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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...

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...

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...

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)...

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...

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...

Central Mexico’s Lake Cuitzeo contains melted rock formations and nanodiamonds that suggest a comet impacted Earth around 12,900 years ago, scientists say. CREDIT: Israde et al. (2012) New evidence supports the idea that a huge space rock collided with our planet about 13,000 years ago and broke up in Earth's atmosphere, a new study suggests. This impact would have been powerful enough to melt the ground, and could have killed off many large mammals and humans. It may even have set off a period of unusual cold called the Younger Dryas that began at that time, researchers say. The...

At least 5 percent of the comets orbiting our sun may have been stolen from other stars, scientists say. Our solar system is thought to include trillions of comets -- small chunks of rock and ice -- that circle the sun in a spherical swarm called the Oort cloud, a region that extendsabout 100,000 times the distance from the Earth to the sun in any direction. The average distance between the Earth and sun is 93 million miles (150 million kilometers). Now scientists suggest that many of these bodies may actually have originated around other stars and were snatched up...

From Physorg.com Comet Lovejoy was only discovered a couple of weeks ago. It was supposed to melt as it came so close to the sun that the temperatures would hit several million degrees.But astronomers watching live with NASA telescopes were shocked when a bright spot emerged on the sun’s other side. Lovejoy lived.

Explanation: Historically active, this year's Leonid meteor shower was diminished by bright moonlight. Still, faithful night sky watchers did see the shower peak on November 18 and even the glare of moonlight didn't come close to masking this brilliant fireball meteor. The colorful meteor trail and final flare was captured early that morning in western skies over the Canary Island Observatorio del Teide on Tenerife. Particles of dust swept up when planet Earth passes near the orbit of periodic comet Tempel-Tuttle, Leonid meteors typically enter the atmosphere at nearly 70 kilometers per second. Looking away from the Moon, the wide...

Explanation: Did a sun-diving comet just cause a solar explosion? Probably not. This past weekend a comet dove toward the Sun and was followed very quickly by a Coronal Mass Ejection (CMEs) from the other side of the Sun. The first two sequences in the above video shows the spectacular unfolding of events as seen by the Sun-orbiting SOHO satellite, while the same events were also captured by both Sun-orbiting STEREO satellites. Now sungrazer comets that break up as they pass near the Sun are not all that rare -- hundreds have been cataloged over the past few years. CMEs...

It seemed like such an elegant answer to an age-old mystery: the disappearance of what are arguably North America’s first people. A speeding comet nearly 13,000 years ago was the culprit, the theory goes, spraying ice and rocks across the continent, killing the Clovis people and the mammoths they fed on, and plunging the region into a deep chill. The idea so captivated the public that three movies describing the catastrophe were produced. But now, four years after the purportedly supportive evidence was reported, a host of scientific authorities systematically have made the case that the comet theory is “bogus.”...

Recent observations of sunspots, the high temperature of the corona and CMEs strongly suggest that they are all caused by highly energetic solid bodies falling into the Sun. This hypothesis is consistent with the rapid (3000 mph) downward flow of gases in sunspot interiors observed by SOHO, their lower temperatures, and the presence of large quantities of water in their spectra. The high velocity of the incoming body entrains the surface gases, carrying them rapidly downward. The vaporization of the bodies cools the local gases and the water released from the bodies produces the observed spectra. Solar flares and CMEs...

Astronomer Brian G. Marsden, a comet and asteroid tracker who stood sentinel to protect the Earth from collisions with interplanetary rocks and other remnants of the solar system's creation, died Thursday of cancer at Lahey Clinic Medical Center in Burlington, Mass. He was 73. Director emeritus of the Minor Planet Center at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., Marsden was perhaps best known for his 1998 announcement that an asteroid known as 1997 XF11 might strike the Earth in 2028, causing untold damage. The announcement sparked additional studies which quickly showed that such an impact was unlikely. Marsden,...

A FEW weeks ago, an asteroid almost 30 feet across and zipping along at 38,000 miles per hour flew 28,000 miles above Singapore. Why, you might reasonably ask, should non-astronomy buffs care about a near miss from such a tiny rock? Well, I can give you one very good reason: asteroids don’t always miss. If even a relatively little object was to strike a city, millions of people could be wiped out. Thanks to telescopes that can see ever smaller objects at ever greater distances, we can now predict dangerous asteroid impacts decades ahead of time. We can even use...

