Actually it’s more like 3.5 times their weight in gold, according to today’s market value… and meteorite experts from SETI and NASA’s Marshall Space Flight Center.
During the daylight hours of April 22, 2012, reports came in from all over the north central California area of an extremely bright fireball — described as a “glittering sparkler” — and accompanying loud explosion. It was soon determined that this was the result of a meteoroid about the size of a minivan entering the atmosphere and disintegrating. It was later estimated that the object weighed about 70 metric tons and detonated with a 5-kiloton force.
Over a thousand meteorite hunters scrambled to the area, searching for any traces of the cosmic visitor’s remains. After a few days, several pieces of the meteorite were found and reported by five individuals, adding up to 46 grams in total.
Those pieces could be worth over $9,000 USD, according to Bill Cooke of NASA’s Meteoroid Environment Office at Marshall Space Flight Center.
Based on today’s market, that’s about 3.6 times the value of gold (about $1,660 per troy ounce — 31.1 grams).
The high value is due to the extreme rarity of the meteorite fragments. The California fireball is now known to have been created by a CM chondrite, a type of carbonaceous meteorite with material characteristics similar to comets.
SETI Institute's Franck Marchis and the chondrite fragments (F. Marchis)
According to Franck Marchis, Planetary Astronomer at the Carl Sagan Center of the SETI Institute and one of the coordinators of the meteorite reporting teams, CM chondrites appear to have been altered by water, and have deuterium-to-hydrogen ratios in line with what’s been measured in the tails of comets Halley and Hyakutake.
They also have been found to contain organic compounds and amino acids, lending to the hypothesis that such meteorites may have helped supply early Earth with the building blocks for life.
But due to their fragile composition, they are also incredibly rare. Only 1% of known meteorites are CM chondrites, making even the small handful of fragments found in California very valuable.
“This will be only the third observed CM fall in the US, after Crescent, OK, in 1936, (78 g) and Murray, KY, in 1950 (13 kg),” Marchis told Universe Today.
As far as what the finders will do with the fragments, that’s entirely up to them.
“They can sell them on eBay or they can lend them to the scientists… or make a donation.” Marchis said.
Just goes to show that all that glitters really isn’t gold — it could be even better.
Read more in an article by Sara Reardon on New Scientist, and read more on the comet/chondrite connection here. And the ongoing search for pieces of what’s now being referred to as the “Sutter’s Mill Meteorite” can be followed here and here.
The largest CM chondrite ever recovered was from a fall in Murchison, Australia on September 28, 1969. The total mass of its collected fragments weighed in at over 100 kg (220 lbs).
Remember that newly-discovered comet we mentioned a couple of days ago? Well, it’s gone. Poof. Into the Sun and never to return, it was a sungrazer’s final voyage.
The video above features images from the SOHO spacecraft and description from Bad Astronomer Phil Plait, with music by Kevin MacLeod.
Alas, poor SWAN… at least we knew him.
Read more about the history of Comet SWAN on the Sungrazing Comets site. Video credit: NASA/SOHO (and thanks to Phil Plait for the assembly.)
A new comet has been discovered by the SOHO team, and it — like Lovejoy before it, almost three months to the day — is headed directly toward the Sun. Discovered by SOHO’s SWAN instrument, the comet has been dubbed Comet SWAN… making this a real swan dive (or, perhaps more appropriately, its swan song.)
The animation above has a lot of random noise in it from recent solar outbursts… can you spot the comet? If not, read on…
Labeled frame of the LASCO image (courtesy of SpaceWeather.com)
There’s Comet SWAN, just above the darker silhouette of the bar that holds the shielding disk over the center of the imager (which blocks the glare from the Sun itself.)
The comet is likely another member of the Kreutz family of comets, an extended family of pieces that broke off a larger comet several hundred years ago (which itself may have been a survivor of a breakup in 371 B.C.!) Comet Lovejoy was also a Kretuz sungrazer but it was considerably larger and brighter, which may have helped it survive its Dec. 15 solar close encounter to re-emerge on the opposite side, surprising astronomers everywhere!
