Bright meteor captured on a webcam in Portsmouth, New Hampshire on May 17, 2016. Via www.portsmouthwebcam.com
It came from outer space—literally! On Tuesday, May 17, 2016, the early morning sky briefly lit up with the brilliant flash of a fireball—that is, an extremely bright meteor—over much of eastern New England states and even parts of southeastern Canada.
The event, which occurred around 12:50 a.m. EDT (04:50 UTC), was reported by witnesses from Maine, New Hampshire, Massachusetts, Rhode Island, Connecticut, New York, Ontario, and Québec, and captured on several automated cameras like a webcam in Portsmouth, NH (seen above) and a police dashcam in Plattsburgh, NY (below).
The fireball appeared to be moving from southwest to northeast and for some witnesses created an audible sonic boom, heard (and felt) several minutes later.
Meteors are the result of debris in space rapidly entering Earth’s upper atmosphere, compressing the air and causing it to quickly release energy in the form of heat and optical light. If the entering object is massive enough it may violently disintegrate during its fall, creating both light and sound. This particular meteor technically classifies as a bolide, due to its brightness, eruption, and visible fragmentation. Learn more about the various types of meteors here.
No reports of a meteorite impact at ground level have been made although I must assume there will be individuals who go on the hunt—meteorite fragments, especially those associated with witnessed events, can be quite valuable.
Full-frame image of the May 17, 2016 meteor from Portsmouth, NH (portsmouthwebcam.com)
Did you witness the event or capture it on camera? Report your sighting of this or any other fireballs on the AMS siteand be sure to send your fireball videos or images to the American Meteor Society here.
Pentax K-1000, 50mm lens, Kodak Ektar 100
Exposure ~ 8 seconds at Dusk,
Capturing a Bright Fireball, breaking up with debri,
Yellow Springs, Ohio. Photo credit: John Chumack
Last Saturday, Feb. 6th, a meteorite reportedly struck a bus driver on the campus of the Bharathidasan Engineering College in southern India. Three students were also injured and several windows were shattered in some kind of explosion. Online videos and stills show a small crater left by the impact. If true, this would be the first time in recorded history a person was struck and killed by a meteorite.
Meteorite or …?
Call me skeptical. Since the purported meteorite weighed about 50 grams — just under two ounces — it would be far too small to cause an explosion or significant impact crater five feet deep and two feet wide as depicted in both video and still photos. There were also no reports of rumbles, sonic booms or sightings of a fireball streaking across the sky, sights and sounds associated with material substantial enough to penetrate the atmosphere and plunge to the ground. Shattered windows would indicate an explosion similar to the one that occurred over Chelyabinsk, Russia in February 2013. The blast wave spawned when the Russian meteorite fractured into thousands of pieces miles overhead pulverized thousands of windows with flying glass caused numerous injuries.
According to a story that ran in The News Minute, a team led by the Indian Space Research Organization (IRSO) recovered an object 2 cm (3/4 inch) in width that weighed 50 grams and looked like a meteorite with “air bubbles on its rigid surface”. There’s also been chatter about meteor showers dropping meteorites to Earth, with various stories reporting that there no active meteor showers at the time of the driver’s death. For the record, not a single meteorite ever found has been linked to a shower. Dust and tiny bits of comets produce most shower meteors, which vaporize to fine soot in the atmosphere.
Now even NASA says that based on images posted online, the explosion is “land based” rather than a rock from space.
There have been close calls in the past most notably in Sylacauga, Alabama On November 30, 1954 at 2:46 p.m. an 8.5 lb rock crashed through the roof of a home not far from that town, hit a radio console, bounced off the floor and struck the hand and hip of 31-year-old Ann Hodges who was asleep on the couch at the time. She awoke in surprise and pain thinking that a space heater had blown up. But when she noticed the hole in the roof and a rock on the floor, Hodges figured the neighborhood kids had been up to no good.
Dr. Moody James shows where Ann Hodges was struck in the hip by an 8.5 lb meteorite that crashed through her roof (right). The photos appeared in the Dec. 13, 1954 issue of Life magazine. Photo by Jay Leviton, Time & Life Pictures, Getty Images
Fortunately her injuries weren’t serious. Ann became a sudden celebrity; her photo even appeared on the cover of Life magazine with a story titled “A Big Bruiser From The Sky”. In 1956 she donated the meteorite to the Alabama Museum of Natural History in Tuscaloosa, where you can still see it to this day. A second meteorite from the fall weighing 3.7 lbs. was picked up the following day by Julius K. McKinney in the middle of a dirt road. McKinney sold his fragment to the Smithsonian and used the money to purchase a small farm and used car.
