The crescent moon, Saturn and Mars will form a compact triangle in the southwestern sky in this evening August 31st. 3.5º separate the moon and Saturn; Mars and Saturn will be 5º apart. Stellarium
Check it out. Look southwest at dusk tonight and you’ll see three of the solar system’s coolest personalities gathering for a late dinner. Saturn, Mars and the waxing crescent moon will sup in Libra ahead of the fiery red star Antares in Scorpius. All together, a wonderful display of out-of-this-world worlds.
Four dark lunar seas, also called ‘maria’ (MAH-ree-uh), pop out in binoculars. Four featured craters are also highlighted – the triplet of Theophilus, Cyrillus and Catharina and Maurolycus, named after Francesco Maurolico, a 16th century Italian scientist. Credit: Virtual Moon Atlas / Christian LeGrande, Patrick Chevalley
If you have binoculars, take a closer look at the thick lunar crescent. Several prominent lunar seas, visible to the naked eye as dark patches, show up more clearly and have distinctly different outlines even at minimal magnification. Each is a plain of once-molten lava that oozed from cracks in the moon’s crust after major asteroid strikes 3-3.5 billion years ago.
Larger craters also come into view at 10x including the remarkable trio of Theophilus, Cyrillus and Catharina, each of which spans about 60 miles (96 km) across. Even in 3-inch telescope, you’ll see that Theophilus partly overlaps Cyrillus, a clear indicator that the impact that excavated the crater happened after Cyrillus formed.
Close-up of our featured trio of craters. Sharpness indicates freshness. Comparing the three, the Theophilus impact clearly happened after the others. Craters gradually become eroded over time from micrometeorite impacts, solar wind bombardment, moonquakes and extreme day-to-night temperature changes. Credit: Damian Peach
Notice that the rim Theophilus crater is still relatively crisp and fresh compared to the older, more battered outlines of its neighbors. Yet another sign of its relative youth.
Astronomers count craters on moons and planets to arrive at relative ages of their surfaces. Few craters indicate a youthful landscape, while many overlapping ones point to an ancient terrain little changed since the days when asteroids bombarded all the newly forming planets and moons. Once samples of the moon were returned from the Apollo missions and age-dated, scientists could then assign absolute ages to particular landforms. When it comes to planets like Mars, crater counts are combined with estimates of a landscape’s age along with information about the rate of impact cratering over the history of the solar system. Although we have a number of Martian meteorites with well-determined ages, we don’t know from where on Mars they originated.
At least three different impact sequences are illustrated in this photo. Maurolycus appears to lie atop an older crater, while younger, sharp-rimmed craters pock its center and southern rim. Even a 3-inch telescope will show signs of all three ages. Credit: Damian Peach
Another crater visible in 10x binoculars tonight is Maurolycus (more-oh-LYE-kus), a great depression 71 miles (114 km) across located in the moon’s southern hemisphere in a region rich with overlapping craters. Low-angled sunlight highlighting the crater’s rim will make it pop near the moon’s terminator, the dividing line between lunar day and night.
Like Theophilus, Maurolycus overlaps a more ancient, unnamed crater best seen in a small telescope. Notice that Maurolycus is no spring chicken either; its floor bears the scares of more recent impacts.
Putting it all into context, despite their varying relative ages, most of the moon’s craters are ancient, punched out by asteroid and comet bombardment more than 3.8 billion years ago. To look at the moon is to see a fossil record of a time when the solar system was a terrifyingly untidy place. Asteroids beat down incessantly on the young planets and moons.
Despite the occasional asteroid scare and meteorite fall, we live in relative peace now. Think what early life had to endure to survive to the present. Deep inside, our DNA still connects us to the terror of that time.
End of flight fragmentation of the Nov. 18, 2012, fireball over the San Francisco Bay Area (shown in a horizontally mirrored image to depict the time series from left to right). The photographs were taken from a distance of about 40 miles (65 km). Image Credit: Robert P. Moreno Jr., Jim Albers and Peter Jenniskens
What’s the chance of that thump you just heard in your house was a meteorite hitting your roof? That was the case for one family in Novato, California during a fireball event that took place in the north bay area near San Francisco on October 17, 2012.
Researchers have now released new results from analysis of the meteor that fell to Earth, revealing that the “Novato meteorite” was part of numerous collisions over a span of 4 billion years.