It was just about three months ago that the astronomy world watched in awe as the recently-discovered comet Lovejoy plummeted toward the Sun on what was expected to be its final voyage, only to reappear on the other side seemingly unscathed! Surviving its solar visit, Lovejoy headed back out into the solar system, displaying a brand-new tail for skywatchers in southern parts of the world (and for a few select viewers above the world as well.)
How did a loosely-packed ball of ice and rock manage to withstand such a close pass through the Sun’s blazing corona, when all expectations were that it would disintegrate and fizzle away? A few researchers from Germany have an idea.
Scientists from the Max Planck Institute for Extraterrestrial Physics and the Braunschweig University of Technology have hypothesized that Comet Lovejoy managed to hold itself together through the very process that, to most people, defines a comet: the outgassing of sublimated icy material.
As a comet near the Sun, the increased heating from solar radiation causes the frozen materials within the nucleus to sublimate — go directly and suddenly from solid to gas, skipping the liquid middle stage — and, in doing so, burst through the surface of the comet and create the long, hazy reflective tail that is so often associated with them.
Overview of the forces acting on sungrazing comets. (Illustration from paper.)
In the case of Lovejoy, which was on a direct path toward the Sun, the sublimation itself may have provided enough outward force across its surface to literally keep it together, according to the team’s research.
“The reaction force caused by the strong outgassing (sublimation) of the nucleus near the Sun acts to keep the nucleus together and to overcome the tidal disruption,” the paper claims.
In addition, the team states that the size of the comet’s nucleus can be derived using an equation that takes into consideration the combined forces of outgassing, the material composition of the comet’s nucleus, the comet’s own gravity and the tidal forces exerted by the comet’s close proximity to the Sun (i.e., the Roche limit).
Using that equation, the team concluded that the diameter of Comet Lovejoy’s nucleus is anywhere between 0.2 km and 11 km (.125 miles and 6.8 miles). Any smaller and it would have lost too much material during its pass (and had too little gravity); any larger and it would have been too thick for outgassing to provide enough counterbalancing force.
If this hypothesis is correct, taking a trip around the Sun may not mean the end for all comets… at least not those of a certain size!
Watch the video of Lovejoy’s Dec. 15 solar swing below:
The paper was submitted to the journal Icarus on March 8, 2012 by Bastian Gundlach. See the full text here.
Exotic sediments found beneath the floor of Lake Cuitzeo in central Mexico support theories of a major cosmic impact event 12,900 years ago, report a 16-member international research team. The impact may have caused widespread environmental changes and contributed to the extinctions of many large animal species.
Images of single and twinned nanodiamonds show the atomic lattice framework of the nanodiamonds. Each dot represents a single atom. (Source: UCSB release.)
The team found a 13,000-year-old layer of sediment that contains materials associated with impact events, such as soot, impact spherules and atomic-scale structures known as nanodiamonds. The nanodiamonds found at Lake Cuitzeo are of a variety known as lonsdaleite, even harder than “regular” diamond and only found naturally as the result of impact events.
The thin layer of sediment below Cuitzeo corresponds to layers of similar age found throughout North America, Greenland and Western Europe.
It’s thought that a large several-hundred-meter-wide asteroid or comet entered Earth’s atmosphere at a shallow angle 12,900 years ago, melting rocks, burning biomass and, in general, causing widespread chaos and destruction. This hypothesized event would have occurred just before a period of unusually cold climate known as the Younger Dryas.
The Younger Dryas has been associated with the extinction of large North American animals such as mammoths, saber-tooth cats and dire wolves.
“The timing of the impact event coincided with the most extraordinary biotic and environmental changes over Mexico and Central America during the last approximately 20,000 years, as recorded by others in several regional lake deposits,” said James Kennett, professor of earth science at UC Santa Barbara and member of the research team. “These changes were large, abrupt, and unprecedented, and had been recorded and identified by earlier investigators as a ‘time of crisis.’ ”
The exotic materials found in the sediment beneath Cuitzeo could not have been created by any volcanic, terrestrial or man-made process. “These materials form only through cosmic impact,” Kennett said.