Claims of people getting hit by meteorites have been on the increase in the past few years with the growth of the social media. Some stories have been deliberately made up and none have been verified. This would appear to be another tall tale if only based upon the improbabilities. In the meantime I’ve dug around and discovered another story that’s more probable and may indeed be the truth, though I have no way as of yet to independently verify it.
Police at the college say that two of the school’s gardeners were burning materials from the garden when the fire inadvertently set off sticks of dynamite that had been abandoned “amid the rocks” when the college was first built. The driver, by the name of Kamaraj and another driver, Sultan, were drinking water nearby when they were hit by the shrapnel and flying glass. Kamaraj began bleeding and was rushed to a hospital but died on the way. More HERE.
In the meantime, we only hope officials get to the bottom of the tragic death.
Various meteorites from 2008 TC3.
Credit: P. Jenniskens, et. al. Click image for full description
Asteroids, meteors, and meteorites … It might be fair to say these rocks from space inspire both wonder and fear among us Earthlings. But knowing a bit more about each of them and how they differ may eliminate some potential misgivings. While all these rocks originate from space, they have different names depending their location — i.e. whether they are hurtling through space or hurtling through the atmosphere and impacting Earth’s surface.
In simplest terms here are the definitions:
Asteroid: a large rocky body in space, in orbit around the Sun.
Meteoroid: much smaller rocks or particles in orbit around the Sun.
Meteor: If a meteoroid enters the Earth’s atmosphere and vaporizes, it becomes a meteor, which is often called a shooting star.
Meteorite: If a small asteroid or large meteoroid survives its fiery passage through the Earth’s atmosphere and lands on Earth’s surface, it is then called a meteorite.
Another related term is bolide, which is a very bright meteor that often explodes in the atmosphere. This can also be called a fireball.
Let’s look at each in more detail:
Asteroids An artists impression of an asteroid belt. Credit: NASA
Asteroids are found mainly in the asteroid belt, between Mars and Jupiter. Sometimes their orbits get perturbed or altered and some asteroids end up coming closer to the Sun, and therefore closer to Earth. In addition to the asteroid belt, however, there have been recent discussions among astronomers about the potential existence of large number asteroids in the Kuiper Belt and Oort Cloud. You can read a paper about this concept here, and a good article discussing the topic here.
The asteroid Vesta as seen by the Dawn spacecraft. Credit: NASA/JPL-Caltech/UCAL/MPS/DLR/IDA
Asteroids are sometimes referred to as minor planets or planetoids, but in general, they are rocky bodies that do not have an atmosphere. However, a few have their own moons. Our Solar System contains millions of asteroids, many of which are thought to be the shattered remnants of planetesimals – bodies within the young Sun’s solar nebula that never grew large enough to become planets.
The size of what classifies as an asteroid is not extremely well defined, as an asteroid can range from a few meters wide – like a boulder — to objects that are hundreds of kilometers in diameter. The largest asteroid is asteroid Ceres at about 952 km (592 miles) in diameter, and Ceres is so large that it is also categorized as a dwarf planet.
Most asteroids are made of rock, but as we explore and learn more about them we know that some are composed of metal, mostly nickel and iron. According to NASA, a small portion of the asteroid population may be burned-out comets whose ices have evaporated away and been blown off into space. Recently, astronomers have discovered some asteroids that mimic comets in that gas and dust are emanating from them, and as we mentioned earlier, there appears to be a large number of bodies with asteroid-like compositions but comet-like orbits.
How Often Do Asteroids Hit Earth?
Meteor Crater near Winslow, Arizona. Image credit: NASA.
While we know that some asteroids pass very close to Earth’s orbit around the Sun, we’ve been lucky in the history of humanity that we haven’t had a large asteroid hit Earth in the past several thousand years. It wasn’t until satellite imagery of Earth became widely available that scientists were able to see evidence of past asteroid impacts.
One of the more famous impact craters on Earth is Meteor Crater in Arizona in the US, which was made by an impact about 50,000 years ago. But there are about 175 known impact around the world – a few are quite large, like Vredefort Crater in South Africa which has an estimated radius of 190 kilometers (118 miles), making it the world’s largest known impact structure on Earth. Another notable impact site is off the coast of the Yucatan Peninsula in Mexico, and is believed to be a record of the event that led to the extinction of the dinosaurs 65 million years ago. You can see images of some of the most impressive Earth impact craters here.
