http://www.freerepublic.com/tag/comet/ en-us Sun, 16 Jun 2013 07:50:32 GMT Focus Forum 15 http://www.freerepublic.com/focus/f-chat/3031872/posts Man owes a lot to chunks of rock and ice floating through space. From ancient jewellery to water and possibly even the beginnings of life itself, scientists are discovering that comets have contributed in many ways to the development of life on the planet, Robert Matthews writes Since their discovery in an Egyptian cemetery more than a century ago, a handful of metal beads have perplexed archaeologists. As jewellery, the beads seem decidedly downmarket, being made of nothing more glamorous than iron. Yet clearly their owner, dead for more than 5,000 years, held them in great esteem - as do... The National http://www.freerepublic.com/focus/f-chat/3031872/posts#comment Sun, 16 Jun 2013 07:50:32 GMT http://www.freerepublic.com/focus/f-news/2788555/posts Comet Hartley 2 contains water more like that found on Earth than prior comets seem to have, researchers say. A study using the Herschel space telescope aimed to measure the quantity of deuterium, a rare type of hydrogen, present in the comet's water. The comet had just half the amount of deuterium seen in comets. The result, published in Nature, hints at the idea that much of the Earth's water could have initially came from cometary impacts. Just a few million years after its formation, the early Earth was rocky and dry; something must have brought the water that covers... BBC http://www.freerepublic.com/focus/f-news/2788555/posts#comment Thu, 6 Oct 2011 01:41:44 GMT http://www.freerepublic.com/focus/f-bloggers/1250694/posts Given the reality of the dark spots, which soon became known as "atmospheric holes" because of their appearance in the images, there is only one explanation which has endured over all these years to present. That is, the holes are due to the shadowing of the atmospheric light by an object above the atmosphere. This object simply cannot be a stony or iron meteor because the holes are very large, tens of miles in diameter. A rock of this size would provide a disastrous impact on the Earth's surface. As it turns out, water vapor is very good at absorbing... University of Iowa http://www.freerepublic.com/focus/f-bloggers/1250694/posts#comment Wed, 20 Oct 2004 06:13:25 GMT http://www.freerepublic.com/focus/f-chat/2266269/posts While investigating the chemical make-up of comets, Prof. Akiva Bar-Nun of the Department of Geophysics and Planetary Sciences at Tel Aviv University found they were the source of missing ingredients needed for life in Earth's ancient primordial soup. "When comets slammed into the Earth through the atmosphere about four billion years ago, they delivered a payload of organic materials to the young Earth, adding materials that combined with Earth's own large reservoir of organics and led to the emergence of life," says Prof. Bar-Nun. ScienceDaily http://www.freerepublic.com/focus/f-chat/2266269/posts#comment Sat, 6 Jun 2009 17:52:58 GMT http://www.freerepublic.com/focus/f-chat/2407089/posts An investigation by the University of Kansas' Adrian Melott and colleagues reveals a promising new method of detecting past comet strikes upon Earth and gauging their frequencyLAWRENCE, Kan. — It's the stuff of a Hollywood disaster epic: A comet plunges from outer space into the Earth's atmosphere, splitting the sky with a devastating shock wave that flattens forests and shakes the countryside. But this isn't a disaster movie plotline. "Comet impacts might be much more frequent than we expect," said Adrian Melott, professor of physics and astronomy at the University of Kansas. "There's a lot of interest in the rate... University of Kansas http://www.freerepublic.com/focus/f-chat/2407089/posts#comment Mon, 14 Dec 2009 13:27:46 GMT http://www.freerepublic.com/focus/f-news/3025659/posts As Comet C/2012 S1 (ISON) heads closer to Earth, we’re getting a better view of what has been billed by some as the “Comet of the Century.” Astronomers say these new photos from the Gemini North telescope on Mauna Kea, Hawai‘i provide hints of how well this comet might survive one of the closest comet encounters with the Sun ever recorded, on November 28, 2013. With astronomy enthusiasts hopeful and optimistic about having a spectacular comet visible in our skies, it’s anyone’s guess if the comet will actually survive its extremely close pass of the Sun to become early... Universe Today http://www.freerepublic.com/focus/f-news/3025659/posts#comment Fri, 31 May 2013 02:08:03 GMT http://www.freerepublic.com/focus/f-chat/3020964/posts Explanation: Once the famous sunset comet, PanSTARRS (C/2011 L4) is now visible all night from much of the northern