There is nothing ordinary about a meteorite whether it just spent 4.4 billion years all alone or spent such time in a game of cosmic pinball, interacting with other small or large bodies of our Solar System. On any given night one can watch at least a couple of meteors overhead burning up, lighting up the sky but never reaching the Earth below. However, in less than two years, Dr. Peter Jenniskens, SETI Institute’s renowned meteor expert was effectively host to two meteorites within a couple hours drive from his office in Mountain View, California.
The first was the Sutter Mill meteorite, a fantastic carbonaceous chondrite full of organic compounds. The second was the Novato meteorite, identified as a L6 chondrite fragmental breccia. which is the focus of new analysis, to be released in a paper in the August issue of Meteoritics and Planetary Science. Early on, it was clear that this meteorite had been a part of a larger asteroidal parent body that had undergone impact shocks.
Analysis of the meteorite was spearheaded by Jenniskens who initially determined the trajectory and orbit of the meteoroid from the Cameras for Allsky Meteor Surveillance (CAMS) which he helped establish in the greater San Francisco bay area. Jenniskens immediately released information about the fireball to local news agencies to ask for the public’s help with the hopes of finding pieces of the meteorite. One resident recalled hearing something hit her roof, and with the help of neighbors, they investigated and soon found the first fragment in their backyard.
Finding fragments was the first step, and over a two year period, the analysis of the Novato meteorite was spread across several laboratories around the world with specific specialties.
Novato N04, found by Bob Verish. The fourth of six fragments of the Novato fireball recovered. Fusion crust from entry into the Earth’s atmosphere is clearly evident. A 1 centimeter cube is shown for size comparison. (Image Credit, B. Verish, cams.seti.org)
Dr. Jenniskens, along with 50 co-authors, have concluded that the Novato meteorite had been involved in more impacts than previously thought. Dr. Qingzhu Yin, professor in the Department of Earth and Planetary Sciences at the University of California, Davis stated, “We determined that the meteorite likely got its black appearance from massive impact shocks causing a collisional resetting event 4.472 billion years ago, roughly 64-126 million years after the formation of the solar system.”
The predominant theory of the Moon’s formation involves an impact of the Earth by a Mars-sized body. The event resulted in the formation of the Moon but also the dispersal of many fragments throughout the inner Solar System. Dr. Qingzhu Yin continued, “We now suspect that the moon-forming impact may have scattered debris all over the inner solar system and hit the parent body of the Novato meteorite.”
Additionally, the researcher discovered that the parent body of the Novato meteorite experienced a massive impact event approximately 470 million years ago. This event dispersed many asteroidal fragments throughout the Asteroid Belt including a fragment from which resulted the Novato meteorite.
The Novato meteorite strewn field determined by Dr. Jenniskens team’s analysis of CAMS allsky images. (Illustration Credit, P. Jenniskens, NASA, SETI – cams.seti.org)
The trajectory analysis completed earlier by Dr. Jenniskens pointed the Novato meteorite back to the Gefion asteroid family. Dr. Kees Welten, cosmochemist at UC Berkeley, was able to further pinpoint the time, drawing the conclusion, “Novato broke from one of the Gefion family asteroids nine million years ago.” His colleague at Berkeley, cosmochemist Dr. Kunihiko Nishiizumialso added, “but may have been buried in a larger object until about one million years ago.”
There was more that could be revealed about history of the Novato meteorite. Dr. Derek Sears a meteoriticist working for the Bay Area Environmental Research Institute in Sonoma, California and stationed at NASA Ames Reserach Center applied his expertise in thermoluminescence. Dr. Sears was involved in the analysis of Lunar regolith returned by the Apollo astronauts using this analysis method.
“We can tell the rock was heated, but the cause of the heating is unclear,” said Dr. Sears, “It seems that Novato was hit again.” As stated in the NASA press release, “Scientists at Ames measured the meteorites’ thermoluminescence – the light re-emitted when heating of the material and releasing the stored energy of past electromagnetic and ionizing radiation exposure – to determine that Novato may have had another collision less than 100,000 years ago.”
From this apparent final collision one hundred thousand years ago, the Novato meteoroid completed over 10,000 orbits of the Sun and with its final Solar orbit, intercepted the Earth, entering our atmosphere and mostly burning up over California. The meteoroid is estimated to have measured 14 inches across (35 cm) and have weighed 176 pounds (80 kg). What reached the ground likely amounted to less than 5 lbs. (~ 2 kg). Only six fragments were recovered and many more remain buried or hidden in Sonoma and Napa counties.
