[meteorite-list] Rocks from Space Picture of the Day - January 25, 2008
http://www.rocksfromspace.org/January_25_2008.html _ **Biggest Grammy Award surprises of all time on AOL Music. (http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp00300025 48) __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] NASA Scientists Get First Images of Asteroid 2007 TU24
http://www.jpl.nasa.gov/news/news.cfm?release=2008-014 NASA Scientists Get First Images of Earth Flyby Asteroid Jet Propulsion Laboratory January 25, 2008 Scientists at NASA's Jet Propulsion Laboratory in Pasadena, Calif., have obtained the first images of asteroid 2007 TU24 using high-resolution radar data. The data indicate the asteroid is somewhat asymmetrical in shape, with a diameter roughly 250 meters (800 feet) in size. Asteroid 2007 TU24 will pass within 1.4 lunar distances, or 538,000 kilometers (334,000 miles), of Earth on Jan. 29 at 12:33 a.m. Pacific time (3:33 a.m. Eastern time). With these first radar observations finished, we can guarantee that next week's 1.4-lunar-distance approach is the closest until at least the end of the next century, said Steve Ostro, JPL astronomer and principal investigator for the project. It is also the asteroid's closest Earth approach for more than 2,000 years. Scientists at NASA's Near-Earth Object Program Office at JPL have determined that there is no possibility of an impact with Earth in the foreseeable future. Asteroid 2007 TU24 was discovered by the NASA-sponsored Catalina Sky Survey on Oct. 11, 2007. The first radar detection of the asteroid was acquired on Jan. 23 using the Goldstone 70-meter (230-foot) antenna. The Goldstone antenna is part of NASA's Deep Space Network Goldstone station in Southern California's Mojave Desert. Goldstone's 70-meter diameter (230-foot) antenna is capable of tracking a spacecraft traveling more than 16 billion kilometers (10 billion miles) from Earth. The surface of the 70-meter reflector must remain accurate within a fraction of the signal wavelength, meaning that the precision across the 3,850-square-meter (41,400-square-foot) surface is maintained within one centimeter (0.4 inch). Ostro and his team plan further radar observations of asteroid 2007 TU24 using the National Science Foundation's Arecibo Observatory in Puerto Rico on Jan. 27-28 and Feb. 1-4. The asteroid will reach an approximate apparent magnitude 10.3 on Jan. 29-30 before quickly becoming fainter as it moves farther from Earth. On that night, the asteroid will be observable in dark and clear skies through amateur telescopes with apertures of at least 7.6 centimeters (three inches). An object with a magnitude of 10.3 is about 50 times fainter than an object just visible to the naked eye in a clear, dark sky. Scientists working with Ostro on the project include Lance Benner and Jon Giorgini of JPL, Mike Nolan of the Arecibo Observatory, and Greg Black of the University of Virginia. NASA detects and tracks asteroids and comets passing close to Earth. The Near Earth Object Observation Program, commonly called Spaceguard, discovers, characterizes and computes trajectories for these objects to determine if any could be potentially hazardous to our planet. The Arecibo Observatory is part of the National Astronomy and Ionosphere Center, a national research center operated by Cornell University, Ithaca, N.Y., for the National Science Foundation. JPL is a division of the California Institute of Technology in Pasadena. For more information, visit http://neo.jpl.nasa.gov Media contact: Contact: DC Agle 818-393-9011 Jet Propulsion Laboratory, Pasadena, Calif. [EMAIL PROTECTED] Grey Hautaluoma 202-358-0668 Headquarters, Washington [EMAIL PROTECTED] 2008-014 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Calendar update
http://www.rocksfromspace.org/January_2008.html Sincerely, Michael Johnson http://www.spacerocksinc.com http://www.sikhote-alin.org http://www.rocksfromspace.org __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Asteroid 2007 TU24 to Make Rare Close Flybyof Earth January 29
For those of us living under dark skies, Comet Holmes is far from gone. It remains an easy and obvious naked eye object, of remarkable size. In binoculars, it's even more impressive. As for TU24, at something like 3 arcsec/sec, no patience will be required to see it move. That's fast enough that you'll actually see it drifting against background stars. It will be closest on the morning of 29 January UT. So from North America, look for it in Perseus on the evening of 28/29 January. By 7pm EST on 29 January, it will be in Ursa Major, and a day past its closest approach, although it may still be getting brighter. Chris * Chris L Peterson Cloudbait Observatory http://www.cloudbait.com - Original Message - From: Jerry [EMAIL PROTECTED] To: Ron Baalke [EMAIL PROTECTED]; Meteorite Mailing List meteorite-list@meteoritecentral.com