NASA, Cassini-Huygens has performed well on its 2.2-billion mile (3.5 billion km) journey.
Cassini crossed Saturn's rings without mishap in June 2004 and produced the most revealing photos yet of the rings and massive gas-giant. A problem with the design of an antennae on Cassini almost scrapped Huygens' mission, but engineers altered the spacecrafts' flight plans to resolve the transmission problem.
Now, Huygens is on its own.
Controllers can only that hope years of preparation will pay off. "[Huygens] is on its way, we can't contact it," said Standley. "We can't make any changes of anything that is on board. [It's] just waiting for the right moment."
Huygens to plumb secrets of Saturn moon
By Michael Coren
CNN
(CNN) -- The Huygens probe will plunge through the orange clouds of Saturn's moon Titan Friday, offering scientists their first glimpse of the mysterious moon.
"It's going to be the most exotic place we've ever seen," said Candice Hansen, a scientist for the Cassini-Huygens mission. "We've never landed on the surface of an icy satellite. We know from our pictures that there are very different kinds of geological processes."
If all goes well, the saucer-shaped Huygens will enter the thick atmosphere of Titan Friday at about 5:13 a.m. (ET). The data should start trickling in about five hours later.
The Cassini-Huygens mission is an unprecedented $3.3-billion effort between NASA, the European Space Agency and Italy's space program to study Saturn and its 33 known moons. The two vehicles were launched together from Florida in 1997.
"The mission is to explore the entire Saturnian system in considerably greater detail than we have ever been able to do before: the atmosphere, the internal structure, the satellites, the rings, the magnetosphere," said Cassini program manager Bob Mitchell at NASA.
The Huygens probe, about the size of a Volkswagen-Beetle, has been spinning silently toward Titan since it detached from the Cassini spacecraft on December 24. Cassini will remain in orbit around Saturn until at least July 2008.
"[The Cassini-Huygens mission] will probably help answer some of the big questions that NASA has in general about origins and where we came from and where life came from," said Mitchell.
Titan's atmosphere, a murky mix of nitrogen, methane and argon, resembles Earth's before life began more than 3.8 billion years ago. Scientists think the moon may shed light on how life evolved on Earth.
Finding living organisms, however, is a remote possibility. "It is not out of the question, but it is certainly not the first place I would look," said Hansen. "It's really very cold." A lack of sunlight has put Titan into a deep-freeze. Temperatures hover around -292 F (-180 C) making liquid water scarce and hindering chemical reactions needed for organic life.
New discoveries
The mysteries of Saturn, the sixth planet from the sun, have always enticed researchers. Scientists are perplexed why Saturn, a gas-giant composed primarily of hydrogen and helium, releases more energy than it absorbs from faint sunlight. Titan is also the only moon in the solar system to retain a substantial atmosphere, one even thicker than Earth's.
The 703-pound, battery-powered probe will parachute through Titan's clouds of methane and nitrogen for two and a half hours sampling gases and capturing panoramic pictures. Soon afterward, Huygens will reach the surface. However, its landing site is still a matter of conjecture. Scientists say it could be solid, slushy or even a liquid sea of ethane and hydrocarbons.
"Those are the kinds of things that we have theories about, but we really don't have data," said Hansen.
Huygens is expected to hit the upper atmosphere 789 miles (1,270 km) above the moon at a speed of about 13,700 mph (22,000 km/h). A series of three parachutes will slow the craft to just 15 mph (24 km/h). The chutes and special insulation will protect Huygens from temperature swings and violent air currents. Strong winds -- in excess of 311 mph (500 km/h) --will buffet the craft, at times dragging Huygens sideways after its parachute is deployed.
Sensors will deduce wind speed, atmospheric pressure and the conductivity of Titan's air. Methane clouds and possibly hydrocarbon rain can be analyzed by an onboard gas chromatograph. A microphone will listen for thunder.
Three rotating cameras will snap panoramic views of the moon capturing up to 1,100 images. A radar altimeter will map Titan's topography and a special lamp will illuminate the probe's landing spot to help determine the surface composition.
Engineers say they are confident that Huygens and its suite of six sensitive instruments will survive the descent.
"From an engineering standpoint, I'm very confident in a positive outcome," said Shaun Standley, an ESA systems engineer for Huygens at the Jet Propulsion Laboratory in California. "We've been over this again and again for the last three years fine-tuning this."
As the largest and most sophisticated interplanetary vehicle ever launched, according to NASA, Cassini-Huygens has performed well on its 2.2-billion mile (3.5 billion km) journey.
Cassini crossed Saturn's rings without mishap in June 2004 and produced the most revealing photos yet of the rings and massive gas-giant. A problem with the design of an antennae on Cassini almost scrapped Huygens' mission, but engineers altered the spacecrafts' flight plans to resolve the transmission problem.
Now, Huygens is on its own.
Controllers can only that hope years of preparation will pay off. "[Huygens] is on its way, we can't contact it," said Standley. "We can't make any changes of anything that is on board. [It's] just waiting for the right moment."