hemisphere, bound for the outer solar system as it climbs high above the ecliptic plane. Dimmer and fading, the comet's broad dust tail is still growing, though. This widefield telescopic image was taken against the starry background of the constellation Cepheus on May 15. It shows the comet has developed an extensive anti-tail, dust trailing along the comet's orbit (to the left of the coma), stretching more than 3 degrees across the frame. Since the comet is just over 1.6 astronomical... NASA http://www.freerepublic.com/focus/f-chat/3020964/posts#comment Sat, 18 May 2013 13:07:35 GMT http://www.freerepublic.com/focus/f-chat/3013904/posts What are some of the conspiracy theories out there about Comet ISON? One currently circulating claim states that Comet ISON has “companions” that have been imaged trailing it. While comets do indeed fragment on occasion, the culprits that can be seen in the .gif animation circulating the internet are easily identified by photography experts as hot pixels in the camera. Another even more extravagant claim is that Comet ISON will somehow appear “as bright as the Sun.” Even if Comet ISON reaches an expected magnitude equal to that of the full Moon at -13, it will do so when it... www.universetoday.com http://www.freerepublic.com/focus/f-chat/3013904/posts#comment Tue, 30 Apr 2013 01:01:11 GMT http://www.freerepublic.com/focus/f-chat/3011592/posts Here’s our first good look at Comet (C/2012 S1) ISON. The Hubble Space Telescope captured this shot on April 10, when the comet was slightly closer than Jupiter’s orbit at a distance of 634 million kilometers (394 million miles) from Earth. Later this year, this comet could become a brilliant object in the sky, perhaps 10 times brighter than Venus. Astronomers say preliminary measurements from the Hubble images suggest that the nucleus of ISON is no larger than 4-6 km (3-4 miles) across. The astronomers said this is remarkably small considering the high level of activity observed in the comet... universetoday.com http://www.freerepublic.com/focus/f-chat/3011592/posts#comment Wed, 24 Apr 2013 01:37:51 GMT http://www.freerepublic.com/focus/f-chat/2996866/posts The Comet Pan-STARRS may be a challenge to spot in the evening sky, but it still dazzled stargazers around the world when it paired up with the moon Tuesday (March 12). Comet Pan-STARRS is currently appearing low on the western horizon just after sunset, making it hard to pick out in the bright evening twilight for some observers. But on Tuesday evening, a slender crescent moon served as a celestial guide for those stargazers with clear, dark skies. Just northwest of Rio Rancho, N.M., astrophotographer Josh Knutson and his 8-year-old daughter Aurora were amazed at the sight of Comet Pan-STARRS... space.com http://www.freerepublic.com/focus/f-chat/2996866/posts#comment Thu, 14 Mar 2013 18:58:11 GMT http://www.freerepublic.com/focus/f-chat/2996107/posts A fireball that appeared over the Sri Lankan province of Polonnaruwa on December 29, 2012 was a meteorite containing algae fossils, according to a paper published in the Journal of Cosmology. A team of researchers, led by Jamie Wallis of Cardiff University, believes that these fossils provide evidence of cometary panspermia, the hypothesis that life originated in outer space and comets brought it to Earth. Scientists at the Sri Lankan Medical Research Institute in Colombo forwarded 628 stone fragments that allegedly fell from the fireball to Cardiff University, where Wallis' team indentified three as originating from a carbonaceous chondrite. The... Phys.Org http://www.freerepublic.com/focus/f-chat/2996107/posts#comment Tue, 12 Mar 2013 17:27:50 GMT http://www.freerepublic.com/focus/f-chat/2995501/posts comet crashing into the Earth some 13,000 years ago was thought to have spelled doom to a group of early North American people, and possibly the extinction of ice age beasts in the region. But the space rock was wrongly accused, according to a group of 16 scientists in fields ranging from archaeology to crystallography to physics, who have offered counterevidence to the existence of such a collision. Almost 13,000 years ago, a prehistoric Paleo-Indian group known as the Clovis culture suffered its demise at the same time the region underwent significant climate cooling known as the Younger Dryas. Animals... nbc http://www.freerepublic.com/focus/f-chat/2995501/posts#comment Sun, 10 Mar 2013 22:10:46 GMT http://www.freerepublic.com/focus/f-chat/2995016/posts The icy mass, called C/2011 L4 Pan-Starrs, should be visible with binoculars or a telescope from 8 March. But in the following days, it will become even brighter and could be seen with the naked eye. Astronomers