Sent: Friday, January 25, 2008 8:36 PM Subject: Re: [meteorite-list] Asteroid 2007 TU24 to Make Rare Close Flybyof Earth January 29 Looks like Perseus will be the center of attention once again. With Comet Holmes all but gone, Asteroid 2007 TU24 will glide through Perseus on the evening of Jan 29 between 7pm and midnight EST. For those of us lucky enough to have no cloud cover, a late rising moon will not interfere with viewing. It appears to be moving swiftly enough at that time to be distinguishable from background stars if one is patient enough to spend an hour+ studying a telescopic [or good binocular] image. My own long range weather forecast is not promising Jerry Flaherty __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Rocks from Space Picture of the Day - January 26, 2008
http://www.rocksfromspace.org/January_26_2008.html __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Asteroid 2007 TU24 to Make Rare Close Flyby of Earth January 29
Looks like Perseus will be the center of attention once again. With Comet Holmes all but gone, Asteroid 2007 TU24 will glide through Perseus on the evening of Jan 29 between 7pm and midnight EST. For those of us lucky enough to have no cloud cover, a late rising moon will not interfere with viewing. It appears to be moving swiftly enough at that time to be distinguishable from background stars if one is patient enough to spend an hour+ studying a telescopic [or good binocular] image. My own long range weather forecast is not promising Jerry Flaherty - Original Message - From: Ron Baalke [EMAIL PROTECTED] To: Meteorite Mailing List meteorite-list@meteoritecentral.com Sent: Friday, January 25, 2008 11:44 AM Subject: [meteorite-list] Asteroid 2007 TU24 to Make Rare Close Flyby of Earth January 29 http://www.jpl.nasa.gov/news/news.cfm?release=2008-012 Asteroid to Make Rare Close Flyby of Earth January 29 Jet Propulsion Laboratory January 24, 2008 Scientists are monitoring the orbit of asteroid 2007 TU24. The asteroid, believed to be between 150 meters (500 feet) and 610 meters (2,000 feet) in size, is expected to fly past Earth on Jan. 29, with its closest distance being about 537,500 kilometers (334,000 miles) at 12:33 a.m. Pacific time (3:33 a.m. Eastern time). It should be observable that night by amateur astronomers with modest-sized telescopes. Asteroid 2007 TU24 was discovered by the NASA-sponsored Catalina Sky Survey on Oct. 11, 2007. Scientists at NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif., have determined that there is no possibility of an impact with Earth in the foreseeable future. This will be the closest approach by a known asteroid of this size or larger until 2027, said Don Yeomans, manager of the Near Earth Object Program Office at JPL. As its closest approach is about one-and-a-half times the distance of Earth to the moon, there is no reason for concern. On the contrary, Mother Nature is providing us an excellent opportunity to perform scientific observations. Asteroid 2007 TU24 will reach an approximate apparent magnitude 10.3 on Jan. 29-30 before quickly becoming fainter as it moves farther from Earth. On that night, the asteroid will be observable in dark and clear skies through amateur telescopes with apertures of at least 7.6 centimeters (3 inches). An object with a magnitude of 10.3 is about 50 times fainter than an object just visible to the naked eye in a clear, dark sky. NASA detects and tracks asteroids and comets passing close to Earth. The Near Earth Object Observation Program, commonly called Spaceguard, discovers, characterizes and computes trajectories for these objects to determine if any could be potentially hazardous to our planet. For more information, visit http://neo.jpl.nasa.gov. DC Agle 818-393-9011 Jet Propulsion Laboratory, Pasadena, Calif. [EMAIL PROTECTED] Grey Hautaluoma 202-358-0668 Headquarters, Washington [EMAIL PROTECTED] 2008-012 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Enthusiasts of Martian Meteorites
Hallo Bernd and List-members, I still love this image of the Rocks From Space Picture of the Day December 16, 2007 http://www.rocksfromspace.org/December_16_2007.html I just never knew Bob was so religious! ;-) I am sure you will aquire one or maybe two of these beauties, maybe more! Great deals! Wouldn't they be awesome in a thin section? Guess there is a nice piece at Michael Blood's auction! http://michaelbloodmeteorites.com/TucsonAuction08.html Happy weekend every one! Stay dry Californians! With best regards, Moni To: Meteorite-list@meteoritecentral.com From: [EMAIL PROTECTED] Date: Fri, 25 Jan 2008 22:16:53 + Subject: [meteorite-list] Enthusiasts of Martian Meteorites Hello All, Since we all share this passion for meteorites, those messengers from our solar neighborhood, I would like to draw your attention to Bob Verish's offer of one of the most spectacular Martian meteorites in recent history! How many among us can really boast of owning a piece of either LA 001 or LA 002!?! Have a look and watch your saliva ;-) http://marzmeteorite.tripod.com/saw-cuttings/la-saw.htm Bernd _ Connect and share in new ways with Windows Live. http://www.windowslive.com/share.html?ocid=TXT_TAGHM_Wave2_sharelife_012008 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] New Georgia find back in the meteorite community