These days, asteroid impacts are less of a threat. NASA estimates that about once a year an automobile-sized asteroid enters Earth’s atmosphere, creates an impressive fireball and disintegrates before ever reaching the surface. Studies of Earth’s history indicate that about once every 5,000 years or so on average an object the size of a football field hits Earth and causes significant damage. Once every few million years on average an object large enough to cause regional or global disaster impacts Earth. You can find more information about the frequency of impacts in this article from NASA.
Meteors, Meteoroids and Bolides
A bright meteor from September 21, 1994. Credit: John Chumack.
Space debris smaller than an asteroid are called meteoroids. A meteoroid is a piece of interplanetary matter that is smaller than an asteroid and frequently are only millimeters in size. Most meteoroids that enter the Earth’s atmosphere are so small that they vaporize completely and never reach the planet’s surface. When they burn up during their descent, they create a beautiful trail of light known as a meteor, sometimes called a shooting star.
Mostly these are harmless, but larger meteors that explode in the atmosphere – sometimes called bolides — can create shockwaves, which can cause problems. In February 2013 a meteor that exploded over Chelyabinsk, Russia shattered windows with its air blast. This meteoroid or bolide was estimated to be 18 meters (59 feet) in diameter. In 1908, a rocky meteoroid less than 100 meters in diameter is believed to have entered the atmosphere over the Tunguska region of Siberia in 1908 and the resulting shockwave knocked down trees for hundreds of square kilometers
How often is Earth hit by meteroids?
Chelyabinsk fireball recorded by a dashcam from Kamensk-Uralsky north of Chelyabinsk where it was still dawn.
Because of the Chelyabinsk meteor in 2013, astronomers have acquired more information about the frequency of larger meteors that hit Earth, and there is now a growing consensus that the Earth gets hit by bigger space rocks more often than we previously thought. You can read more about that concept here.
This video from the B612 Foundation shows a visualization of the location of 26 space rocks that hit Earth between 2000 and 2013, each releasing energy equivalent to some of our most powerful nuclear weapons. The B612 foundation says that a Hiroshima-scale asteroid explosion happens in our atmosphere on average once a year, but many are not detected because they explode high in the atmosphere, or because most of the Earth’s surface is water and even a large percentage of land is fairly uninhabited by humans.
Estimates vary of how much cosmic dust and meteors enter Earth’s atmosphere each day, but range anywhere from 5 to 300 metric tons. Satellite observations suggest that 100-300 metric tons of cosmic dust enter the atmosphere each day. This figure comes from the rate of accumulation in polar ice cores and deep-sea sediments of rare elements linked to cosmic dust, such as iridium and osmium.
But other measurements – which includes meteor radar observations, laser observations and measurements by high altitude aircraft — indicate that the input could be as low as 5 metric ton per day. Read more about this here.
For a documented list of bolide events, you can check out this page from JPL.
Meteorite A stunning slice of the Glorieta pallasite meteorite cut thin enough to allow light to shine through its many olivine crystals. Credit: Mike Miller
If any part of a meteoroid survives the fall through the atmosphere and lands on Earth, it is called a meteorite. Although the vast majority of meteorites are very small, their size can range from about a fraction of a gram (the size of a pebble) to 100 kilograms (220 lbs) or more (the size of a huge, life-destroying boulder). Meteorites smaller than 2mm are classified as micrometeorites.
Meteorites have traditionally been divided into three broad categories, depending on their structure, chemical and isotopic composition and mineralogy. Stony meteorites are rocks, mainly composed of silicate minerals; iron meteorites that are largely composed of metallic iron-nickel; and, stony-iron meteorites that contain large amounts of both metallic and rocky material.
Meteorites have also been found on the Moon and Mars and conversely, scientists have traced the origination of the meteorites found here on Earth to four other bodies: the Moon, Mars, the asteroid 4 Vesta, and the comet Wild 2. Meteorites are the source of a great deal of the knowledge that we have have about the composition of other celestial bodies.
How Often Do Meteorites Hit Earth?