Showers are expected Thursday, but not the wet kind that have plagued Seattle all summer. The Perseid meteor shower will be visible Thursday night, and viewing conditions should be optimal. The meteor shower appears every year as the Earth enters a band of dust that trails the comet Swift-Tuttle. It's one of of the more reliable night-sky events for stargazers in Seattle, and this year's show could be easier to watch because of clear skies and limited moonlight.

One wonders... Did the inhabitants of galaxy NGC 891 duck when Comet McNaught flew past the edge-on spiral on the morning of June 8th? Mike O'Connor and Tristan Dilapo took this picture of the cosmic close encounter from Colden, New York: (click on photo to enlarge) "The comet was only 10 degrees above the horizon," says O'Connor. "Nevertheless, we got a good picture using a 12-inch telescope and an SBIG ST9-E camera."And, no, the denizens of that distant galaxy did not flinch, flee, duck or take notice in any way. NGC 891 is 30 million light years away, far removed...

Comet strikes are an unlikely cause of past mass extinctions on Earth, according to computer simulations. Scientists used the simulations to model the paths of long-period comets, to determine the likelihood of these "dirty snowballs" striking our planet. The University of Washington, Seattle, research appears in Science journal. How many mass extinctions in Earth's history were caused by these icy bodies crashing into our planet has been a subject of considerable debate. Many scientists agree that an asteroid strike 65 million years ago wiped out the dinosaurs. But there is uncertainty about how many other such events were triggered by...

Jupiter took a bullet for us last weekend. An object, probably a comet that nobody saw coming, plowed into the giant planet’s colorful cloud tops sometime Sunday, splashing up debris and leaving a black eye the size of the Pacific Ocean. This was the second time in 15 years that this had happened. The whole world was watching when Comet Shoemaker-Levy 9 fell apart and its pieces crashed into Jupiter in 1994, leaving Earth-size marks that persisted up to a year. That’s Jupiter doing its cosmic job, astronomers like to say. Better it than us. Part of what makes the...

Scientists have found evidence that another object has bombarded Jupiter, exactly 15 years after the first impacts by the comet Shoemaker-Levy 9. Following up on a tip by an amateur astronomer, Anthony Wesley of Australia, that a new dark "scar" had suddenly appeared on Jupiter, this morning between 3 and 9 a.m. PDT (6 a.m. and noon EDT) scientists at NASA's Jet Propulsion Laboratory in Pasadena, Calif., using NASA's Infrared Telescope Facility at the summit of Mauna Kea, Hawaii, gathered evidence indicating an impact.

On the morning of June 30, 1908, the sky exploded over a remote region of central Siberia. A fireball powerful as hundreds of Hiroshima atomic blasts scorched through the upper atmosphere "as if there was a second sun," according to one eyewitness. Scientists today think a small fragment of a comet or asteroid caused the "Tunguska event," so named for the Tunguska river nearby. No one knows for certain, however, because no fragment of the meteoroid has ever been found. The explosion was so vast—flattening and incinerating over an 800 square-mile swath of trees—that generations of amateur sleuths have put...

Are comets born in great swarms? The puzzling abundance of comets in short solar orbits has led a pair of astronomers to suggest that they are fragments of larger bodies that crumbled as they entered the inner solar system. Short-period comets take less than 200 years to circle the sun and are thought to originate in the Kuiper belt of icy objects beyond Neptune. Some Kuiper-belt objects (KBOs) are in vulnerable orbits that allow the gravity of the outer planets to tug them inwards, where the sun's heat turns them into comets. However, there seem to be too few KBOs...

Did Comets Cause Ancient American Extinctions?Anne Casselman for National Geographic NewsMay 6, 2008 Debate has heated up over a controversial theory that suggests huge comet impacts wiped out North America's large mammals nearly 13,000 years ago. The hypothesis, first presented in May 2007, proposes that an onslaught of extraterrestrial bodies caused the mass extinction known as the Younger Dryas event and triggered a period of climatic cooling. The theory has been debated widely since it was introduced, but it drew new scrutiny in March at the annual meeting of the Society for American Archaeology annual meeting in Vancouver, Canada. Stuart...

WASHINGTON (Reuters) - Samples of rock dust retrieved from a comet called Wild 2 are forcing scientists to alter they way they think about these intriguing objects that streak through our solar system. A chemical analysis of the samples brought back to Earth by NASA's Stardust spacecraft showed that the comet is much more like an asteroid than scientists had expected. Comets are celestial bodies made of rock, dust and ice with characteristic tails of gas and dust streams that are formed in the solar system's distant, frigid reaches. A long-standing notion had been they were sort of a frozen...

