Comet C1999 S4 Linear

SS: S4 Linear discovery before it moved towards Algol the " Queens Eye " ..


S4 Linear near " Queens Eye "

SS: S4 Linear circles around Algol the " Queens Eye " for half a year before making it's run:

S4 Linear near " Queens Eye "

SS: after spending half a year circling Algol the " Queens Eye " S4 Linear begins it's run ..


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THE BASTILLE DAY STORM The coordinated use of NASA and NOAA's tools were crucial to tracking and predicting the development of the most intense storm of the solar cycle, nicknamed the "Bastille Day event." Photo: Chandra image third from left, other three images are the Bastille Day Storm..

Mystery of Cometary X-Rays Solved July 27, 2000 X-rays from Comet C/1999 S4 (LINEAR). On July 14, 2000 the Chandra X-ray Observatory imaged the comet repeatedly for a total of 2 hours and detected X-rays from oxygen and nitrogen ions. The details of the X-ray emission, as recorded on Chandra's Advanced CCD Imaging Spectrometer, show that the X-rays are produced by collisions of ions racing away from the sun (solar wind) with gas in the comet. In the collision the solar ion captures an electron from a cometary atom into a high energy state. The solar ion then kicks out an X-ray as the electron drops to a lower energy state. The Chandra observations showed variations in the amount of X-rays produced by the comet. These were probably due to a solar flare that occurred on July 12 which would have increased the intensity of the solar wind. 

SS: There were three x-class solar flares occurred between July 12th and July 14th which caused the variations in S4 Linear that produced an increase in X-Rays emissions from the comet and likely helped cause it's disintegration on July 28th ...


S4 Linear Punches the Big Bear in the Nose

SS: S4 Linear punch the big bear in the nose and then raced along to cross across his legs tripping him up before he disintegrated:



Hubble Sees Comet Linear Blow its Top July 28, 2000 Lackluster comet LINEAR (C/1999 S4) unexpectedly threw astronomers a curve. Using the Hubble telescope, researchers were surprised to catch the icy comet in a brief, violent outburst when it blew off a piece of its crust, like a cork popping off a champagne bottle. The eruption, the comet's equivalent of a volcanic explosion (though temperatures are far below freezing, at about minus 100 degrees Fahrenheit in the icy regions of the nucleus or core), spewed a great deal of dust into space. This mist of dust reflected sunlight, dramatically increasing the comet's brightness over several hours. Hubble's sharp vision recorded the entire event and even snapped a picture of the chunk of material jettisoned from the nucleus and floating away along the comet's tail.

Above: Science@NASA reader Larry Koehn contributed this illustration of comet LINEAR's motion through the Solar System. The comet passed 56 million km from Earth on July 22nd and 114 million km from the Sun on July 26, 2000. It appears to be a first-time visitor to the inner solar system traveling in an orbit that will eventually return it beyond Neptune in 2013.

Above: This 3-frame sequence of Hubble Space Telescope images spanning July 5th through 7th shows the brightness of comet LINEAR increasing by 50% and then subsiding again as it blows off a piece of its crust, like a cork popping off a champagne bottle. [more information]

Comet LINEAR Misbehaves Comet LINEAR did not become a spectacular naked-eye object as many stargazers had hoped, but it is intriguing astronomers with its peculiar dynamic behavior. July 28, 2000 -- Dashing the hopes of many sky watchers around the world, comet C/1999 S4 (LINEAR) was too faint to see with the unaided eye as it made its closest approach to Earth on July 22nd. Its visual magnitude appears to have peaked between magnitude +6.0 and +6.5, just below the threshold for naked-eye observations. Nevertheless, the comet is still a good target for binoculars or small telescopes. LINEAR may have disappointed casual stargazers, but it is intriguing professional astronomers with unpredictable behavior including jets that are perturbing the comet's orbit and an outburst in July that may have sent a fragment hurtling away from the comet's core. Comet LINEAR surprised astronomers using the Hubble Space Telescope (HST) with a brief, violent outburst on July 5, 2000. The comet's brightness soared by a factor of 1.5 during a four hour period. Two days later astronomers spotted at least one house-sized fragment trailing the nucleus by more than 450 km.

S4 Linear Continues to Disintegrate during Beehive Eclipse

Meltdown! Comet LINEAR continues to disintegrate and could disappear completely within a few days. July 31, 2000 -- Astronomers around the world continue to monitor the unexpected disintegration of comet C/1999 S4 (LINEAR). Intense solar heating apparently triggered a massive disruption of the comet's fragile icy core when it passed close to the Sun last week. It is still bright enough to see through small telescopes so even amateur astronomers can watch the comet as it dissolves. If you do plan to look, don't wait. Experts think that comet LINEAR might disappear completely in a few days.

The break up of a bright comet is unusual but not unprecedented. For example, comet Shoemaker-Levy 9 (SL-9) broke up before it struck Jupiter in 1994. SL-9 was discovered after it fragmented, so there is no record of what happened as it came to pieces. With comet LINEAR, astronomers have a ringside seat for the entire show.

"At perihelion there are very rapid aspect changes as regions of the nucleus previously in shadow are suddenly subjected to intense heating," continued Kidger. "This causes strong thermal stresses" that may have been a primary cause of LINEAR's breakup. Something was already amiss the day before Comet LINEAR reached perihelion at a distance of 114 million km (0.74 AU) from the Sun. "The very first images on July 25th were enough to show me that something odd was going on," recounts Kidger. "The comet's inner coma was no longer teardrop-shaped (the solar wind flowing around the comet's head causes this shape). It had a shape like a short, fat cigar. My first thought was 'Shoemaker-Levy.' It looked just like those first images of Comet Shoemaker-Levy 9 after it was discovered."

Comet Formed Puzzlingly Close to Earth, Study Suggests Astronomers were delighted in July 2000 to see a cryptically named comet C/1999S4 (LINEAR) break apart as it hurtled within 35,000,000 miles (56,000,000 km) of Earth. The icy undoing, caused by the Sun's energy melting the comet, provided a unique and ongoing glimpse into our solar system's early beginnings. The latest study of comet LINEAR has revealed it may have formed closer to Earth than other comets. The finding may eventually help build a more accurate picture of how our solar system developed, said comet scientist Hal Weaver from Johns Hopkins University. Led by astronomer Hideyo Kawakita of the Gunma Astronomical Observatory in Japan, a 19-person team of scientists observed LINEAR at several telescopes in Japan as well as at the Subaru Telescope in Hawaii. Their findings were reported in the Nov. 2 issue of the journal Science. Astronomers think of comets as time capsules from the formation of the solar system. Comets are too small to have been affected by the chemical and physical processes that forced planets to evolve, said Weaver. Observations of comets therefore, although limited by their distance, tell scientists a lot about the evolution of our world, our solar system, and the universe. In the past, comets have been characterized by the micro-movements of water molecules or hydrogen atoms. But the researchers in Japan used a new atomic measuring stick with LINEAR: how the atoms spin in molecules made with two hydrogen atoms and one nitrogen atom. The spins of these atoms provide clues about where they originated relative to the Sun. These atoms were floating in the hot nuclear soup of the Sun's birth, and their movements were determined by how much radiation they received from the proto-Sun. By laws of subatomic physics, the spin of atoms once set never changes. The scientists discovered that the atoms of LINEAR place its origin in a surprising location: between Saturn and Uranus. Most comets, said Weaver, are thought to have originated further out from the Sun, past Neptune.


S4 Linear near the Moon

SS: As S4 Linear cross the ecliptic it aligned closely with the moon ..


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