Besides the analysis that revealed the series of likely impact events in the meteoroids history, a team led by Dr. Dan Glavin from NASA Goddard Space Flight Center undertook analysis in search of amino acids, the building blocks of life. They detected non-protein amino acids in the meteorite that are very rare on Earth. Dr. Jenniskens emphasized that the quick recovery of the fragments by scores of individuals that searched provided pristine samples for analysis.
The impact dent on the rooftop of the Webber home in Novato. Luis Rivera points to the dent. (Image Credit, P.Jenniskens, L.Rivera, cams.seti.org)
Robert P. Moreno, Jr. in Santa Rosa, CA photographed the fireball in greatest detail with a high resolution camera. Several other photos were brought forward from other vantage points. Dr. Jenniskens stated, “These photographs show that this meteorite – now one of the best studied meteorites of its kind – broke in spurts, each time creating a flash of light as it entered Earth’s atmosphere.”
An animated gif of the series of photographs taken by Robert Moreno Jr. Click on the image to animate in full resolution. (Credit, R. Moreno Jr., NASA, SETI)
Numerous individuals and groups undertook the search for the Novato meteorite. Dr. Jenniskens trajectory analysis included a likely impact zone or strewn field. People from all walks of life roamed the streets, open fields and hillsides of the north bay in search of fragments. Despite organized searches by Dr. Jenniskens, it was the footwork from other individuals that led to finding six fragments and was the first step which led to these studies that add to the understanding of the early Solar System’s development.
For Dr. Jenniskens, Novato was part of a trifecta – the April 22, 2012, Sutter Mill meteorite in the nearby foothills of the Sierras, the Novato meteorite and the massive Chelyabinsk airburst event in Russia on February 15, 2013. Throughout this period, Dr. Jenniskens all-sky camera network continued to expand and record “falling stars” – meteors. The number of meteors recorded with calculated trajectories is now over 175,000. The SETI Institute researcher has been supported by NASA and personnel at the institute and ordinary citizens including amateur astronomers that have refined the methods for meteor orbital determination and estimating their size and mass. Several websites have compiled images and results for the Novato meteorite with Dr. Jenniskens’ – CAMS.SETI.ORG being most prominent.
Rubble piles are common among asteroids, as illustrated by this artist's conception of 2011 MD. Credit: NASA/JPL-Caltech
How do asteroids hold their rubble piles together? Previously, scientists said it was a combination of friction and gravity. But new observations of asteroid 1950 DA reveals something else is at work. The asteroid is rotating too quickly for gravity to keep it together, so what’s going on?
“We found that 1950 DA is rotating faster than the breakup limit for its density,” stated Ben Rozitis, a postdoctoral researcher at the University of Tennessee, Knoxville who led the research. “So if just gravity were holding this rubble pile together, as is generally assumed, it would fly apart. Therefore, interparticle cohesive forces must be holding it together.”
Image of asteroid 1950 DA. Credit: NASA
Cohesive forces refer to the act of individual molecules or particles sticking together. It’s the first time scientists have found this in action on an asteroid. Better yet, if confirmed in other asteroids this has implications for protecting Earth from a killer asteroid should one come our way.
If the threat turns out to be a loosely held together asteroid, an impact in just the right spot would break the single asteroid into many. (Of course, you’d want to make sure that the problem doesn’t end up turning into multiple smaller asteroids hitting Earth instead of a single large one.)
Now the researchers are interested in knowing if cohesive forces are also in action on Comet 67P/Churyumov–Gerasimenko — the comet being examined by Rosetta right now and in November, by the lander Philae.
Artist's concept of OSIRIS-REx at Bennu. (Credit: NASA/GSFC)
I love anything that attempts to provide a sense of scale about the Solar System (see here and here for even more examples) and this one brings us down past the Sun, planets, and moons all the way to asteroid size — specifically asteroid 101955 Bennu, the target of the upcoming OSIRIS-REx mission.
Created by the OSIRIS-REx “321Science!” team, consisting of communicators, film and graphic arts students, teens, scientists, and engineers, the video shows some relative scales of our planet compared to the Sun, and also the actual size of asteroid Bennu in relation to some familiar human-made structures that we’re familiar with. (My personal take-away from this: Bennu — one of those “half grains of sand” — is a rather small target!)
A NASA New Frontiers mission, OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) will launch in Sept. 2016 on a two-year journey to the asteroid 101955 Bennu. Upon arrival OSIRIS-REx will map Bennu’s surface and also measure the Yarkovsky effect, by which asteroids’ trajectories can change over time due to the small force exerted by radiant heat.