The only other widespread sedimentary layer ever found to contain such an abundance of nanodiamonds and soot is found at the K-T boundary, 65 million years ago. This, of course, corresponds to the impact event that led to the extinction of the dinosaurs.
The researchers’ findings appeared March 5 in the Proceedings of the National Academy of Sciences. Read the news release from UC Santa Barbara here.
“Friday, February 10th 2012 just felt like the perfect night for a comet to be discovered by an amateur astronomer,” writes Fred Bruenjes on his astronomy blog. And, this past Friday night, that’s exactly what Fred did.
Here’s how he did it:
Using custom-written software to operate a 14″ Meade LX200GPS telescope in his self-built observatory in Warrensburg, Missouri, Fred set his system up to capture images of the sky on that cold evening, not allowing himself to be chased inside by the low temperatures or the bright, rising moon. After some technical difficulties with his dSLR, Fred managed to acquire some quality images. While making a cursory look through the blink data, Fred was surprised to spot a faint burry object visible moving across three frames. A check of online databases of known objects brought up no positive hits — this was something that hadn’t been seen before.
Raw-color discovery image. (Fred Bruenjes)
Fred describes the “eureka” moment on his blog:
A check of known objects in the region had a lot of results in the area, but all were moving eastward while my fuzzy was moving westward. Rocks don’t make U-turns. This was really getting exciting. I had Jen, my better half, an accomplished astro imager, take a look at the images and before I could point out the faint smudge she exclaimed “That’s a comet!”
Still, Fred notes, “it wasn’t a slam-dunk.” The images were faint and there could have been other causes of blurry spots in digital images. But a check of the raw color data revealed a greenish coloration to the object’s glow, which is indicative of cyanogen and carbon emission — typical hallmarks of comets. “Very encouraging,” Fred added.
Another night’s observation was needed. If it was a comet, it would appear again along its expected trajectory. Of course, with an unidentified comet there would be no known orbit, so Fred had to manually extrapolate its position. When he trained his telescope onto his calculated coordinates the following evening and began taking images, there it was… the same faint, fuzzy green blur from the previous night, slowly appearing in the darkening sky right where it should be.
“Oh. Wow. It was dead nuts at where it was supposed to be,” Fred writes. “Wow. This thing is for real! It’s at about this time that it begins to sink in that a lifelong quest has just been fulfilled. I just crossed another thing off the bucket list!”
Fred spent the next hour gathering images to send in to the IAU’s Minor Planet Center, in the hopes of having the object cataloged so that others could locate and observe it. He didn’t have to wait long; within five minutes the object was listed on the Near-Earth Object Confirmation Page, and dubbed C/2012 C2 (Bruenjes), in honor of its discoverer.
Now that’s just got to feel good.
Comet Bruenjes is an NEO currently about 0.555 AU away from Earth. Its exact size and orbital period isn’t known, and it may even be a returning comet or piece from a larger one… the official report isn’t out yet. It appears to have a fairly inclined orbit relative to the ecliptic, based on the current diagram created by JPL’s Small-Body Database.
Currently plotted orbit of C/2012 C2 (Bruenjes) (NASA/JPL)
The comet’s total magnitude is 16.6, so it is dim and not visible to the naked eye. Fred told Universe Today in an email: “it’s in the constellation Aries, about six degrees north of Jupiter. Just after sunset in the Northern hemisphere it’s high in the southwest, nearly overhead.”
Stay tuned for more updated information on this newly-discovered member of our solar system. And congratulations to Fred Bruenjes, comet-hunter extraordinaire!
Yes, it’s coming. Yes, it’s big. Yes, it will be even closer than the Moon. And yes… we’re completely safe.