For FReepers in the western US (& Hawaii), I have a heads-up for - potentially - a really nice meteor display early this coming Saturday morning. Points east will not be able to see the peak of the display because - at 4:36 AM PDT - twilight or daytime will already have occurred. The best show will be looking to the northeast. There will be a 3/4 full waning moon high in the sky, so if the observer can shield oneself from the moon behind an obstacle (phone pole, house, car, tree, etc.) the viewing will be improved. I was...

June 28, 2007 Comet theory collides with Clovis research, may explain disappearance of ancient people A theory put forth by a group of 25 geo-scientists suggests that a massive comet exploded over Canada, possibly wiping out both beast and man around 12,900 years ago, and pushing the earth into another ice age. University of South Carolina archaeologist Dr. Albert Goodyear said the theory may not be such "out-of-this-world" thinking based on his study of ancient stone-tool artifacts he and his team have excavated from the Topper dig site in Allendale, as well as ones found in Georgia, North Carolina and...

The so-called ‘Tunguska Event’ refers to a major explosion that occurred on 30 June 1908 in the Tunguska region of Siberia, causing the destruction of over 2000 km2 of taiga, globally detected pressure and seismic waves, and bright luminescence in the night skies of Europe and Central Asia, combined with other unusual phenomena. The ‘Tunguska Event’ may be related to the impact with the Earth of a cosmic body that exploded about 5–10 km above ground, releasing in the atmosphere 10–15 Mton of energy. Fragments of the impacting body have never been found, and its nature (comet or asteroid) is...

mammoth some 12,900 years ago. A team of two dozen scientists say the culprit was likely a comet that exploded in the atmosphere above North America. The explosions sent a heat and shock wave across the continent, pelted the ground with a layer of telltale debris, ignited massive wildfires and triggered a major cooling of the climate, said nuclear analytic chemist Richard Firestone of Lawrence Berkeley Laboratory, one of the scientists who presented the controversial new theory Thursday at a conference of the American Geophysical Union in Acapulco. At least 15 species, mostly large mammals including mammoths, mastadons, giant ground...

Comets and disaster in the Bronze AgeCosmic impact is gaining ground as an explanation of the collapse of civilisations, writes Benny Peiser At some time around 2300BC, give or take a century or two, a large number of the major civilisations of the world collapsed. The Akkadian Empire in Mesopotamia, the Old Kingdom in Egypt, the Early Bronze Age societies in Israel, Anatolia and Greece, as well as the Indus Valley civilisation in India, the Hilmand civilisation in Afghanistan and the Hongshan Culture in China - the first urban civilisations in the world - all fell into ruin at more...

The giant comet, known as 2000 CR105, measures some 400 kilometers across... Brett Gladman of the Observatoire de la Côte d'Azur in Nice, France, and his colleagues have discovered... that 2000 CR105 orbits the sun in 3175 years and never comes closer than 6.6 billion kilometers--well beyond Neptune's orbit. The farthest point of the highly eccentric orbit lies 58.2 billion kilometers from the sun--13 times as far as Neptune... One possibility is that 2000 CR105's orbit evolved into its freakish shape gradually, due to small, periodic gravitational nudges from Neptune. Computer simulations imply that such a "diffusive chaos" scenario is...

IRC+10216, also known as CW Leonis, was once a well-behaved main-sequence star as our own Sun is now... When astronomers turned the satellite toward IRC+10216 they discovered a substantial cloud of water vapor about 100 AU across. ("AU" --short for Astronomical Unit-- is a unit of length used by astronomers. One AU equals the mean distance between Earth and the Sun.) "There must be about four Earth-masses of frozen water around IRC+10216 to produce the vapor cloud we see," says Melnick. The water vapor probably does not come from the vaporization of oceans on an Earth-like planet, because there wouldn't...

The Stardust mission to bring back samples of comet and interstellar dust was more successful than they had hoped, scientists said yesterday. The 100-pound sample container from the seven-year mission, which landed on the salt flats of Utah on Sunday, captured thousands of particles, perhaps even a million, that originated at the edge of the solar system or from distant stars, they said. While they had expected mostly microscopic samples, the researchers said, a surprising number of the particles were large enough to be seen with the naked eye. "It exceeded all of our grandest expectations," Donald Brownlee of the...

COLUMBIA, S.C. - A supernova could be the "quick and dirty" explanation for what may have happened to an early North American culture, a nuclear scientist here said Thursday. Richard Firestone said at the "Clovis in the Southeast" conference that he thinks "impact regions" on mammoth tusks found in Gainey, Mich., were caused by magnetic particles rich in elements like titanium and uranium. This composition, the Lawrence Berkeley National Laboratory scientist said, resembles rocks that were discovered on the moon and have also been found in lunar meteorites that fell to Earth about 10,000 years ago. Firestone said that, based...