Artist's conception of early Earth after several large asteroid impacts, moving magma on to the surface. Credit: Simone Marchi/SwRI
In case you need a reminder that the solar system was a harsh place to grow up, the early Earth looks like it was in the middle of a shooting gallery in this model. The map that you see above shows a scenario for where researchers believe asteroids struck our planet about four billion to 4.5 billion years ago, which is very early in the Earth’s five-billion-year history.
The research reveals the surface of the Earth repeatedly being churned by these impacts as the young solar system came together, with small rocks gradually coalescing into planetesimals. Much of the leftover debris peppered the planets, including our own.
“Prior to approximately four billion years ago, no large region of Earth’s surface could have survived untouched by impacts and their effects,” stated Simone Marchi, who led the research and works at the Southwest Research Institute in Colorado.
“The new picture of the Hadean Earth emerging from this work has important implications for its habitability,” added Marchi, who is also senior researcher at NASA’s Solar System Exploration Research Virtual Institute.
In this dangerous early period, the researchers estimate the Earth was smacked by 1-4 asteroids or comets that were more than 600 miles (966 kilometers) wide — enough to wipe out life across the planet. They also believe that between 3-7 impactors were more than 300 miles (482 kilometers) wide, which would evaporate oceans across the world.
Artist’s conception of early Earth after several large asteroid impacts, moving magma on to the surface. Credit: Simone Marchi/SwRI
“During that time, the lag between major collisions was long enough to allow intervals of more clement conditions, at least on a local scale,” added Marchi. “Any life emerging during the Hadean eon likely needed to be resistant to high temperatures, and could have survived such a violent period in Earth’s history by thriving in niches deep underground or in the ocean’s crust.”
To produce the model, the researchers took a recent model of lunar impacts and applied it to Earth. The moon’s scarred surface helps them estimate what happened on our own planet, they said, because the craters provide an “absolute impactor flux” separate from any models that talk about how the Earth came together. Recall that erosion on the moon is very slow, providing accessible records of things that happened millions or billions of years ago.
But once the stuff is extracted, who does it belong to? A bill being considered by the U.S. House of Representatives says it would belong to “the property of the entity that obtained such resources.”
In a blog on Space Politics, aerospace analyst Jeff Foust outlined a discussion on the bill at the NewSpace 2014 conference last week. There are still a few wrinkles to be worked out, with one of the most pressing being to define what the definition of an asteroid is. Also, the backers of the bill are talking with the U.S. State Department to see if it would conflict with any international treaty obligations. (Here’s a copy of the bill on the Space Politics website.)
A single radar image frame close-up view of 2014 HQ124. Credit: NASA
The panel also noticed there is precedent for keeping and even selling samples: the visits to the Moon. Both Apollo astronauts (with the United States) and the Luna robotic missions (from the Soviet Union) returned samples of the Moon to the Earth. Some of the Apollo rocks, for example, are on display in museums. Others are stored in the NASA Lunar Sample Laboratory Facility at the Johnson Space Center in Houston.
That said, extraterrestrial property rights are difficult to define. For example, the United Nations Moon Treaty (more properly known as Agreement Governing the Activities of States on the Moon and Other Celestial Bodies) allows samples to be removed and stored for “scientific purposes”, and during these investigations they may “also use mineral and other substances of the moon in quantities appropriate for the support of their missions.” But it also adds that “the moon and its natural resources are the common heritage of mankind.”
Comet 67P/C-G photographed on July 14, 2014 from a distance of approximately 12 000 km.
Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
I thought the photos earlier this week were amazing. This little movie, made of 36 ‘smoothed’ or interpolated images of Comet 67P/Churyumov-Gerasimenko, takes it to the next level, showing the comet’s complex shape even more clearly as Rosetta nudges ever closer to its target. Some have likened it to a duck, a boot and even a baby’s foot. The original photos used for the animation were more pixelated, but a technique known as “sub-sampling by interpolation” was used to smooth out the pixels for a more natural look. Be aware that because of processing, 67P C-G appears smoother than it might be. While the surface looks textured, including what appears to be a small crater atop the duck’s head, we have to be careful at this stage not to over-interpret – some of the details are artifacts.
Raw pixelated image of the comet (left) and after smoothing. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
No one knows yet how such an unusual shape formed in the first place. Possibly the comet is a ‘contact binary’ made of two separate comets or two parts of larger, shattered comet that stuck together during a low-velocity collision. This may have happened more 4 billion years ago when the icy building blocks of the planets and comets were numerous and collisions far more frequent than they are today. Contact binaries aren’t uncommon; we see them in asteroids and comets alike.