The 400-meter-wide asteroid 2005 YU55 is currently zipping through the inner Solar System at over 13 km (8 miles) a second. On Tuesday, November 8, at 6:28 p.m. EST, it will pass Earth, coming within 325,000 km (202,000 miles). This is indeed within the Moon’s orbit (although YU55’s trajectory puts it a bit above the exact plane of the Earth-Moon alignment.) Still, it is the closest pass by such a large object since 1976… yet, NASA scientists aren’t concerned. Why?
Because its orbit has been well studied, there’s nothing in its way, and frankly there’s simply nothing it will do to affect Earth.
Animation of 2005 YU55's trajectory on Nov. 8. (NASA/JPL) Click to play.
Period.
2005 YU55’s miniscule gravity will not cause earthquakes. It has no magnetic field. It will not strike another object, or the Moon, or the Earth. It will not come into contact with cometary debris, Elenin, a black dwarf, Planet X, or Nibiru. (Not that those last three even exist.) No, YU55 will do exactly what it’s doing right now: passing through the Solar System. It will come, it will go, and hopefully NASA scientists – as well as many amateur astronomers worldwide – will have a chance to get a good look at it as it passes.
Scientists with NASA’s Near-Earth Objects Observation Program will begin tracking YU55 on Friday, November 4 using the 70-meter radar telescope at the Deep Space Network in Goldstone, California , as well as with the Arecibo Planetary Radar Facility in Puerto Rico beginning November 8. These facilities will continue to track it until the 10th.
This close pass will offer a great opportunity to get detailed radar imaging of YU55, an ancient C-type asteroid literally darker than coal. Since these objects can be difficult to observe using visible light, radar mapping can better reveal details about their surface and composition.
To help inform the public about YU55 NASA’s Jet Propulsion Laboratory in Pasadena recently hosted a live Q&A session on Ustream featuring specialists Marina Brozovic, a Goldstone Radar Team scientist, and Don Yeomans, manager of NASA’s Near-Earth Object Program. They fielded questions sent in via chat and Twitter… a recording of the event in its entirety can be seen below:
Undoubtedly there will still be those who continue to spread misinformation about 2005 YU55. After all, they did the same with the now-disintegrated comet Elenin. But the truth is out there… and the truth is that there’s no danger, no cover-ups, no “plots”, and simply no cause for concern.
UPDATE: JPL has released a brief video about YU55 featuring research scientist Lance Benner, who specializes in radar imaging of near-Earth objects:
Although classified as a potentially hazardous object, 2005 YU55 poses no threat of an Earth collision over at least the next 100 years. However, this will be the closest approach to date by an object this large that we know about in advance and an event of this type will not happen again until 2028 when asteroid (153814) 2001 WN5 will pass to within 0.6 lunar distances. – Near-Earth Object Program, JPL
Based on an observation posted on the Near Earth Object confirmation page from an image taken by A. D. Grauer using the mount Lemmon observatory, Faulkes telescope team members Nick Howes, Giovanni Sostero and Ernesto Guido along with University of Glamorgan student Antos Kasprzyk and amateur astronomer Iain Melville, imaged what is potentially some of the first direct evidence for a Trojan Jupiter Comet
Comet P/2010 TO20 (LINEAR-GRAUER) was immediately recognised by the team from looking at the orbit to be a highly unusual object, but it was only when the images came through from the faulkes observations that the true nature of the object became clear
The observations showed a distinct cometary appearance, with a sharp central condensation, compact coma and a wide, fan-shaped tail.
This is no ordinary comet, and supports the theory and initial spectral observation work by a team using the keck telescope in Hawaii. Closer analysis of their object (part of a binary known as the Patroclus pair) showed that it was made of water ice and a thin layer of dust, but at the time of writing, no direct images of a Jupiter Trojan showing evidence of a coma and tail had been taken.
The Faulkes teams above image, combined with the original observations by Grauer clearly show a cometary object, thus confirming the Keck team’s hypothesis.
According to the CBET released today “After two nights of observations of Grauer’s comet had been received at the Minor Planet Center.