I went down to Statesboro last weekend and brought this back: http://www.fallingrocks.com/Collections/Statesboro.htm Nice to know it will stay in Georgia, and our MAG group (www.meteoriteassociationofgeorgia.org) is pretty excited about it. Georgia meteorites are special to kids in Georgia, as local falls and finds bring the subject a lot closer to home for them (as everyone knows from their own local experiences Im sure). Sending this out so those so inclined or intrigued can see better images than were previously submitted on the heels of the classification most especially Im looking forward to Harlan Trammells return from the Florida Keys to check out the stone that fell in the town of his alma mater! Dave __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] AD: Auctions Closing This Weekend.
Hi All, I've got some auctions closing this weekend with more Canyon Diablo, and Campo meteorites. One piece is especially nice. A monster 660gram Canyon Diablo for only .45/g http://search.ebay.com/_W0QQsassZfreel3orn Regards, Eric Wichman www.MeteoritesUSA.com __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Rocks from Heaven new email address
Hello List, I wanted to inform everyone that I have a new email address, so in the future please send emails to: [EMAIL PROTECTED] Thanks, Jason Phillips Rocks from Heaven www.rocksfromheaven.com telephone: 217-832-4505 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Arecibo Astronomers Prepare to Obtain Close Images of Asteroid 2007 TU24
http://www.eurekalert.org/pub_releases/2008-01/cuc-aap012508.php Public release date: 25-Jan-2008 Contact: Blaine Friedlander [EMAIL PROTECTED] 607-254-8093 Cornell University Communications Arecibo astronomers prepare to obtain close images of a near-Earth asteroid ITHACA, N.Y. - The Arecibo Observatory in Arecibo, Puerto Rico will observe a newly discovered asteroid on Jan. 27-28, as the object called 2007 TU24 passes within 1.4 lunar distances, or 334,000 miles, from Earth. The asteroid, estimated at between 150 and 600 meters in diameter - about 500 feet to 1,900 feet, or the size of a football field, at 360 feet, to the size of Chicago's 110-story Sears Tower, at 1,454 feet - was discovered by the University of Arizona's Catalina Sky Survey in October 2007. It poses no threat to Earth, but its near approach gives Arecibo astronomers a golden opportunity to learn more about potentially hazardous near-Earth objects. We don't yet know anything about this asteroid, said Mike Nolan, head of radar astronomy at the Puerto Rico observatory. Such objects pass near Earth with relative frequency, he said - approximately one every five years or so - but it's rare that astronomers have enough advance notice to plan for rigorous observing. Because it's coming so close, we'll get our highest quality imaging, said Nolan. Using Arecibo's powerful radar, which is the most sensitive in the world, researchers will gauge the object's size, observe its speed and measure its spin. Switching then to imaging mode, which will offer resolution to 7.5 meters - three times more precise than NASA's Goldstone telescope, the only other radar telescope in the world - the researchers hope to map the object's surface in detail. The Robert C. Byrd Green Bank Telescope, Green Bank, W.Va., will receive Arecibo's echo from the asteroid and transmit its data back to Arecibo. TU24 is one of an estimated 7,000 near-Earth objects, its size or larger - most have never been closely studied. We have good images of a couple dozen objects like this, and for about one in 10, we see something we've never seen before, said Nolan. We really haven't sampled the population enough to know what's out there. Arecibo's radar is vital for continuing to classify and understand such objects, said Cornell University assistant professor of astronomy Jean-Luc Margot. Arecibo does a fantastic job at getting images, discovering the shape, spin and reflection properties of such an object . . . all these things that are important to know.' The telescope will be trained on TU24 Jan. 27-28 and again Feb. 1-4. Goldstone's planetary radar observed it Jan. 23-24. ### Steven Ostro, astronomer at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., is principal investigator for the project; also contributing are Lance Benner and Jon Giorgini at JPL and Greg Black of the University of Virginia. Their research is funded by NASA. The Arecibo Observatory is part of the National Astronomy and Ionosphere Center, a national research center operated by Cornell for the National Science Foundation. The Green Bank Telescope is operated by National Radio Astronomy Observatory for the National Science Foundation. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Weston sizes