in the Southern Hemisphere have already been treated to a fly past, with reports that the body was as bright as stars in the Plough. The comet was first discovered in June 2011, spotted by the Pan-Starrs telescope (hence its name) in Hawaii as a faint object more than a billion kilometres away. Astronomers believe it originated in the Oort Cloud, a region... bbc http://www.freerepublic.com/focus/f-chat/2995016/posts#comment Sat, 9 Mar 2013 00:34:55 GMT http://www.freerepublic.com/focus/f-chat/2993836/posts Explanation: Two impressive comets will both reach their peak brightness during the next two weeks. Taking advantage of a rare imaging opportunity, both of these comets were captured in the sky together last week over the Atacama desert in South America. Comet C/2012 F6 (Lemmon), visible on the upper left of the above image, is sporting a long tail dominated by glowing green ions. Comet C/2011 L4 (PanSTARRS), visible near the horizon on the lower right, is showing a bright tail dominated by dust reflecting sunlight. The tails of both comets point approximately toward the recently set Sun. Comet Lemmon... NASA http://www.freerepublic.com/focus/f-chat/2993836/posts#comment Wed, 6 Mar 2013 00:41:44 GMT http://www.freerepublic.com/focus/f-chat/2993690/posts A Super Fast Comet Is Headed For Mars The EconomistMarch 5, 2013Shutterstock A PAIR of middle-aged tourists (see previous post) are not the only thing headed for Mars. Comet C/2013 A1 (Siding Spring) is also on its way. Discovered on January 3rd, some calculations of its orbit, according to Phil Plait, the rather good “Bad Astronomer”, have it passing 37,000km above the surface of the planet in October 2014—roughly the height at which communication satellites orbit Earth, and a remarkably close shave by cosmic standards. An official NASA website puts the most likely “close-approach” distance between the comet and Mars... TBI http://www.freerepublic.com/focus/f-chat/2993690/posts#comment Tue, 5 Mar 2013 18:10:50 GMT http://www.freerepublic.com/focus/f-news/2993528/posts This year seems to be one for comets. In addition to the two projectiles that will zoom near Earth, a third one has recently been discovered. The newest one, though, won't fly by our planet. Instead, it will pass uncomfortably close to Mars in 2014. Named C/2013 A1, the comet will fly near the Red Planet on Oct. 19, 2014 according to preliminary orbital prediction models. The icy missile is thought to have first originated from the Oort Cloud, which is a hypothetical region containing billions of cometary nuclei located around our solar system. Comets have struck planets in the... Science World Report http://www.freerepublic.com/focus/f-news/2993528/posts#comment Tue, 5 Mar 2013 05:03:58 GMT http://www.freerepublic.com/focus/f-chat/2993109/posts In case you just can’t get enough impact news, it looks like Mars may actually get hit by a comet in 2014! As it stands right now, the chance of a direct impact are small, but it’s likely Mars will get pelted by the debris associated with the comet. The comet is called C/2013 A1, discovered on Jan. 3, 2013 by the Australian veteran comet hunter Robert McNaught. Extrapolating its orbit, they found it will make a very near pass of Mars around Oct. 19, 2014, missing the planet by the nominal distance of about 100,000 kilometers. Observations taken at... The Slate http://www.freerepublic.com/focus/f-chat/2993109/posts#comment Sun, 3 Mar 2013 22:33:55 GMT http://www.freerepublic.com/focus/f-chat/2991393/posts A recently discovered comet will make an uncomfortably-close planetary flyby next year — but this time it’s not Earth that’s in the cosmic crosshairs. According to preliminary orbital prediction models, comet C/2013 A1 will buzz Mars on Oct. 19, 2014. According to calculations by NASA’s Jet Propulsion Laboratory (JPL), close approach data suggests the comet is most likely to make a close pass of 0.0007 AU (that’s approximately 63,000 miles from the Martian surface). However, there’s one huge caveat. Due to uncertainties in the observations — the comet has only been observed for 74 days (so far), so it’s difficult... discovery.com http://www.freerepublic.com/focus/f-chat/2991393/posts#comment Tue, 26 Feb 2013 17:02:24 GMT http://www.freerepublic.com/focus/f-chat/2989304/posts Explanation: For now, Comet Lemmon (C/2012 F6a), and Comet PanSTARRS (C/2011 L4) are sweeping through southern skies. Lemmon's lime green coma and thin tail are near the left edge of this telephoto scene, a single frame from a timelapse video (vimeo here) recorded on February 12, tracking its motion against the background stars. Comet Lemmon's path brought it close to the line-of-sight to prominent southern