* The comet may have once been a more spherical object but after many trips around the sun developed an asymmetrical shape from ice vaporization and outgassing.
* A near-catastrophic impact blasted away a huge chunk of comet ice.
* The strong gravitational pull experienced during a close pass of a large planet like Jupiter or Saturn may have pulled it into an irregular shape.
* A large outburst could have weakened a region on the comet’s surface that later crumbled away.
Detailed view of the likely contact binary asteroid 25143 Itokawa visited by the Japanese spacecraft Hayabusa in 2005. Credit: JAXA
“We will need to perform detailed analyses and modelling of the shape of the comet to determine how best we can fly around such a uniquely shaped body, taking into account flight control and astrodynamics, the science requirements of the mission, and the landing-related elements like landing site analysis and lander-to-orbiter visibility,” said Rosetta Mission Manager Fred Jansen. ” But with fewer than 10,000 km to go before the August 6th rendezvous, our open questions will soon be answered.”
In the meantime, keep the photos and movies coming. We can’t get enough.
Frame grab from a Youtube video of the brilliant meteor that flared over Australia overnight.
“It first looked like a plane with fire coming out of the tail.”— Aaron O.
“I have never seen anything like it. Big, bright and moving gently across sky – slower than a plane, not falling at all but moving across.” — Shannon H.
“Viewed from cockpit of aircraft at 37,000′. Was visible for two or three minutes.”— Landy T.
Flaming plane? Incandescent visitor from the asteroid belt? As the these comments from the AMS Fireball Log attest, the brilliant and s-l-o-w fireball that seared the sky over southeastern Australia tonight was probably one of the most spectacular displays of re-entering space junk witnessed in recent years.
Ted Molczan, citizen satellite tracker and frequent contributor to the amateur satellite watchers SeeSat-L site, notes that the timing and appearance almost certainly point to the decay or de-orbiting of the Russian Soyuz 2-1B rocket booster that launched the meteorological satellite Meteor M2 on July 8.
Meteor over New South Wales. Look closely near the end and you’ll see it disintegrate into small pieces.
The magnificent man-made meteor, weighing some 4,400 pounds (2,000 kg), was seen from Melbourne to Sydney across the states of Victoria and New South Wales around 10 p.m. Hundreds of people were stopped in their tracks. Most noticed how slowly the fireball traveled and how long it continue to burn on the way down.
Spacecraft that reenter from either orbital decay or controlled entry usually break up at altitudes between 45-52 miles (84-72 km) traveling around 17,500 mph (28,000 km/hour) . Compression and friction from the ever-thickening air cause the craft, or in this case, the rocket booster, to slow down and heat up to flaming incandescence just like a hunk of space rock arriving from the asteroid belt. In both cases, we see a brilliant meteor, however manmade debris.
A Delta 2 third stage, known as a PAM-D, reentered the atmosphere over the Middle East on Jan. 21, 2001. The titanium motor casing, weighing about 154 lbs. (70 kg), landed in Saudi Arabia about 150 miles from the capital of Riyadh. Credit: NASA, Orbital Debris Program Office
Occasional meteoroids break apart in the atmosphere and scatter meteorites just as pieces of occasional satellites, especially large, heavy craft, can survive the plunge and land intact – if a tad toasted. Whether anything remains of Russian rocket stage or where exactly it fell is still unknown. Here are a few more photos of successful space junk arrivals.
The only person to be hit by manmade space debris was Lottie Williams in 1997. She was unharmed. Credit: Tulsa World
Reportedly, only one person has been struck by satellite debris. In 1997 Lottie Williams of Tulsa, Oklahoma was hit on the shoulder while walking by a small, twisted piece of metal weighing as much as a crushed soda can. It was traced back to the tank of a Delta II rocket that launched a satellite in 1996. I suppose it’s only a matter of time before someone else gets hit, but the odds aren’t great. More likely, you’ll see what alarmed and delighted so many southeastern Australians Thursday night: a grand show of disintegration.
The asteroid Vesta as seen by the Dawn spacecraft. Credit: NASA/JPL-Caltech/UCAL/MPS/DLR/IDA
While “dark materials” may leave some of us thinking about a certain Philip Pullman book series, on the asteroid Vesta its presence belies something equally exotic: old smaller asteroid impacts on its surface.