ks1u wrote: was wondering how many of you may have pieces over 4 grams? Hello George, I have a 6.30 g and a 3.85 g fragment of WESTON in my collection. Best regards, Peter __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] MESSENGER: Counting Mercury's Craters
http://messenger.jhuapl.edu/news_room/status_report_01_24_08.html MESSENGER Mission News January 24, 2008 Counting Mercury's Craters On January 14, 2008, MESSENGER flew by Mercury and snapped images of a large portion of the surface that had not been previously seen by spacecraft. Ever since the first images were received back on Earth one day later, January 15, MESSENGER team members have been closely examining and studying this new terrain with great interest and excitement. One of many investigations underway includes identifying and measuring the impact craters on these previously unseen regions. The density of craters on the surface of a planet can be used to indicate the relative age of different places on the surface; the more craters the surface has accumulated, the older the surface. By counting craters on different areas of Mercury's surface, a relative geologic history of the planet can be constructed, indicating which surfaces formed first and which formed later. However, this process is also time consuming; Mercury has a lot of craters! This image http://messenger.jhuapl.edu/gallery/sciencePhotos/image.php?gallery_id=2image_id=136 shows just a portion (276 kilometers, or 172 miles, wide) of one frame taken with the Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS). In this image alone, 763 craters have been identified and measured (shown in green) along with 189 hills (shown in yellow). Altogether, 491 frames were taken by the NAC to create high-resolution mosaics of Mercury's surface. Of course, simply counting the craters is not enough. Each crater has to be measured and classified to fully interpret the differences in crater density. Many small craters form as secondaries, as clumps of material ejected from a primary crater re-impact the surface in the regions surrounding the primary. In order to learn about the history of asteroid and comet impacts on Mercury, scientists have to distinguish between the primary and secondary craters. Once many more craters are measured, MESSENGER researchers will have new insights into the geological history of Mercury. Additional information and features from this first flyby will be available online at http://messenger.jhuapl.edu/mer_flyby1.html, so check back frequently. Following the flyby, be sure to check for the latest released images and science results! MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) is a NASA-sponsored scientific investigation of the planet Mercury and the first space mission designed to orbit the planet closest to the Sun. The MESSENGER spacecraft launched on August 3, 2004, and after flybys of Earth, Venus, and Mercury will start a yearlong study of its target planet in March 2011. Dr. Sean C. Solomon, of the Carnegie Institution of Washington, leads the mission as principal investigator. The Johns Hopkins University Applied Physics Laboratory built and operates the MESSENGER spacecraft and manages this Discovery -class mission for NASA. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] MRO HiRISE Images - January 24, 2008
MARS RECONNAISSANCE ORBITER HIRISE IMAGES January 24, 2008 o Southern Dunes and Spiders http://hirise.lpl.arizona.edu/PSP_006538_1035 o Layered Sediments in Terby Crater http://hirise.lpl.arizona.edu/PSP_006475_1525 o Splotches and Channels Near Sisyphi Montes http://hirise.lpl.arizona.edu/PSP_005424_1075 o Polar Pit Gullies http://hirise.lpl.arizona.edu/PSP_005410_1115 All of the HiRISE images are archived here: http://hirise.lpl.arizona.edu/ Information about the Mars Reconnaissance Orbiter is online at http://www.nasa.gov/mro. The mission is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, for the NASA Science Mission Directorate, Washington, D.C. Lockheed Martin Space Systems, of Denver, is the prime contractor and built the spacecraft. HiRISE is operated by the University of Arizona. Ball Aerospace and Technologies Corp., of Boulder, Colo., built the HiRISE instrument. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] test Ignore
test __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Museum of Flight Hosting Mars Meteorite
