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Comet Hale Bopp

Comet Hale-Bopp (formally designated C/1995 O1) was arguably the most widely observed comet of the twentieth century, and one of the brightest seen for many decades. It was visible to the naked eye for a record 18 months, twice as long as the previous record holder, the Great Comet of 1811.

Hale-Bopp was discovered on July 23, 1995, at a great distance from the Sun, raising expectations that the comet would brighten considerably by the time it passed close to Earth. Although predicting the brightness of comets with any degree of accuracy is very difficult, Hale-Bopp met or exceeded most predictions when it passed perihelion on April 1, 1997. The comet was dubbed the Great Comet of 1997.

The passage of Hale-Bopp was notable also for inciting a comet-related panic. Rumours that an alien spacecraft was following the comet gained remarkable currency, and inspired a mass suicide among followers of the Heaven's Gate cult.

1. Discovery of the comet

The comet was discovered in 1995 by two independent observers, Alan Hale and Thomas Bopp, both in the United States.

Hale had spent many hundreds of hours searching for comets without success, and was tracking known comets from his driveway in New Mexico when he chanced upon Hale-Bopp just after midnight. The comet had an apparent magnitude of 10.5 and lay near the globular cluster M70 in the constellation of Sagittarius. Hale first established that there was no other deep-sky object near M70, and then consulted a directory of known comets, finding that none were known to be in this area of the sky. Once he had established that the object was moving relative to the background stars, he emailed the Central Bureau for Astronomical Telegrams, the clearing house for astronomical discoveries.

Bopp did not own a telescope. He was out with friends near Stanfield, Arizona observing star clusters and galaxies when he chanced across the comet while at the eyepiece of his friend's telescope. He realized he might have spotted something new when, like Hale, he checked his star maps to determine if any other deep-sky objects were known to be near M70, and found that there were none. He alerted the Central Bureau for Astronomical Telegrams through a Western Union telegram. Brian Marsden, who has run the bureau since 1968, laughed, "Nobody sends telegrams anymore. I mean, by the time that telegram got here, Alan Hale had already e-mailed us three times with updated coordinates."

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The following morning, it was confirmed that this was a new comet, and it was named Comet Hale-Bopp, with the designation C/1995 O1. The discovery was announced in International Astronomical Union circular 6187.

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The comet may have been observed by ancient Egyptians during the reign of pharaoh Pepi I (2332 – 2283 BCE). In Pepi's pyramid in Saqqara is a text referring to an "nhh-star" as a companion of the pharaoh in the heavens, where "nhh" is the hieroglyph for long hair. edit

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Partially hydrolyzed guar gum (PHGG) is produced by the partial enzymatic hydrolysis of guaran, the galactomannan of the endosperm of guar seeds (guar gum). It is a neutral polysaccharide consisting of a mannose backbone chain with single galactose side units occurring on almost two out of every three mannose units. The average molecular weight is about 25,000 Daltons. This gives a PHGG that still assays and functions as a soluble dietary fiber. PHGG as sold commercially is completely soluble, acid and heat stable, unaffected by ions, and will not gel at high concentrations. PHGG is fully fermentable in the large bowel with a high rate of volatile fatty acid formation. The pH of the feces is lowered along with an increase in fecal bulk that mainly consists of bacteria cell mass and water. Clinical studies have demonstrated a prebiotic affect of PHGG. Studies have also shown that PHGG can be used to maintain regularity. PHGG is used in foods for particulate suspension, emulsification, anti-staling, ice crystal control, and reduced fat baked goods.

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621130720269120532 Discovery of the comet 0 no
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115075060127286424 and another 2 no
177064124220119817 And another weight test. 3 no
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158388249095347891 Nutrition 5 yes
194582249316404417 Testing weights 5 no
358350328109960390 another test section 6 no
204077086516818870 Test Short Section 7 no
189670391116566689 test section 8 no
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