Spahr realized that this object was identical with an object discovered a year ago by the LINEAR project (discovery observation tabulated below; cf. MPS 351583) that appeared to be a Jupiter Trojan minor planet.”
The observations have now proved it is not a minor planet, but a comet.
This discovery could provide new clues about the evolution of the Solar System, suggesting that the Gas Giants formed closer to the Sun and as they moved further away, they caused massive perturbations with Kuiper Belt objects, trapping some in their own orbits.
Nick Howes on the Faulkes team said “When we first saw the preliminary orbit, we knew it was a quite remarkable object” Howes also added “To have a University Student also involved is terrific for the degree program at Glamorgan and also for the Faulkes project. We’d like to extend our congratulations to Al Grauer” for his detection of this groundbreaking new comet” and we’re immensely proud to be part of the CBET released by the IAU confirming its nature
Comet Elenin, the supposed “doomsday comet” that has inspired so much confusion and controversy since its discovery in December 2010, may have broken apart completely during its recent pass around the Sun.
Discoverer Leonid Elenin posted the image above earlier today on his website, SpaceObs.org. Taken with the International Scientific Optical Network’s 18″ telescope in New Mexico (ISON-NM), it shows what may be the remnants of Elenin, a faint cloud barely visible after its exit from behind the Sun.
“On the left you can see possible position of this ‘cloud’,” Leonid writes. “Brightness of this object does not exceed 18m, which means what now, magnitude of the comet is lower then predicted on 12m. Hopefully in the near future debris of the comet will be observed on a large telescopes, and perhaps we’ll see some details of this ‘cloud’.”
Ground-based viewing of Elenin’s remains may be hampered over the next few days by the full Moon, he adds.
Although many rumors have been spread about the catastrophic danger Elenin poses to humans, in reality the comet was never a threat. Not expected to come any closer than 22 million miles (35 million km) to Earth, it’s been previously speculated that Elenin would most likely disintegrate during its current orbit.
“I don’t know why fearmongers [chose] my comet,” Leonid Elenin told Universe Today. “I received many letters from scared people. But if they believe in conspiracy theories I can’t help them.”
Hopefully this helps put some of the doomsday nonsense to rest!
It starts out innocently enough: a small speck against a field of background stars, barely noticeable in the image data. But… it’s a speck that wasn’t there before. Subsequent images confirm its existence – there’s something out there. Something bright, something large, and it’s moving through our solar system very quickly. The faint blur indicates that it’s a comet, an icy visitor from the outermost reaches of the solar system. And it’s headed straight toward Earth.
Exhaustive calculations are run and re-run. Computer simulations are executed. All possibilities are taken into consideration, and yet there’s no alternative to be found; our world will face a close encounter with a comet in mere months’ time. Phone calls are made, a flurry of electronic messages fly between computer terminals across the world, consultations are held with top experts in the field. We are unprepared… what can we do? What does this mean for civilization as we know it? What will this speeding icy bullet from outer space do to our planet?
The answer? Nothing.
Nothing at all. In fact, it probably won’t even be very interesting to look at – if you can even find it when it passes by.
(Sorry for the let-down.)
There’s been a lot of buzz in the past several months regarding Comet Elenin, a.k.a. C/2010 X1, which was discovered by Russian astronomer Leonid Elenin on December 10, 2010. Elenin spotted the comet using a telescope in New Mexico remotely from his location in Lyubertsy, Russia. At that time it was about 647 million kilometers (401 million miles) from Earth… in the time since it has closed the distance considerably, and is now around 270 million km away. Elenin is a long-period comet, which means it has a rather large orbit around the Sun… it comes in from a vast distance, swings around the Sun and heads back out to the depths of the solar system – a round trip lasting over 10,000 years. During its current trip it will pass by Earth on October 16, coming as close as 35 million km (22 million miles).
Elenin's orbit via the JPL Small-Body Database Browser
Yes, 22 million miles.
That’s pretty far.
Way too far for us to be affected by anything a comet has to offer. Especially a not-particularly-large comet like Elenin.