Houston Comets forward Sheryl Swoopes is opening up about being a lesbian, telling a magazine that she's "tired of having to hide my feelings about the person I care about." Swoopes, honored last month as the WNBA's Most Valuable Player, told ESPN The Magazine for a story on newsstands today that she didn't always know she was gay and fears that coming out could jeopardize her status as a role model. "Do I think I was born this way? No," Swoopes said. "And that's probably confusing to some, because I know a lot of people believe that you are." Swoopes,...

Although comets form at the frigid edges of the solar system, they appear somehow to contain minerals that form only in the presence of liquid water, and at much warmer temperatures, scientists are reporting today. On July 4, as planned, part of the Deep Impact spacecraft - essentially an 820-pound, washing machine-size bullet - slammed into the comet Tempel 1 at 23,000 miles an hour. The collision tossed up thousands of tons of ice and dust from the comet that were observed by telescopes on Earth as well as small flotilla of spacecraft. One of the observers was the Spitzer...

THUNDERBOLTS PICTURE OF THE DAYExploring the electric universe From ancient mythology to cosmic plasma discharge   homethe book quotes picture of the day picture archive subject index the film(video clips) products Contact usElectric Universe: Holoscience Electric Cosmos The Universe Dragon Science Plasma Cosmology Society for Interdisciplinary Studies     Jul 05, 2005Deep Impact?First ImpressionsThe Deep Impact was an amazing show, and there will be much more information to come.In advance of the event we set forth our expectations as explicitly as possible. Therefore, we urge readers of this page to refer to our previous Picture of the Day.We also...

WASHINGTON, July 4 -- NASA's Deep Impact spacecraft lived up to its name early Monday when it slammed into a comet with such force that the resulting blast of icy debris stunned scientists with its size and brightness. With the flyby stage of the two-part spacecraft watching from a safe distance, an 820-pound, copper-core "impactor" craft smashed into the nucleus of comet Tempel 1 at 23,000 miles per hour, sending a huge, bright spray of debris into space. "The impact was spectacular," said Dr. Michael A'Hearn of the University of Maryland, the projects principal scientist. "It was much brighter than...

THUNDERBOLTS PICTURE OF THE DAYExploring the electric universe From ancient mythology to cosmic plasma discharge Credit: NASA/JPL/UMD Artwork by Pat Rawlings the book quotes picture of the day picture archive subject index the film(video clips) products Contact usElectric Universe: Holoscience Electric Cosmos The Universe Dragon Science Plasma Cosmology Society for Interdisciplinary Studies     Jul 04, 2005Predictions on "Deep Impact"With the imminent arrival of the "Deep Impact" spacecraft at the comet Tempel 1, it is time to test competing theories on the nature of comets. The predictions and lines of reasoning offered here will set the stage for future...

WASHINGTON, June 27 - A two-stage spacecraft called Deep Impact is about to make an ambitious attempt to dissect a comet by slamming into it and blowing some of its innards into space for all to see. Launched from Florida on Jan. 12, NASA's Deep Impact is nearing the end of a finely calibrated 268-million-mile journey that puts comet Tempel 1 within its sights. An 820-pound copper-core "impactor" is to smash into the comet's nucleus at 23,000 miles an hour in the early hours of July 4, an unprecedented event that will, if all goes well, be witnessed by its...

On 26 May, JPL's unique orbital calculation software determined that Comet Catalina was on what could possibly be a collision course with Earth, though the odds of such an impact were small: just 1 chance in 300,000 of a strike on June 11, 2085. Based on the 980-metre size estimate, that would produce a 6-gigaton impact - equivalent to 6 billion tonnes of TNT. Astronomers expected the addition of further observations to the calculations to rule out any possibility of a collision, as happens with most newly-seen objects. But that did not quite happen. The comet's predicted pathway actually drew...

CAPE CANAVERAL, Fla. — A NASA spacecraft with a Hollywood name — Deep Impact — blasted off today on a mission to smash a hole in a comet and give scientists a glimpse of the frozen primordial ingredients of the solar system. With a launch window only one second long, Deep Impact rocketed away at the designated moment on a six-month, 268-million-mile journey to Comet Tempel 1. It will be a one-way trip that NASA hopes will reach a cataclysmic end on the Fourth of July. "We are on our way," an excited Michael A'Hearn of the University of Maryland,...