Museum of Flight hosting Mars rock, NASA display Seattle Times 01/25/2008 Author: Christina Siderius (Copyright 2008) When Jim Hull flew into Seattle-Tacoma International Airport this week,he was toting an unusual item in his carry-on bag: part of a meteorite from Mars. Hull, manager of exhibits and artifacts for NASA, was in charge of making sure the sample made it safely to the Museum of Flight as part of a four-day exhibition there accompanying a NASA forum. The exhibition, which opened Thursday and shows visitors NASA's plans to explore Mars and the moon, features a model of a next-generation rocket, a virtual tour of the international space station and a spacesuit display. The meteorite piece, to be on view for about a month at the Museum of Flight, was found in Antarctica in 1980. Scientists concluded it was from Mars by comparing the rock to data obtained by the Viking Mars Lander. Today, NASA will hold its Future Forum, an invitation-only conference for space-industry professionals. Attendees include representatives from Boeing, Google and the University of Washington. Seattle is the first stop in NASA's forum series. In February it will head to Cincinnati. St. Louis, Miami, Boston, Chicago and the Bay Area are also on the schedule. The idea is to reintroduce NASA to communities and talk about the work it is doing, according to Mike Green, a senior manager for strategic communications at NASA. NASA, which is celebrating its 50th anniversary this year, has strong ties to this region. Boeing is the prime contractor on the international space station, responsible for design, development, construction and integration of the station and assisting NASA in operating the orbital outpost. Museum of Flight President Bonnie Dunbar is a former astronaut who served on five shuttle missions. Dunbar will talk about her experiences in space at 2 p.m. Saturday at the museum. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Asteroid 2007 TU24 to Make Rare Close Flyby of Earth January 29
http://www.jpl.nasa.gov/news/news.cfm?release=2008-012 Asteroid to Make Rare Close Flyby of Earth January 29 Jet Propulsion Laboratory January 24, 2008 Scientists are monitoring the orbit of asteroid 2007 TU24. The asteroid, believed to be between 150 meters (500 feet) and 610 meters (2,000 feet) in size, is expected to fly past Earth on Jan. 29, with its closest distance being about 537,500 kilometers (334,000 miles) at 12:33 a.m. Pacific time (3:33 a.m. Eastern time). It should be observable that night by amateur astronomers with modest-sized telescopes. Asteroid 2007 TU24 was discovered by the NASA-sponsored Catalina Sky Survey on Oct. 11, 2007. Scientists at NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif., have determined that there is no possibility of an impact with Earth in the foreseeable future. This will be the closest approach by a known asteroid of this size or larger until 2027, said Don Yeomans, manager of the Near Earth Object Program Office at JPL. As its closest approach is about one-and-a-half times the distance of Earth to the moon, there is no reason for concern. On the contrary, Mother Nature is providing us an excellent opportunity to perform scientific observations. Asteroid 2007 TU24 will reach an approximate apparent magnitude 10.3 on Jan. 29-30 before quickly becoming fainter as it moves farther from Earth. On that night, the asteroid will be observable in dark and clear skies through amateur telescopes with apertures of at least 7.6 centimeters (3 inches). An object with a magnitude of 10.3 is about 50 times fainter than an object just visible to the naked eye in a clear, dark sky. NASA detects and tracks asteroids and comets passing close to Earth. The Near Earth Object Observation Program, commonly called Spaceguard, discovers, characterizes and computes trajectories for these objects to determine if any could be potentially hazardous to our planet. For more information, visit http://neo.jpl.nasa.gov. DC Agle 818-393-9011 Jet Propulsion Laboratory, Pasadena, Calif. [EMAIL PROTECTED] Grey Hautaluoma 202-358-0668 Headquarters, Washington [EMAIL PROTECTED] 2008-012 __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Stardust Comet Dust Resembles Asteroid Materials
https://publicaffairs.llnl.gov/news/news_releases/2008/NR-08-01-05.html Lawrence Livermore National Laboratory News Release Contact: Anne M. Stark Phone: (925) 422-9799 E-mail: [EMAIL PROTECTED] FOR IMMEDIATE RELEASE January 24, 2008 NR-08-01-05 Stardust comet dust resembles asteroid materials LIVERMORE, Calif. - Contrary to expectations for a small icy body, much of the comet dust returned by the Stardust mission formed very close to the young sun and was altered from the solar system's early materials. When the Stardust mission returned to Earth with samples from the comet Wild 2 in 2006, scientists knew the material would provide new clues about the formation of our solar system, but they didn't know exactly how. New research by scientists at Lawrence Livermore National Laboratory and collaborators reveals