The dark stuff on the lighter surface has puzzled researchers since it was discovered in 2011 (and has been brought up in other studies), but a new team says it has found that serpentine is among the components. Because that mineral can’t survive temperatures that are more than 400 degrees Celsius (752 degrees Fahrenheit), this means that scenarios such as volcanic eruptions can’t have caused it. This leaves only smaller asteroids, the team says.
“These meteorites are regarded as fragments of carbon-rich asteroids. The impacts must have been comparatively slow, because an asteroid crashing at high speeds would have produced temperatures too high to sustain serpentine,” the Max Planck Institute for Solar System Research stated.
Image of the crater Numisia on Vesta, where researchers found the spectral signature of serpentine. Picture taken by NASA’s Dawn spacecraft. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
“In a previous study, scientists from the MPS had calculated how dark material would be distributed on Vesta as a result of a low-speed oblique impact. Their results are consistent with the distribution of dark material on the edge of one of the two large impact basins in the southern hemisphere.”
The results came from analyzing images the NASA Dawn spacecraft took of Vesta between July 2011 and September 2012. The researchers recalibrated the data and also backed up their results by examining serpentine in laboratory conditions.
Amateur astronomer and physics teacher Asko Aikkila managed to catch the Kola fireball on videotape in Kuusamo, Finland on April 19, 2014. The picture has been processed to enhance the details. Credit: Asko Aikkila / Finnish Fireball Network
A spectacular fireball that crackled across the sky near the Russia-Finnish border on April 19th this year left more than a bright flash. A team of meteor researchers from Finland, Russia and the Czech Republic scoured the predicted impact zone and recently discovered extraterrestrial booty.
A 120 gram fragment (left) of the Annama meteorite found on May 29, 2014. Streamlines of molten material heated during atmospheric entry can be seen on the crust. At right, a 48g fragment found on the following day. Credit: Jakub Haloda (left) and Grigory Yakovlev
There’s a lot of excitement about the fall because it’s the first time a meteorite was found based on coordinated all-sky camera network observations by the Ursa Finnish Fireball Network. Esko Lyytinen of the network with help from Jarmo Moilanen and Steinar Midtskogen reconstructed the meteoroid’s trajectory and dark flight (when it’s no longer luminous but yet to strike the ground) using simulations based on photos, videos and eyewitness reports.
Kola fireball meteors fell near the Russian-Norwegian border. The fireball trajectory was modeled byEsko Lyytinen of the Ursa Finnish Fireball Network. Credit: Kuva Mikko Suominen / Celestia with info boxes translated by the author
The initial mass of meteoroid is estimated at about 1,100 pounds (500 kg). Much of that broke apart in the atmosphere and fell harmlessly as smaller stones. An international team of scientists mounted a 5-day expedition in late May after snow melt and before green up to uncover potential space rocks in the strewnfield, the name given to the oval-shaped zone where surviving fragments pepper the ground.
Russian amateur astronomer Nikolai Kruglikov discovered the first meteorite fragment in the middle of a dirt road. Credit: Tomas Kohout
On May 29, 2014, first 120 gram (4.2 ounce) meteorite fragment was found by Nikolai Kruglikov of Russia’s Ural Federal University on a forest road within the predicted impact area. The crew had been searching 1o hours a day when Kruglikov stopped the car to check out a suspect rock:
“Suddenly he started dancing and yelling. At first I could hardly believe it was a true discovery, but then I checked the composition of the rock using my instrument”, said Tomas Kohout, University of Helsinki physicist who participated in the hunt. The fusion-crusted stone displayed classic flow features from melting rock during high-speed atmospheric entry.
The very next day a second 48 gram crusted meteorite popped up. More are undoubtedly out there but the heavy brush numerous lakes make the finding challenging.
The crew is calling the new arrival the ‘Annama meteorite’ as it fell near the Annama River in Russia about 62 miles west of Murmansk. The Czech Geological Survey examined the space rocks and determined them to be ordinary chondrites representing the outer crust of an asteroid that got busted to bits in a long-ago collision. More than 95% of stony meteorites fall into this category including the 2013 fireball of Chelyabinsk, Russia.
Dashcam video of the brilliant fireball that dropped the ‘Annama meteorites’
“The Kola fireball is a rarity – it is one of only 22 cases where it was possible to determine its pre-impact solar system orbit before the impact with Earth’s atmosphere,” says Maria Gritsevich of the Finnish Geodetic Institute. “Knowing where the meteorite originates will help us better understand the formation and evolution of the solar system.” Congratulations Ursa!