sky treasures the Small Magellanic Cloud and globular cluster 47 Tucanae (right). Sporting a broader, whitish tail, Comet PanSTARRS appears in later video frames moving through the faint constellation Microscopium. Visible in binoculars and small... NASA http://www.freerepublic.com/focus/f-chat/2989304/posts#comment Sun, 17 Feb 2013 04:08:30 GMT http://www.freerepublic.com/focus/f-chat/2976659/posts Later this year, Comet ISON could put on an unforgettable display as it plunges toward the sun for a fiery encounter likely to turn the "dirty snowball" into a naked-eye object in broad daylight. At the moment, however, it doesn't look like much. John Chumack sends this picture, taken Jan. 8th, from his private observatory in Yellow Springs, Ohio: SpaceWeather.com http://www.freerepublic.com/focus/f-chat/2976659/posts#comment Thu, 10 Jan 2013 07:09:17 GMT http://www.freerepublic.com/focus/f-chat/2973601/posts A comet blazing toward Earth could outshine the full moon when it passes by at the end of next year—if it survives its close encounter with the sun. The recently discovered object, known as comet ISON, is due to fly within 1.2 million miles (1.9 million km) from the center of the sun on Nov. 28, 2013 said astronomer Donald Yeomans, head of NASA’s Near Earth Object Program at the Jet Propulsion Laboratory in Pasadena, Calif. As the comet approaches, heat from the sun will vaporize ices in its body, creating what could be a spectacular tail that is visible... Reuters http://www.freerepublic.com/focus/f-chat/2973601/posts#comment Mon, 31 Dec 2012 11:58:25 GMT http://www.freerepublic.com/focus/f-chat/2972591/posts A newly discovered comet has the potential to put on a dazzling celestial display late next year, when it will be so bright you may be able to see it briefly in the daytime sky. The discovery of the object named Comet ISON was announced Monday (Sept. 24) by Russians Vitali Nevski and Artyom Novichonok, who detected it in photographs taken three days earlier using a 15.7-inch (0.4-meter) reflecting telescope of the International Scientific Optical Network (ISON), near Kislovodsk. The new comet is officially known as C/2012 S1. When first sighted, Comet ISON was 625 million miles (1 billion kilometers)... space.com http://www.freerepublic.com/focus/f-chat/2972591/posts#comment Thu, 27 Dec 2012 14:32:20 GMT http://www.freerepublic.com/focus/f-news/2937666/posts Sky-watchers in Australia ogle comet Lovejoy late last year. If astronomers' early predictions hold true, the holidays next year may hold a glowing gift for stargazers—a superbright comet, just discovered streaking near Saturn.Even with powerful telescopes, comet 2012 S1 (ISON) is now just a faint glow in the constellation Cancer. But the ball of ice and rocks might become visible to the naked eye for a few months in late 2013 and early 2014—perhaps outshining the moon, astronomers say.The comet is already remarkably bright, given how far it is from the sun, astronomer Raminder Singh Samra said. What's more, 2012... National Geographic http://www.freerepublic.com/focus/f-news/2937666/posts#comment Fri, 28 Sep 2012 20:20:52 GMT http://www.freerepublic.com/focus/f-chat/2936767/posts Vitali Nevski and Artyom Novichonok, of the International Scientific Optical Network (ISON) in Russia, discovered comet C/2012 S1 (ISON) on 21 September via images taken with a 40-centimetre reflecting telescope. Other sky-watchers soon spotted it, and the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts, announced the find yesterday. From the combined observations, astronomers were able to trace the comet's recent path and find images of it dating back to late December 2011. From there they calculated a near-parabolic orbit that has comet ISON headed almost straight towards the sun. Astronomers at the Remanzacco Observatory in Italy think that... New Scientist http://www.freerepublic.com/focus/f-chat/2936767/posts#comment Thu, 27 Sep 2012 01:29:10 GMT http://www.freerepublic.com/focus/f-chat/2930086/posts On Monday, Jupiter took a massive hit from a meteor, which was spotted by amateur astronomers based in the US—and if previous evidence is anything to go by, it could have saved Earth from a massive collision in the process. Dan Peterson of Racine, Wisconsin, was gazing at Jupiter on Monday when he saw a bright, white flash on the surface of the planet. When he posted his observation online, another astrophotographer, George Hall, discovered he'd unknowingly captured the massive explosion on video. Turns out it was probably a meteor striking the surface of the planet—and you can watch the... Gizmodo http://www.freerepublic.com/focus/f-chat/2930086/posts#comment Wed, 12 Sep 2012 21:41:21 GMT