that, in addition to containing material that formed very close to the young sun, the dust from Wild 2 also is missing ingredients that would be expected in comet dust. Surprisingly, the Wild 2 comet sample better resembles a meteorite from the asteroid belt rather than an ancient, unaltered comet. Comets are expected to contain large amounts of the most primitive material in the solar system, a treasure trove of stardust from other stars and other ancient materials. But in the case of Wild 2, that simply is not the case. By comparing the Stardust samples to cometary interplanetary dust particles (CP IDPs), the team found that two silicate materials normally found in cometary IDPs, together with other primitive materials including presolar stardust grains from other stars, have not been found in the abundances that might be expected in a Kuiper Belt comet like Wild 2. The high-speed capture of the Stardust particles may be partly responsible; but extra refractory components that formed in the inner solar nebula within a few astronomical units of the sun, indicate that the Stardust material resembles chondritic meteorites from the asteroid belt. The material is a lot less primitive and more altered than materials we have gathered through high altitude capture in our own stratosphere from a variety of comets, said LLNL's Hope Ishii, lead author of the research that appears in the Jan. 25 edition of the journal, Science. As a whole, the samples look more asteroidal than cometary. Because of its tail formed by vaporizing ices, Wild 2 is, by definition, a comet. It's a reminder that we can't make black and white distinctions between asteroids and comets, Ishii said. There is a continuum between them. The surprising findings contradict researchers' initial expectations for a comet that spent most of its life orbiting in the Kuiper Belt, beyond Neptune. In 1974, Wild 2 had a close encounter with Jupiter that placed it into its current orbit much closer to Earth. Comets formed beyond the so-called frost line where water and other volatiles existed as ices. Because of their setting far from the sun, they have been viewed as a virtual freezer, preserving the original preliminary ingredients of the solar system's formation 4.6 billion years ago. The Stardust spacecraft traveled a total of seven years to reach Wild 2 and returned to Earth in January 2006 with a cargo of tiny particles for scientist to analyze. This is one of the first studies to closely compare Stardust particles to CP IDPs. This class of IDPs is believed to contain the most primitive and unaltered fraction of the primordial material from which our planets and other solar system objects formed. They are highly enriched in isotopically anomalous organic and inorganic outer solar nebula materials inherited - through the presolar molecular cloud - from dust produced around other stars. IDPs are gathered in the stratosphere by high altitude airplanes (ER-2s and WB-57s) that are typically more than 50 years old. The Livermore team specifically searched for two silicate materials in Stardust that are believed to be unique to cometary IDPs: amorphous silicates known as GEMS (glass with embedded metal and sulfides); and sliver-like whiskers of the crystalline silicate enstatite (a rock-forming mineral). Surprisingly, the team found only a single enstatite whisker in the Stardust samples, and it had the wrong crystallographic orientation - a form typical of terrestrial and asteroidal enstatite. Objects similar to GEMS were found, but Ishii and the team showed they were actually created during the high speed 6-kilometer per second impact of Wild 2 comet dust with the Stardust spacecraft's collector by making similar material in the laboratory. In analyzing the Stardust material, Ishii's team used Livermore's SuperSTEM (scanning transmission electron microscope). Ishii said future analyses should focus on larger-grained materials, so-called micro-rocks, which suffered less alteration. The material found in primitive objects just wasn't there in the samples, said John Bradley, another LLNL author. I think
[meteorite-list] Weston sizes
Hello everyone, I will be marketing my 4 gram piece of Weston in some newspapers in western Connecticut soon and want to be accurate in my assessment of its size. I have seen very little over a gram available and was wondering how many of you may have pieces over 4 grams? Thanks very much. George __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Mars Odyssey THEMIS Images: January 21-25, 2008