On Feb. 28, 2009, Peter Jenniskens (SETI/NASA), finds his first 2008TC3 meteorite after an 18-mile long journey. “It was an incredible feeling,” Jenniskens said. The African Nubian Desert meteorite of Oct 7, 2008 was the first asteroid whose impact with Earth was predicted while still in space approaching Earth. 2008TC3 and Chelyabinsk are part of the released data set. (Credit: NASA/SETI/P.Jenniskens)
According to the Planetary Science Institute, it is estimated that probably 500 meteorites reach the surface of the Earth each year, but less than 10 are recovered. This is because most fall into water (oceans, seas or lakes) or land in remote areas of the Earth that are not accessible, or are just not seen to fall.
In short, the difference between asteroids and meteors all comes down to a question of location. Asteroids are always found in space. Once it enters an atmosphere, it becomes a meteor, and then a meteorite after it hits the ground. Each are made of the same basic materials – minerals and rock – and each originated in space. The main difference is where they are when they are being observed.
Aerial photo of the crater site, taken with the Polar 6 board camera, while the aircraft was flying 7000 feet above the ice shelf. Credit: Alfred-Wegener-Institut
Ever since its discovery was announced earlier this year, the 3 km-wide ring structure discovered on the of Antarctica has been a source of significant interest and speculation. Initially, the discovery was seen as little more than a happy accident that occurred during a survey of East Antarctica by a WEGAS (West-East Gondwana Amalgamation and its Separation) team from the Alfred Wegener Institute.
However, after the team was interviewed by the Brussels-based International Polar Foundation, news of the find and its possible implication spread like wildfire. Initial theories for the possible origin of the ring indicated that it could be the result of the impact of a large meteor. However, since the news broke, team leader Olaf Eisen has offered an alternative explanation: that the ring structure is in fact the result of other ice-shelf processes.
As Eisen indicated in a new entry on the AWI Ice Blog: “Doug MacAyeal, glaciologist from the University of Chicago, put forward the suggestion that the ring structure could be an ice doline.” Ice dolines are round sinkholes that are caused by a pool of melt water formed within the shelf ice. They are formed by the caving in of ice sheets or glaciers, much in the same way that sinkholes form over caves.
“If the melt water drains suddenly,” he wrote, “like it often does, the surface of the glacier is destabilised and does collapse, forming a round crater. Ice depressions like this have been observed in Greenland and on ice shelves of the Antarctic Peninsula since the 1930s.”
Aerial photo of the ringed formation that the AWI researchers found on the Antarctic ice shelf. Credit: Tobias Binder, AWI
However, in glaciers, these cavities form much more rapidly, as the meltwater created by temperature variations causes englacial lakes or water pockets to from which then drains through the ice sheet. Such dolines have been observed for decades, particularly in Greenland and the Antarctic Peninsula where the ice melts during the summertime.
Initial analysis of satellite images appear to confirm this, as they indicate that the feature could have been present before the supposed impact took place around 25 years ago. In addition, relying on data from Google Maps and Google Earth, the WEGAS (West-East Gondwana Amalgamation and its Separation) team observed that the 3 km ring is accompanied by other, smaller rings.
Such formations are inconsistent with meteorite impacts, which generally leave a single crater with a raised center. And as a general rule, these craters also measure between ten to twenty times the size of the meteorite itself – in this case, that would mean a meteorite 200 meters in diameter. This would mean that, had the ring structure been caused by a meteorite, it would have been the largest Antarctic meteor impact on record.
It is therefore understandable why the announcement of this ring structure triggered such speculation and interest. Meteorite impacts, especially record-breaking ones are nothing if not a hot news item. Too bad this does not appear to be the case.
Location of the ring formation on the King Baudouin Ice Shelf off the Antarctic continent. Credit: Google Maps, NOAA
However, the possibility that the ring structure is the result of an ice doline raises a new host of interesting questions. For one, it would indicate that dolines are much more common in East Antarctica than previously thought. Ice dolines were first noticed in the regions of West Antarctica and the Antarctic Peninsula, where rapid warming is known to take place.
East Antarctica, by contrast, has long been understood to be the coldest, windiest and driest landmass on the planet. Knowing that such a place could produce rapid warming that would lead to the creation of a significant englacial lake would certainly force scientists to rethink what they know about this continent.
“To form an ice doline this size, it would need a considerable reservoir of melt water,” Eisen said. “Therefore we would need to ask, where did all this melt water come from? Which melting processes have caused such an amount of water and how does the melting fit into the climate pattern of East Antarctica?”