Some of the doomy-gloomy internet sites have been mentioning the size of Elenin as being 80,000 km across. This is a scary, exaggerated number that may be referring to the size of Elenin’s coma – a hazy cloud of icy particles that surrounds a much, much smaller nucleus. The coma can be extensive but is insubstantial; it’s akin to icy cigarette smoke. Less than that, in fact… a comet’s coma and tail are even more of a vacuum than can be reproduced in a lab on Earth! In reality most comets have a nucleus smaller than 10km…that’s less than a billionth the mass of Earth (and a far cry from 80,000 km.) We have no reason to think that Elenin is any larger than this – it’s most likely smaller.
Ok, but how about the gravitational and/or magnetic effect of a comet passing by Earth? That’s surely got to do something, right? To Earth’s crust, or the tides? For the answer to that, I will refer to Don Yeomans, a researcher at NASA’s Near-Earth Object Program Office at JPL:
“Comet Elenin will not only be far away, it is also on the small side for comets. And comets are not the most densely-packed objects out there. They usually have the density of something akin to loosely packed icy dirt,” said Yeomans. “So you’ve got a modest-sized icy dirtball that is getting no closer than 35 million kilometers. It will have an immeasurably miniscule influence on our planet. By comparison, my subcompact automobile exerts a greater influence on the ocean’s tides than comet Elenin ever will.”
“It will have an immeasurably miniscule influence on our planet. By comparison, my subcompact automobile exerts a greater influence on the ocean’s tides than comet Elenin ever will.”
– Don Yeomans, NASA / JPL
And as far as the effect from Elenin’s magnetic field goes… well, there is no effect. Elenin, like all comets, doesn’t have a magnetic field. Not much else to say there.
But the claims surrounding Elenin have gone much further toward the absurd. That it’s going to encounter another object and change course to one that will cause it to impact Earth, or that it’s not a comet at all but actually a planet – Nibiru, perhaps? – and is on a collision course with our own. Or (and I particularly like this one) that alien spaceships are trailing Elenin in such a way as to remain undetected until it’s too late and then they’ll take over Earth, stealing our water and natural resources and turning us all into slaves and/or space munchies… or however the stories go. (Of course the government and NASA and Al Gore and Al Gore’s hamster are all in cahoots and are withholding this information from the rest of us. That’s a given.) These stories are all just that – stories – and have not a shred of science to them, other than a heaping dose of science fiction.
“We live in nervous times, and conspiracy theories and predictions of disaster are more popular than ever. I like to use the word cosmophobia for this growing fear of astronomical objects and phenomena, which periodically runs amuck on the Internet. Ironically, in pre-scientific times, comets were often thought to be harbingers of disaster, mostly because they seemed to arrive unpredictably – unlike the movements of the planets and stars, which could be tracked on a daily and yearly basis.”
– David Morrison, planetary astronomer and senior scientist at NASA’s Ames Research Center
The bottom line is this: Comet C/2010 X1 Elenin is coming, and it will pass by Earth at an extremely safe distance – 100 times the distance from Earth to the Moon. It will not be changing direction between now and then, it will not exert any gravitational effect on Earth, its magnetic field is nonexistent and there are no Star Destroyers cruising in its wake. The biggest effect it will have on Earth is what we are able to learn about it as it passes – after all, it is a visitor from the far reaches of our solar system and we won’t be seeing it again for a very, very long time.
I’m sure we’ll have found something else to be worried about long before then.
“This intrepid little traveler will offer astronomers a chance to study a relatively young comet that came here from well beyond our solar system’s planetary region. After a short while, it will be headed back out again, and we will not see or hear from Elenin for thousands of years. That’s pretty cool.”
– Don Yeomans
For more information about Elenin, check out this JPL news release featuring Don Yeomans, and there’s a special public issue of Astronomy Beat, a newsletter from the Astronomical Society of the Pacific, that features David Morrison of NASA’s Ames Research Center discussing many of the misconceptions about Elenin.
An updated chart of Elenin’s orbit and statistics can be viewed here.