MARS ODYSSEY THEMIS IMAGES January 21-25, 2008 o Aonia Terra Dunes (Released 21 January 2008) http://themis.asu.edu/zoom-20080121a o Copernicus Dunes (Released 22 January 2008) http://themis.asu.edu/zoom-20080122a o Dust Devil Tracks (Released 23 January 2008) http://themis.asu.edu/zoom-20080123a o Gullies (Released 24 January 2008) http://themis.asu.edu/zoom-20080124a o Gullies (Released 25 January 2008) http://themis.asu.edu/zoom-20080125a All of the THEMIS images are archived here: http://themis.asu.edu/latest.html NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in co.oration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] New Horizons: A Hi-Def Peek at Pluto
http://pluto.jhuapl.edu/news_center/news/012408.htm New Horizons: NASA's Pluto-Kuiper Belt Mission January 24, 2008 A Hi-Def Peek at Pluto New Horizons made its first detection of Pluto using the high-resolution mode of its Long Range Reconnaissance Imager (LORRI) during three separate sets of observations in October 2007. LORRI first detected Pluto in September 2006 in its low-resolution format, says New Horizons Principal Investigator Alan Stern, of NASA Headquarters, but this time around we were able to take longer exposures and to detect Pluto using a camera resolution that is four times better than before. New Horizons was still too far from Pluto (3.6 billion kilometers, or 2.2 billion miles) for LORRI to resolve any details on Pluto's surface - that won't happen until summer 2014, approximately one year before closest approach. For now the entire Pluto system remains a bright dot to the spacecraft's telescopic camera, though LORRI is expected to start resolving Charon from Pluto - seeing them as separate objects - in summer 2010. During the October 2007 observations, Pluto was located in the constellation Serpens, in a region of the sky dense with background stars. Using LORRI's high-resolution mode allowed us to more easily pick out Pluto in a virtual sea of surrounding stars, says New Horizons Project Scientist Hal Weaver of the Johns Hopkins University Applied Physics Laboratory (APL), which provided the LORRI instrument. Marking another first for New Horizons, LORRI also detected clear variations in Pluto's brightness. Pluto rotates on its axis once every 6.4 days, allowing observers to see different portions of the planet's surface (i.e., different longitudes). From ground-based and Hubble Space Telescope observations scientists have seen repeatable, well-defined differences in Pluto's brightness they believe is caused by variations in frost cover over its surface. New Horizons will determine whether that is indeed the correct explanation when the spacecraft flies by Pluto in July 2015. In the meantime, it's gratifying to see that New Horizons itself now has the capability to track Pluto's brightness variations over the next seven and a half years, and from a slightly different perspective than what we normally see from Earth, Weaver says. [Image] This image demonstrates the first detection of Pluto using LORRI's high-resolution mode, which provides a clear separation between Pluto and numerous nearby background stars. Typically, LORRI's exposure time in hi-res mode is limited to approximately 0.1 seconds, but by using a special pointing mode that allowed an increase in the exposure time to 0.967 seconds, scientists were able to spot Pluto, which is approximately 15,000 times fainter than human eyes can detect. [Image] This montage shows the effects of using different resolutions and exposure times during LORRI observations of Pluto on October 6, 2007. The top left image was taken with LORRI in high-resolution mode using an exposure time of 0.967 seconds. The image to its right had the same exposure time but was taken in LORRI's low-resolution mode with pixels that are four times larger, which makes the stars and Pluto look fatter and, therefore, less distinct. The image to the lower left is another LORRI image taken in low-resolution mode, but with an exposure time that is four seconds longer, which allows us to see deeper and pick up even fainter stars. (Pluto is clearly detected and is circled in each of these LORRI images.) The lower right image is a digitized photographic plate of the same portion of the sky taken in July 1986 by a large telescope in Australia for the Palomar Sky Survey. Pluto is not in this image, but Pluto's location in the October 2007 observations is indicated by the small red circle. This image captures stars that are approximately 40 times fainter than can be seen in the lower left LORRI image and illustrates the richness of the background star field in this region of the sky. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Enthusiasts of Martian Meteorites
Hello All, Since we all share this passion for meteorites, those messengers from our solar neighborhood, I would like to draw your attention to Bob Verish's offer of one of the most spectacular Martian meteorites in recent history! How many among us can really boast of owning a piece of either LA 001 or LA 002!?! Have a look and watch your saliva ;-) http://marzmeteorite.tripod.com/saw-cuttings/la-saw.htm Bernd __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