In the coming months, Eisen and the AWI scientists plant to analyze the data from the Polar 6 (Eisen’s mission) measurements thoroughly, in the hopes of getting all the facts straight. Also, Jan Lenaerts – a Belgian glaciologist with AWI – is planning an land-based expedition to the site; which unfortunately due to the short Antarctic summer season and the preparation time needed won’t be taking place until the end of 2015.
AWI’s Polar 6 aircraft takes off from the runway at the Princess Elisabeth Antarctica research station. Credit: International Polar Foundation / Jos Van Hemelrijck
But what is especially interesting, according to Eisen, is the rapid pace at which the debate surrounding the ring structure occurred. Within days of their announcement, the WEGAS team was astounded by the nature of the debate taking place in the media and on the internet (particularly Facebook), bringing together glaciologists from all around the world.
As Eisen put it in his blog entry, “For the WEGAS team, however, our experience of the last few days has shown that modern scientific discussion is not confined to the ivory towers of learned meetings, technical papers, and lecture halls, but that the public and social media play a tremendous role. For us, cut off from the modern world amongst the eternal ice, this new science seems to have happened at an almost breathtaking pace.”
This activity brought the discussion about the nature of the ring structure forward by several weeks, he claims, focusing attention on the true causes of the surprise discovery itself and comparing and contrasting possible theories.
Mars! Martian meteorites make their way to Earth after being ejected from Mars by a meteor impact on the Red Planet. Image: NASA/National Space Science Data Center.
Mars is often referred to as the Red Planet. But its signature color is only skin-deep – or, I should say, dust-deep. Beneath its rusty regolith Mars has many other hues and shades as well, from pale greys like those found inside holes drilled by Curiosity to large dark regions that are the result of ancient lava flows. Now, researchers think we may have an actual piece of one of Mars’ dark plains here on Earth in the form of a meteorite that was found in the Moroccan desert in 2011.
Mars meteorite NWA 7034 (NASA)
Classified as NWA 7034 (for Northwest Africa) the meteorite is a 320-gram (11 oz.) piece of Martian basaltic breccia made up of small fragments cemented together in a dark matrix. Nicknamed “Black Beauty,” NWA 7034 is one of the oldest meteorites ever discovered and is like nothing else ever found on Earth.
According to a new study on a fragment of the meteorite by researchers from Brown University in Providence, Rhode Island and the University of New Mexico, Black Beauty is a 4.4-billion-year-old chunk of Mars’ dark crust – the only known piece of such to have landed on Earth.
While other meteorites originating from Mars have been identified, they are of entirely different types than Black Beauty.
The researchers used a hyperspectral imaging technique to obtain data from across the whole fragment. In doing this, the measurements matched what’s been detected from Mars orbit by NASA’s Mars Reconnaissance Orbiter.
“Other techniques give us measurements of a dime-sized spot,” said Kevin Cannon, a Brown University graduate student and lead author of a new paper published in the journal Icarus. “What we wanted to do was get an average for the entire sample. That overall measurement was what ended up matching the orbital data.”
In addition to indicating a truly ancient piece of another planet, these findings hint at what the surface of many parts of Mars might be like just below the rusty soil… a surface that’s been shattered and reassembled many times by meteorite impacts.
“This is showing that if you went to Mars and picked up a chunk of crust, you’d expect it to be heavily beat up, battered, broken apart and put back together,” Cannon said.
HiRISE image of dark terrain near Ganges Chasma (NASA/JPL/University of Arizona)
A discovery photo of the ringed formation, 2km (1.24 miles) that AWI researchers are proposing is a meteorite impact site. (Credit:Tobias Binder, AWI)
Endless blinding white ice as far as the eye can see. This is the common scene from the window of planes delivering researchers to Antarctica. However, this is not always the case. While there are mountain ranges and valleys, for a recent research expedition, a large ringed structure came into view on the King Baudouin ice shelf as they were beginning aerial surveys.
Geophysicist Christian Mueller with the Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) in Germany, was looking out the window of an instrument laden plane when the previously unknown ringed formation, 2000 meters (1.24 miles) in diameter, came into view. Looking into research publications, he found evidence that this may be a meteorite impact event from 2004.