WASHINGTON, Jan. 10 - Since the earliest days of the solar system, comets have periodically smashed into Earth, blasting holes in the surface and scattering cosmic debris. Now it is our turn to strike back. On Wednesday, NASA is to launch a spacecraft called Deep Impact toward the comet Tempel 1. In six months, if all goes well, the craft will release an 820-pound copper-core "impactor" that will smash into the comet's nucleus at 23,000 miles per hour, excavating a crater that scientists say could be as large as a sports coliseum. Launching of the spacecraft from the Cape Canaveral...

Microscopic analysis, reported in the current issue of the journal Geology, revealed a 3-inch-thick layer of "shocked quartz" — a form of the mineral produced only under intense pressure like that of an impact — that dated to 35.5 million years ago, when a space rock slammed into the Earth about 120 miles southeast of present-day Washington.

IF IT had hit Central London, Britain would no longer have a capital city. The force of the meteorite that hit eastern Siberia last September destroyed 40 square miles of forest and caused earth tremors felt 60 miles away. An expedition from Russia's Kosmopoisk institute has only recently reached the site in a remote area north of Lake Baikal because of bad weather and difficult terrain, the Interfax news agency said yesterday. Fragments of the meteorite had apparently exploded into shrapnel 18 miles above the Earth with the force of at least 200 tonnes of TNT. At the time, Russian...

Members of a special expedition researching the site of the famous Tunguska meteorite fall have claimed they had discovered parts of an extraterrestrial device. The expedition, organized by the Siberian Public State Foundation “Tunguska Space Phenomenon” completed its work on the scene of Tunguska meteorite fall on August 9. It was the first expedition to the region since 2000. Guided by the space photos, the researchers scanned a wider territory in the vicinity of the Poligusa village for parts of the space object that crashed into Earth in 1908 and was later called the Tunguska meteorite. The scientists claim that...

Picture credit: TheCabal"I will never cower before any master nor bend to any threat"LINK TO THREAD TEN Iran seeks swap of Brits for suicide attackers Report says 40 Revolutionary Guard 'volunteers' held by UK Iran apprehended British military personnel and Navy vessels earlier this week in order to secure release of 40 "suicide operations volunteers" held by the UK, according to an Iranian Revolutionary Guard source. The source told the London Arabic-language daily Al-Sharq Al-Awsat that the British Army command in Iraq received the demand from the Revolutionary Guard, reported the Middle East Media Research Institute. According to the source,...

GREETINGS, FOLLOWING is a note re todays Alaskan quake. First a comment about this thread. SOME FREEPERS are fascinated with fringe areas of reality. Some of us even think the fringe areas of knowledge, research, anecdotal stories and the like will have very impactful effects on the WAR ON TERROR, WWIII, Biblical end time events etc. WE ALSO FIND FREEPERS FULL OF GREAT CREATIVITY OF THOUGHT, INSIGHT, WORK RELATED EXPERIENCES AND SKILLS ETC. useful in collecting diverse puzzle pieces and in analyzing them. This diversity is priceless and virtually unavailable on any other site. While we are seriously interested in...

Did comets flood Earth’s oceans? Did comets flood Earth's oceans? 16 June 2004 Did the Earth form with water locked into its rocks, which then gradually leaked out over millions of years? Or did the occasional impacting comet provide the Earth’s oceans? The Ptolemy experiment on Rosetta may just find out… The Earth needed a supply of water for its oceans, and the comets are large celestial icebergs - frozen reservoirs of water orbiting the Sun. Did the impact of a number of comets, thousands of millions of years ago, provide the Earth with its supply of water? Finding hard...

Comets to put on morning sky show By Dr David Whitehouse BBC News Online science editor Comet Bradfield passes the Sun Astronomers say there could be three comets visible to the unaided eye in the night sky in a few weeks' time. Comet Bradfield has just rounded the Sun and is heading for the dawn sky. It will be visible around 24 April. Comet Linear, too, is promising and should be seen at northern latitudes in the morning sky on about the same date. Finally, Comet Neat may be visible though experienced observers say it will be a week or...

The Mars rover Opportunity's examination of Martian rocks last week provided the first convincing evidence that our neighbour world was once "awash" in water, as one NASA scientist described it. But where did the water come from? And why does Mars have no liquid water now, while Earth apparently has been covered with the stuff for 4 billion years? Scientists are just beginning to piece the story together, and it goes right back to the beginning. Mars, like Earth, was formed from dusty and rocky debris left over after the sun was born 4.57 billion years ago. Initially, there were...