Research team members from Alfred Wegener Institute in Germany embark from a landing site at Princess Elisabeth, Antarctica. They discovered something totally unexpected – a large ringed formation on a nearby ice shelf. (Credit: AWI)
The discovery occurred on December 20th from the AWI Polar 6 aircraft as they were flying over the Princess Ragnhild Coast. The formation is located on the King Baudouin Ice Shelf not far from their landing site at Princess Elizabeth station.
Two studies were found in the literature by the researchers which pointed to a possible impact event over east Antarctica in 2004. Triangulation of infrasound monitoring data pointed to the area where the ringed formation is located. The infrasound monitoring sites are located worldwide and primarily used to detect nuclear testing events. On February 15, 2013, the same type of data was used to better understand the asteroid explosion over Chelyabinsk, Russia.
Location of the ring formation on the ice shelf off the Antarctic continent. The site is on the King Baudouin Ice Shelf. (Map Credits: Google Maps, NOAA)
The second study involved local observations. A separate set of researchers, located at Davis Station, an Australian base off the coast of east Antarctica, reported seeing a dust trail in the upper atmosphere during the same time.
Researcher Mueller stated in the AWI provided video, “I looked out of the window, and I saw an unusual structure on the surface of the ice. There was some broken ice looking like icebergs, which is very unusual on a normally flat ice shelf, surrounded by a large, wing-shaped, circular structure.” Altogether, the AWI researchers said that they make the claim “without any confidence.” They intend to request funding to make followup studies to determine its origin.
Cheryl Santa Maria, of the Digital Reporter, also reported that there are survey images showing this structure that date back 25 years. Furthermore, a story by LiveScience quoted Dr. Peter Brown of Centre of Planetary Science and Exploration at the University of Western Ontario as stating that the size of a meteorite is roughly 5 to 10% of the impact crater’s diameter. This would indicate an impactor about 100 meters in size and much larger than the estimated size of the event as estimated by infrasound data from 2004.
The infrasound data estimated that the asteroid was probably the size of a house, about 10 meters (33 feet) across. In contrast, the asteroid that exploded over Chelyabinsk, Russia, had an estimated size of 20 meters. Dr. Brown was quoted as expressing doubt that the formation is an impact site. The effects of a 100 meter object would have been much more distinctive and likely more readily detected by researchers located in eastern Antarctica. Thus, reporting of the ring formation by the AWI researchers is bringing to light additional information and comments from experts that raises doubts. Follow up studies will be necessary to determine the true origins of the ringed structured.
The idea that Mars could have supported life at one time is the subject of ongoing debate. Image credit: NASA
Mars is currently home to a small army robotic rovers, satellites and orbiters, all of which are busy at work trying to unravel the deeper mysteries of Earth’s neighbor. These include whether or not the planet ever had liquid water on its surface, what the atmosphere once looked like, and – most importantly of all – if it ever supported life.
And while much has been learned about Martian water and its atmosphere, the all-important question of life remains unanswered. Until such time as organic molecules – considered to be the holy grail for missions like Curiosity – are found, scientists must look elsewhere to find evidence of Martian life.
According to a recent paper submitted by an international team of scientists, that evidence may have arrived on Earth three and a half years ago aboard a meteorite that fell in the Moroccan desert. Believed to have broken away from Mars 700,000 years ago, so-called Tissint meteorite has internal features that researchers say appear to be organic materials.
The paper appeared in the scientific journal Meteoritics and Planetary Sciences. In it, the research team – which includes scientists from the Swiss Federal Institute of Technology in Lausanne (EPFL) – indicate organic carbon is located inside fissures in the rock. All indications are the meteorite is Martian in origin.
“So far, there is no other theory that we find more compelling,” says Philippe Gillet, director of EPFL’s Earth and Planetary Sciences Laboratory. He and his colleagues from China, Japan and Germany performed a detailed analysis of organic carbon traces from a Martian meteorite, and have concluded that they have a very probable biological origin.
Artist’s conception of an fragment as it blasts off from Mars as a result of a meteor impact. Credit: The Planetary Society
The scientists argue that carbon could have been deposited into the fissures of the rock when it was still on Mars by the infiltration of fluid that was rich in organic matter.
If this sounds familiar, you may recall a previous Martian meteorite named ALH84001, found in the Allen Hills region in Antarctica. In 1996 NASA researchers announced they had found evidence within ALH84001 that strongly suggested primitive life may have existed on Mars more than 3.6 billion years ago. While subsequent studies of the now famous Allen Hills Meteorite shot down theories that the Mars rock held fossilized alien life, both sides continue to debate the issue.
This new research on the Tissint meteorite will likely be reviewed and rebutted, as well.
The researchers say the meteorite was likely ejected from Mars after an asteroid crashed on its surface, and fell to Earth on July 18, 2011, and fell in Morocco in view of several eyewitnesses.
Upon examination, the alien rock was found to have small fissures that were filled with carbon-containing matter. Several research teams have already shown that this component is organic in nature, but they are still debating where the carbon came from.
Chemical, microscopic and isotope analysis of the carbon material led the researchers to several possible explanations of its origin. They established characteristics that unequivocally excluded a terrestrial origin, and showed that the carbon content were deposited in the Tissint’s fissures before it left Mars.
This research challenges research proposed in 2012 that asserted that the carbon traces originated through the high-temperature crystallization of magma. According to the new study, a more likely explanation is that liquids containing organic compounds of biological origin infiltrated Tissint’s “mother” rock at low temperatures, near the Martian surface.
A piece of the Tissint meteorite that landed on Earth on July 18th, 2011. Credit: EPFL/Alain Herzog
These conclusions are supported by several intrinsic properties of the meteorite’s carbon, e.g. its ratio of carbon-13 to carbon-12. This was found to be significantly lower than the ratio of carbon-13 in the CO2 of Mars’s atmosphere, previously measured by the Phoenix and Curiosity rovers.
Moreover, the difference between these ratios corresponds perfectly with what is observed on Earth between a piece of coal – which is biological in origin – and the carbon in the atmosphere.
The researchers note that this organic matter could also have been brought to Mars when very primitive meteorites – carbonated chondrites – fell on it. However, they consider this scenario unlikely because such meteorites contain very low concentrations of organic matter.
“Insisting on certainty is unwise, particularly on such a sensitive topic,” warns Gillet. “I’m completely open to the possibility that other studies might contradict our findings. However, our conclusions are such that they will rekindle the debate as to the possible existence of biological activity on Mars – at least in the past.”
Be sure to check out these videos from EPFL News, which include an interview with Philippe Gillet, EPFL and co-author of the study:
And this video explaining the history of the Tissint meteor:
The Meteorite of Serooskerken (Source: Sterrenwacht Sonnenborgh)
Here’s a bit of good news: the Serooskerken meteorite, which was stolen from the Sonnenborgh Museum and Observatory in Utrecht, Netherlands on Monday night, has been recovered. It was found in a bag left in some bushes alongside a tennis court and turned in to the police.
It’s not quite “game, set, match” though; unfortunately the meteorite was broken during the theft. (See a photo here via Twitter follower Marieke Baan.) Still, the Sonnenborgh Museum director is glad to have the pieces back, which he said will remain useful for research and can still be exhibited. (Source)
The Serooskerken meteorite was recovered from a fall in the Dutch province of Zeeland on August 28, 1925. Classified as a diogenite (HED) it is thought to have originated from the protoplanet Vesta, the second most massive object in the main asteroid belt between the orbits of Mars and Jupiter (and the previous target of NASA’s Dawn mission.) It is one of only five meteorite specimens ever recovered in the Netherlands.
The meteorite was one of several items reported stolen from the Sonnenborgh Museum on the night of August 18-19, 2014.
The Meteorite of Serooskerken (Source: Sterrenwacht Sonnenborgh)
Calling all meteorite collectors and enthusiasts! There’s a hot space rock at large and, as Indiana Jones would say, it belongs in a museum. Perhaps you can help put it back in one.
Mosaic of the asteroid Vesta made from images acquired by NASA’s Dawn spacecraft. Credit: NASA/JPL-Caltech/UCAL/MPS/DLR/IDA
On Aug. 19 a burglary was reported at the Sonnenborgh Museum and Observatory in Utrecht, Netherlands, and one of the items missing is a meteorite that is thought to have originated from the asteroid Vesta.
Seen above in a photo from the museum’s collection, the Meteorite of Serooskerken was recovered from a rare fall in 1925 in the province of Zeeland. Only five meteorites have ever been found in the Netherlands, making the Serooskerken specimen somewhat of a national treasure – not to mention a valuable piece of our Solar System’s history!
About 5–6% of all the meteorites found on Earth are thought to be from Vesta, the second-largest world in the main asteroid belt. (Source)
It doesn’t sound like the meteorite was the target of the burglary, but rather it just happened to be included with other things taken from the museum’s safe.
